MC LC TRANG CHNG 1 DN NHP ............................................................................................... 9 1.1 T VN ....................................................................................................... 9 1.2 TM QUAN TRNG CA TI .................................................................. 10 1.3 GII HN TI NGHIN CU ................................................................... 10 1.4 MC TIU NGHIN CU ................................................................................ 10 1.5 PHNG PHP NGHIN CU ....................................................................... 11 1.6 K HOCH NGHIN CU ............................................................................... 11 1.7 KT QU NGHIN CU CA TI ........................................................... 12 CHNG 2 S LC H THNG GSM .................................................................14 2.1 CC THNH PHN MNG GSM.................................................................... 14 2.1.1 CU HNH C BN CA H THNG THNG TIN DI NG GSM ...14 2.1.2 CHC NNG CA CC KHI ..................................................................15 2.2 BNG TN S DNG TRONG GSM .............................................................. 19 2.2.1 GSM 900 ........................................................................................................19 2.2.2 GSM 1800 ......................................................................................................20 2.2.3 GSM 1900 ......................................................................................................21 2.3 CC TH TC TRONG GSM ........................................................................... 21 2.3.1 CP NHT V TR ....................................................................................... 21 2.3.2 TH TC TM GI ...................................................................................... 25 2.3.3 TH TC KHI XNG CUC GI ....................................................... 25 2.3.4 TH TC NHN CUC GI .....................................................................26 2.3.5 CHUYN GIAO (HANDOVER)..................................................................27 2.4 M T QU TRNH THIT LP CUC GI TRONG MNG GSM ........... 28 2.4.1 TRM DI DNG MS THC HIN CUC GI ........................................28 2.4.2 MS NHN CUC GI .................................................................................30 CHNG 3 TNG QUAN V TIN NHN SMS ...................................................... 33 3.1 GII THIU V SMS ......................................................................................... 33 3.2 TIN NHN SMS CHUI/ TIN NHN SMS DI ............................................. 33 3.3 IU G LM CHO TIN NHN SMS TR LN RNG KHP .................... 34 3.4 SMS CENTRE/SMSC ......................................................................................... 35

3.5 NHN TIN SMS QUC T ............................................................................... 35 3.6 SMS GATEWAY ................................................................................................ 36 3.7 M NGUN M V PHN MM SMS GATEWAY ..................................... 38 CHNG 4 B GIAO THC TCP/IP ........................................................................39 4.1 GII THIU ........................................................................................................ 39 4.2 TNG QUT V TCP/IP ................................................................................... 39 4.2.1.TNG GIAO DIN MNG (NETWORK INTERFACE LAYER) ............39 4.2.2 TNG LIN MNG (INTERNET LAYER) ...............................................40 4.2.3 TNG GIAO VN (TRANSPORT LAYER) ..............................................40 4.2.4 TNG NG DNG (APPLICATION LAYER) .........................................40 4.3 A CH IP .......................................................................................................... 41 4.4 A CH IP PUBLIC V A CH IP PRIVATE.............................................. 43 4.4.1 A CH IP PUBLIC.....................................................................................43 4.4.2 A CH IP PRIVATE ..................................................................................43 4.5 LP A CH ...................................................................................................... 44 4.6 SUBNET MASK.................................................................................................. 46 4.7 DEFAULT GATEWAY ...................................................................................... 47 4.8 CHIA SUBNET ................................................................................................... 47 4.9 SUPERNETTING ................................................................................................ 49 4.10 CIDR (CLASSLES INTER-DOMAIN ROUTING) NH TUYN LIN VNG KHNG PHN LP .................................................................................... 50 4.11 VARIABLE LENGTH SUNET MASKS (SUBNET MASKS C CHIU DI THAY I) ............................................................................................................... 51 4.12 NGUYN L HOT NG CA GIAO THC TCP/IP V INTERNET ... 55 4.12.1 A CH VT L HAY CN GI L A CH MAC ........................... 59 4.12.2 SAP ..............................................................................................................60 4.12.3 A CH MNG( NETWORK ADDRESS) ..............................................60 4.12.4 PROTOCOL ID ........................................................................................... 62 4.12.5 PORT ...........................................................................................................62 4.12.6 USERNAME ............................................................................................... 62 4.13 CCH M PORT CHO MODEM .................................................................... 66 CHNG 5 THIT K PHN CNG .......................................................................70

5.1 TNG QUAN V H THNG .......................................................................... 70 5.2 S KHI CA GSM MODULE ................................................................. 71 5.3 KHI IU KHIN V GIAO TIP ................................................................ 72 5.3.1 S KHI ................................................................................................ 72 5.3.2 CHIP ARM STM32F103 ...............................................................................72 5.3.3 KHI MAX232 ............................................................................................. 85 5.3.4 KHI NGUN 5V S DNG IC 7805 ....................................................... 86 5.3.5 KHI NGUN 3.3V S DNG IC 1117 ....................................................87 5.4 KHI GSM MODULE SIM300CZ..................................................................... 88 5.4.1 S KHI ................................................................................................ 88 5.4.2 KHI MODULE SIM300CZ ........................................................................88 CHNG 6 KT LUN ............................................................................................118 6.1 SN PHM ....................................................................................................... 118 6.2 KT NI V S DNG H THNG ............................................................. 122 6.2.1 S DNG H THNG IU KHIN THIT B ..............................122 6.2.2 S DNG H THNG NH V I TNG ................................125 TI LIU THAM KHO ...........................................................................................127

LIT K HNH Hnh 1.M hnh h thng GSM .....................................................................................14 Hnh 2.H thng trm gc ............................................................................................. 15 Hnh 3.Chc nng ca MS ............................................................................................ 16 Hnh 4.SIM CARD .....................................................................................................17 Hnh 5.Giao tip gia SSS v cc h thng khc .......................................................... 18 Hnh 6.Bng tn GSM D900 ........................................................................................ 20 Hnh 7.Bng tn h thng DSC 1800 ............................................................................20 Hnh 8.Bng tn GSM 1900 .......................................................................................... 21 Hnh 9.Cp nht v tr kiu bnh thng ........................................................................22 Hnh 10.Qu trnh ri khi mng ..................................................................................23 Hnh 11.ng k nh k .............................................................................................. 24 Hnh 12.Cuc gi t mng c nh kt cui MS (MTC) ...........................................27 Hnh 13.Mt SMS gateway hot ng nh mt relay gia hai SMSC ......................... 36 Hnh 14.Mt ng dng tin nhn SMS dng text kt ni cc SMSC khng cn SMS gateway .......................................................................................................................... 37 Hnh 15.Mt ng dng tin nhn SMS dng text kt ni cc SMSC thng qua mt SMS gateway .......................................................................................................................... 37 Hnh 16.Mt ng dng tin nhn SMS dng text kt ni mt nhm cc in thoi (hay cc modem thng qua SMS gateway) ...........................................................................38 Hnh 17.M t khi qut v B giao thc TCP/IP ........................................................ 41 Hnh 18.Cu trc bit ca mt a ch IP(V4) ................................................................ 42 Hnh 19.Cch i s nh phn sang thp phn .............................................................. 43 Hnh 20.S khc bit gia cc lp IP ............................................................................45 Hnh 21.Minh ha u im ca chia Subnet .................................................................48 Hnh 22.Supernetting .....................................................................................................50 Hnh 23.nh tuyn lin vng khng phn lp ............................................................. 50 Hnh 24.Subnet mask chiu di thay i .......................................................................51 Hnh 25.Kt cu vt l ca mng ..................................................................................56 Hnh 26.ng i ca mng ......................................................................................... 57 Hnh 27.H thng tn v a ch ca mng Internet ...................................................... 59 Hnh 28.a ch IP vt l ............................................................................................... 60 Hnh 29.S DNS .......................................................................................................61 Hnh 30.Gi 13 byte d liu theo chun TCP ............................................................... 64 Hnh 31.D liu thng bo tha nhn ACK ..................................................................64 Hnh 32.Qu trnh kt ni gia 2 my trong mng........................................................ 65 Hnh 33.ng nhp modem ........................................................................................... 66 Hnh 34.Giao din Port NAT......................................................................................... 67 Hnh 35.Thay i thng s Port NAT ...........................................................................67 Hnh 36.B chn Active Firewall ..................................................................................68 Hnh 37.S hot ng tng quan ca h thng ........................................................ 70

Hnh 38.S khi GSM module .................................................................................71 Hnh 39.S khi ca mch iu khin v giao tip ..................................................72 Hnh 40.Chip ARM Cortex M3 .....................................................................................72 Hnh 41.So snh b nh ARM thng v ARM Cortex ...............................................74 Hnh 42.S chn chip STM32F103 ..........................................................................75 Hnh 43.S khi ca thit b ngoi vi USB .............................................................. 76 Hnh 44. di Word lp trnh ...................................................................................... 82 Hnh 45.Cu hnh cc bit Stop ....................................................................................... 83 Hnh 46.Pht hin bit Start ............................................................................................ 84 Hnh 47.S mch nguyn l khi MAX232 ............................................................. 85 Hnh 48.S chn ca IC MAX232 ...........................................................................86 Hnh 49.S mch nguyn l ngun 5V ....................................................................86 Hnh 50.S chn IC 7805 ......................................................................................... 87 Hnh 51.Khi ngun 3.3V s dng IC 1117 .................................................................87 Hnh 52.S khi tng quan ca module GSM ......................................................... 88 Hnh 53.Kch thc k thut ca module SIM300CZ ..................................................91 Hnh 54.V tr chn kt ni DIP ca module SIM300CZ ..............................................91 Hnh 55.Ni chn VBAT cho module Sim300CZ ........................................................ 96 Hnh 56.in p VBAT trong qu trnh truyn............................................................. 96 Hnh 57.Thi gian m SIM300CZ ................................................................................96 Hnh 58.Kt ni giao tip ni tip .................................................................................97 Hnh 59.Giao tip nng cp phn mm v giao tip .....................................................98 Hnh 60.Cu hnh giao tip Speaker ..............................................................................99 Hnh 61.Cu hnh giao tip Speaker vi b khuch i ................................................99 Hnh 62.Cu hnh giao tip Microphone .....................................................................100 Hnh 63.Cu hnh Buzzer ............................................................................................100 Hnh 64.Giao tip th SIM ..........................................................................................101 Hnh 65.Mch kt ni LED bo NETLIGHT ..............................................................101 Hnh 66.Thit lp cu hnh mc nh ..........................................................................102 Hnh 67.Khi to vng nh .........................................................................................105 Hnh 68.Nhn v c tin nhn .....................................................................................106 Hnh 69.Gi tin nhn ...................................................................................................107 Hnh 70.Thc hin cuc gi ........................................................................................109 Hnh 71.Nhn cuc gi n .........................................................................................111 Hnh 72.Khi to vng nh .........................................................................................112 Hnh 73.Thit lp kt ni GPRS ..................................................................................113 Hnh 74.Truyn nhn gi d liu TCP ........................................................................114 Hnh 75.Hy b kt ni ...............................................................................................115 Hnh 76.S mch nguyn l mch ngun ..............................................................116 Hnh 77.IC LM2576 ....................................................................................................117 Hnh 78.Layout Kit ARM............................................................................................118

Hnh 79.Kit iu khin - ARM Kit ..............................................................................119 Hnh 80.Layout Kit GSM Sim300CZ .........................................................................120 Hnh 81.Module Sim300CZ ........................................................................................121 Hnh 82.Giao din iu khin ca phn mm SMSCK ...............................................122 Hnh 83.Giao tip iu khin ngoi vi qua cng USB ................................................122 Hnh 84.M hnh iu khin qua Socket .....................................................................123 Hnh 85.M hnh iu khin qua tin nhn SMS ..........................................................123 Hnh 86.M hnh h thng y ...............................................................................124 Hnh 87.M hnh h thng nh v i tng ..............................................................125

LIT K BNG Bng 1.K hoch thc hin ti ..................................................................................11 Bng 2.M t s kt hp gia k hiu thp phn v k hiu khoa hc .......................... 42 Bng 3.Cc vng IP cung cp cho host .........................................................................44 Bng 4.M t khi qut v cc lp a ch IP ................................................................ 45 Bng 5.Nhng Subnet Mask mc nh cho cc Lp mng ...........................................46 Bng 6.Chia Subnet Mask ............................................................................................. 53 Bng 7.Chia Subnet Mask ............................................................................................. 54 Bng 8.Chia Subnet Mask ............................................................................................. 54 Bng 9.Chia Subnet Mask cho cc lp ..........................................................................55 Bng 10.Tnh nng ch cht SIM300CZ ......................................................................89 Bng 11.Chc nng chn ca module SIM300CZ ........................................................ 92 Bng 12.M t chn kt ni DIP ...................................................................................93 Bng 13.Trng thi bo hiu n .................................................................................101

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CHNG 1 DN NHP1.1 T VN Ngy nay, vi s pht trin nh v bo ca khoa hc cng ngh, c bit l s bng n trong lnh vc Cng ngh thng tin v Vin thng to ra bc ngoc quan trng p ng nhu cu ca con ngi, bin nhng i hi tng chng nh khng tng trc y thnh hin thc. Vi nhu cu thng tin ngy cng tng ca con ngi, mng vin thng ra i p ng nhu cu . Hin nay, mng vin thng tr nn ph bin trn ton cu v gn gi vi con ngi, khng ch p ng nhu cu trao i thng tin n thun (nghe gi, nhn tin) m chng cng ngy cng c ng dng rng ri vo nhiu lnh vc. Vi s pht trin nhanh chng cc dch v v ng dng vic thng tin qua mng vin thng ngy tin li, tit kim thi gian, m bo an ton v tit kim c chi ph s dng. Vi cht lng mng vin thng nh hin nay to iu kin cho cc ng dng v iu khin t xa ra i v cng ngy cng c ng dng rng ri. X hi loi ngi pht trin i hi con ngi phi hot ng trong cc mi trng phc tp v nguy him hn, khi iu khin t xa tr nn mt yu cu tt yu. T nhng robot lm vic trong cc hm m, nh my in ht nhn, di y i dng, robot chin trng hay cc robot khm ph cc hnh tinh xa xi u l cc thnh tu cng ngh v iu khin t xa. Vi s pht trin ca mng Internet v cng ngh robot, ngnh y khoa thc hin c mt vic khng tng l phu thut tim t xa qua mng Internet. Bc s chuyn gia tim mch ngi M Andre Ng thc hin thnh cng ca phu thut tim t xa u tin ca th gii ti Bnh vin Glenfield Leicester thuc Vng quc Anh. Bng cch s dng thao tc trn b iu khin Remote Catheter c ch to bi cng ty Catheter Robotics New Jersey, United States. Vi iu kin c s vt cht hin c nc ta v nhu cu thc t. Th ng dng iu khin cc thit b t xa qua mng Internet v mng in thoi di ng GSM l rt kh thi. ng dng ny s gip ngi iu khin cc th qun l v iu khin cc thit b mt cch nhanh chng, chnh xc, hiu qu m khng b gii hn v khong cch ch cn ni c mng Internet hoc mng di ng ph sng. Xut pht t thc tin , nhm thc hin ti quyt nh nghin cu v thc hin ti THIT K H THNG GIM ST V IU KHIN T XA QUA MNG INTERNET V GSM Vi ti trn nhm ti thc hin vic iu khin t xa theo ba hng hng chnh: iu khin trc tip qua cp USB kt ni gia my tnh c ci phn mm ng dng SMS Controller Kit v KIT iu khin. Cho php iu khin thit b qua phn mm vi khon cch ngn.

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iu khin Kit iu khin thng qua Socket mng Internet/LAN gia cc my tnh c ci phn mm SMS Controller Kit. iu khin thit b qua tin nhn SMS t bt k thu bao di ng no. KIT iu khin s nhn tin nhn SMS theo cu trc cho trc. Phn tch yu cu iu khin v thc hin iu khin thit b. Ngoi ra h thng cn c cc chc nng ph ging nh mt chic di ng nh nhn v thc hin cuc gi v nhn tin. 1.2 TM QUAN TRNG CA TI Hin nay, t nc ta ang tin hnh cng nghip ha hin i ha t nc. ng trc bi cnh bng n khoa hc cng ngh hin nay. Vit Nam thc hin ch trng i tc n u v khoa hc cng ngh, to tin cho cc lnh vc khc pht trin. V Vit Nam ang tr thnh ni y tim nng v pht trin khoa hc cng ngh v in t. c bit l ni pht trin nhanh chng trong cc lnh vc Cng ngh thng tin, in t vin thng v t ng ha. Trong lnh vc in t th ng dng iu khin t xa kh ph bin, chng hn nh: iu khin bng tia hng ngoi, sng v tuyn, sng siu m ... tuy nhin nhng phng php ny hn ch v iu kin mi trng, a hnh v phm vi iu khin hp. Do , ti ny khng nhng l mt yu cu t thc t khch quan m c vai tr c bit quan trng trong hin ti v tng lai. u im rt d nhn thy ca ti l khc phc cc hn ch v khong cch, rt thng dng d dng thc hin vi cc thit b gn gi vi con ngi, s gp phn tng hiu sut thit b, gim tn hao v thi gian v chi ph. t bit l n rt ph hp vi phong cch lm vic ngy cng hin i v nng ng trong thi k khoa hc cng ngh hin nay. V vy, vic thc hin ti l mt nhu cu ht sc cn thit v cng l l do nhm thc hin quyt nh chn ti ny. 1.3 GII HN TI NGHIN CU Do iu kin thi gian v kinh ph c hn, kinh nghim v kin thc cn hn ch nn phm vi ti ca nhm thc hin gm cc ni dung nh sau: - S dng module SIM300CZ thit lp giao tip vi mng di ng GSM v GPRS. - Dng chip ARM STM32F103x lm chip iu khin thit b v giao tip vi phn mm qun l . - S dng Socket mng v tin nhn phc v cho vic iu khin t xa. 1.4 MC TIU NGHIN CU - n c nghin cu v thc hin vi mc ch p dng nhng kin thc c hc trong nh trng thit k, to ra mt h thng iu khin t ng t xa bng tin nhn SMS v qua mng Internet hon chnh.

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- Tm hiu v h thng in thoi di ng GSM hin nay. Nghin cu v s dng cc module GSM/GPRS ph bin hin nay (V d nh cc module SIMxxx). Module nhm thc hin nghin cu v s dng l module SIM300CZ ca hng SIMCom. - Nghin cu v s dng chip vi iu khin ARM Cortex M3. Chip m nhm tin hnh nghin cu v s dng l chip STM32F103 ca hng STMicroelectronics. - Nghin cu v lp trnh socket trn Java. Sn phm ca nhm l phn mm giao tip iu khin SMS Controller Kit. C kh nng giao tip vi KIT iu khin qua cng USB v giao tip Socket vi my tnh khc qua mng Internet vi chun giao tip TCP/IP. - Nghin cu lp trnh Driver cho h thng. M c th y l lp trnh driver cho cng USB. 1.5 PHNG PHP NGHIN CU Phng php c v nghin cu ti liu: Ch yu l cc ti liu c kin thc lin h n k thut in t, ngoi vi v vi x l, cc phng thc giao tip. Phn tch cng trnh lin quan. Phng php thc nghim: Kt ni phn cng (board) giao tip USB, Cng COM, socket. Dng module kho st o t v tr sau gi v server qua kt ni Internet v GPRS 1.6 K HOCH NGHIN CU Bng 1: K hoch thc hin ti

Thi gian STT Ni dung Tun 1,2 Tun 3,4 Tun 5,6 Tun 7,8 Tun 9,10 Tun 11,12

1 2 3

Xc nh ti Thu thp ti liu c phn tch ti liu Thit k v thi cng phn cng Thit k phn mm

X X X X X X X X

4 5

X

X

X X

X X X

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6

Vit cng v in n

X

1.7 KT QU NGHIN CU CA TI Vi nhng mc tiu v k hoch ra, cng vi s n lc nghin cu, tm ti ca cc thnh vin trong nhm thc hin ti, nhm thc hin t c nhng kt qu nht nh sau: Thit k thnh cng kit giao tip module sim300CZ vi cc tnh nng: + Nhn v gi in thoi thng qua phn mm iu khin SMS Controller Kit giao tip vi kit iu khin. + Nhn v gi tin nhn thng qua phn mm iu khin SMS Controller Kit giao tip vi kit iu khin. Thit k thnh cng kit iu khin giao tip s dng chip ARM Cortex M3 vi cc tnh nng sau: + Giao tip vi phn mm iu khin qua cng USB gi nhn v x l cc yu cu t phn mm iu khin SMS Controller Kit nh : iu khin bt tt thit b, gi in, nhn cuc gi, nhn tin nhn v gi tin nhn. + Giao tip thnh cng vi kit SIM300CZ nhn cuc gi, gi in, nhn tin nhn v gi tin nhn + C kh nng nhn cuc gi c lp m khng cn kt ni n my tnh v phn mm iu khin + C kh nng iu khin thit b thng qua tin nhn mt cch c lp m khng cn kt ni n my tnh v phn mm iu khin Thit k thnh cng phn mm iu khin SMS Controller Kit vi cc tnh nng: + L mt phn mm ci t hon chnh c th hot ng trn cc phin bn Windows XP,Windows Vista v Windows 7. + Giao tip vi kit iu khin gi cc yu cu iu khin thit b. + C th gi in, nhn tin, nhn cuc gi v nhn tin nhn thng qua kt ni vi ngoi vi l kit iu khin v kit SIM300CZ. + Gi nhn cc yu cu iu khin bt tt thit b trn socket mng cng nh thng qua tin nhn SMS. + C kh nng nh v, gim st ton cu cc i tng v hin th ln bn Google Earth cng nh bn c nhn. Mt h thng qun l xe bus hon chnh c chn minh ha cho kh nng ca phn mm. + Cho php kim tra thng tin ti khon cng nh kim sot thng tin mng di ng ca kit iu khin. Ngoi ra, kit iu khin c thit k sn sng cho vic pht trin cc ng dng di ng cc ti lin quan n lp trnh di ng trong tng lai.

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CHNG 2 S LC H THNG GSM2.1 CC THNH PHN MNG GSM 2.1.1 CU HNH C BN CA H THNG THNG TIN DI NG GSMSS

ISDN

AUC

PSPDN

VLR

HLR

EIR

H thng chuyn mch

PSTN

MSC

OMS

PLMN BSS BSC BTS H thng trm gc Truyn dn tin tc Kt ni cuc gi v truyn dn tin tc

MS

Hnh 1.M hnh h thng GSM Cc k hiu: SS (Switching Subsystem ): H thng chuyn mch AUC (Authentication Center ): Trung tm nhn thc VLR (Visitor Location Register ): Thanh ghi nh v tm tr HLR (Home Location Register ): Thanh ghi nh v thng tr EIR (Equipment Indentity Register ): Thanh ghi nhn dng thit b MSC (Mobile services Switching Center) Trung tm chuyn mch cc dch v di ng gi tt l: Tng i v tuyn BSS ( Base Station System ): H thng con trm gc BTS ( Base Transceiver Station ): Trm thu pht gc BSC (Base Station Controller ): B iu khin trm gcCHNG 2

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MS ( Mobile Station ): Trm di ng OMC ( Operation and Maintenance Center ): Trung tm khai thc v bo dng ISDN ( Integrated Services Digital Network): Mng s lin kt a dch v PSPISDN ( Packet Switch Public Data Network ): Mng s liu cng cng chuyn mch gi CSPDN ( Circuit Switch Public Data Network ): Mng s liu cng cng chuyn mch mch PSTN ( Public Switched Telephone Network ): Mng in thoi chuyn mch cng cng PLMN ( Public Land Mobile Network ): Mng di ng cng cng mt t 2.1.2 CHC NNG CA CC KHI Cu trc tng qut ca h thng GSM c th chia lm 3 h thng con: - H thng con trm gc BSS - H thng con chuyn mch SS - H thng con khai thc v bo dng OMS 2.1.2.1 H thng con BSS Chc nng ca BSS l to ra vng hot ng cho thu bao di ng v thc hin truyn dn thng sut tn hiu.

Hnh 2.H thng trm gc

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BSS gm c 4 thnh phn nh sau: MS: Trm di ng l thit b thu pht c nhn do ngi ng k thu bao trc tip s dng. MS c th l mt may in thoi di ng cm tay, my in thoi di ng xch tay hoc gn trn xe hi. i vi h thng GSM, mt MS gm 2 thnh phn ME v SIM. ME: L thit b phn cng thc hin chc nng thu pht tn hiu. ME tr thnh MS ch khi no SIM card c chn vo trong ME. Nu khng c SIM, ME khng th thc hin c bt c dch v no tr trng hp gi khn cp 112. Mi ME c nhn dng ring bang s nh ngha thit b duy nht (S IMEI) c lu tr bn trong. Mt ME c chia lm 3 khi chc nng: - Thit b u cui TE (Terminal Equipment): cung cp cho thu bao 1 dch v c th (v d my fax). TE khng thc hin bt c chc nng no ca h thng GSM. - MT (Mobile Termination): l thit b chu trch nhim v vic truyn dn thng tin qua giao din v tuyn. - Thit b thch ng TA (Terminal Adaptor): l thit b c s dng to ra s tng hp gia TE v MT.

Hnh 3.Chc nng ca MS SIM : L th chip m bn trong c cc b nh lu tr thng tin c nhn ca thu bao di ng v mt s thng tin ca mng.

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Hnh 4.SIM CARD SIM-card c mt vng nh c nh lu tr cc thng tin ca 1 thu bao c th no , bao gm: - IMSI (International Mobile Subscriber Identity): y l ch s phn bit cc thu bao khc nhau trong mng GSM. IMSI c ti a 15 ch s: - MCC (Mobile Country Code): c 3 ch s, xc nh quc gia m thu bao ng k. - MNC (Mobile Network Code): c 2 ch s, xc nh mng di ng m thu bao ng k. - MSIN (Mobile Subscriber Identification Number): mi gi tr MSIN s xc nh mt thu bao trong mng di ng. T s IMSI ta c th xc nh c mng thng tr (home network) ca thu bao. Kha nhn thc thu bao Ki. Thut ton bo mt A8. Ngoi cc thng tin trn bt buc phi c, trong mi SIM-card cn c mt s thng tin ty chn nh cc mu tin nhn, danh sch cc s in thoi vit tt (gm cc k t hay k hiu i din cho mt s in thoi no ), nhng s in thoi m thu bao va mi gi SIM-card c bo v bng 1 password, gi l m PIN (Personal Identity Number) gm t 4 n 8 ch s, do thu bao ty chn. Nu nhp sai gi tr ca PIN trong 3 ln lin tip (cho d gia cc ln SIM c rt ra hoc tt my) th SIM s b kha. m kha ngi s dng phi nhp vo 1 m s khc b kha, l PUK (PIN Unblocking Key) gm 8 ch s. Trong trng hp sau 10 ln m vn khng nhp c gi tr ng ca PUK th SIM b kha hon ton. Khi thu bao mun s dng thit b di ng thc hin mt dch v no th phi gn SIM-card vo. Nu khng c SIM, MS s khng hot ng c (ngoi tr cc cuc gi khn cp). Mt SIM-card c th c s dng cho nhiu loi ME khc nhau, do rt thun tin cho ngi s dng. Chng hn khi my in thoi ca thu bao b hng, h c th mn my ca ngi khc v gn SIM ca mnh vo dng tm trong thi gian sa cha. Nh vy c th ni SIM-card chnh l nn tng ca h thng lin lc c nhn. BTS: Trm thu pht gc, chc nng ca BTS l to ra vng hot ng cho MS. Vng ph sng nh nht ca mt BTS gi l mt t bo ( cell ). BTS giao tip vi MS qua ng v tuyn. BTS hot ng di s iu khin ca BSC.CHNG 2

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BSC: B iu khin trm gc, chc nng chnh ca BSC l iu khin cc hot ng ca BTS nh: qun l ti nguyn v tuyn, iu khin nhy tn, iu khin chuyn giao Mt BSC c th iu khin nhiu BTS. Vi chc nng ngy, mt BSC c th c xem nh l mt b chuyn mch-bo hiu. TRAU ( Transcoding and Rate Adaption Unit ): B tng thch tc v chuyn m. Nhim v ca TRAU l bin i tc ca lung d liu cho ph hp vi ng truyn ng thi cn thc hin chc nng chuyn m. Tu theo cu hnh tng mng khc nhau m TRAU c th lp t BSC hoc MSC. 2.1.2.2 H thng con chuyn mch SS Chc nng chnh ca SS l x l cuc gi v qun l thu bao di ng.

Hnh 5.Giao tip gia SSS v cc h thng khc Cc thnh phn trong SS gm 5 thnh phn: MSC: Trung tm chuyn mch cc dch v di ng l thnh phn trung tm ca SS, MSC thc hin tm ng v kt ni cuc gi, giao tip vi mng bn ngoi PSTN, ISDN, PLMN khc y l ni duy nht thc hin chc nng chuyn mch cuc gi trong h thng. Ngoi ra MSC cn tng hp s liu ca cc cuc gi tham gia qun l cc ph thu bao. HLR: Thanh ghi nh v thng tr n lu tr tt c cc thng tin ca thu bao di ng, thng tin lu tr trong HLR do ngi khai thc mng cp nht vo. Thng tin ngy khng cho bit v tr hin ti c th ca thu bao di ng m ch cho bit VLR m thu bao ang hin din. Cc trng thng tin lu tr trong HLR gm: CHNG 2

IMSI : S nh ngha thu bao di ng quc t. Ki : Kho nhn thc thu bao. VLR : Hin ti ca thu bao. Cc dch v ca thu bao di ng. MSRN : S chuyn vng ca thu bao di ng

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VLR: Thanh ghi nh v tm tr l c s d liu cha thng tin ca MS. Thng tin ny cho bit v tr hin ti ca MS, trng thi ca MS Thng tin cp nht trong VLR mt cch t ng thng qua th tc cp nhp v tr ca thu bao. Thng tin trong VLR c tnh cch tm thi, n thay i kh thng xuyn. Ngoi ra VLR tham gia vic kim tra nhn thc mt thu bao c quyn truy xut vo mng hay khng. Cc trng thng tin lu tr trong VLR gm: Trng thi ca thu bao ( tt, m, bn, ri). S LAI hin ti ca thu bao. S thu bao tm thi ( TMSI ). MSRN : S chuyn vng ca thu bao di ng EIR: Thanh ghi nhn dng thit b dng qun l thit b di ng ME. Thng tin lu tr trong EIR chnh l cc s nh ngha thit b di ng. EIR c ni n MSC qua ng bo hiu, n cho php MSC kim tra s hp l ca thit b. Bang cch ngy mt MS c th c hoc khng c cho php truy xut vo mng AC: Trung tm nhn thc, chc nng ca AC l kt hp vi HLR cung cp cho VLR cc thng s nhn thc mt MS c quyn truy nhp vo mng hay thng 2.1.2.3 H thng con OMS OMS: Thc cht l mt mng my tnh c kt ni vi cc thnh phn trong h thng thc hin chc nng iu hnh v bo dng h thng. y cng l ni duy nht m ngi khai thc giao tip c vi mng di ng. Mt OMS gm c 2 thnh phn nh sau: OMC: Trung tm iu hnh v bo dng mng. OMC thc hin cc chc nng c tnh cch cc b. Trung tm ngy h tr mt s chc nng sau: Qun l cu hnh ca mng. Qun l qu trnh lm vic ca mng. Qun l bo mt NMC: Trung tm qun l mng, n gim st cc OMC trong mng. Chc nng gim st gm: Gim st cc s c v cnh bo. X l mt s s c trong mng 2.2 BNG TN S DNG TRONG GSM 2.2.1 GSM 900 GSM 900 lm vic trong khong tn 890 MHz 960 MHz c phn b nh sau:

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25 MHz Hng ln Hng xung

890 MHz

915 MHz

935 MHz

960 MHz

Hnh 6.Bng tn GSM D900 Bng tn hng ln ( MS pht, BTS thu )nm trong khong tn s : 890 MHz 915 MHz ( rng l 25 MHz ) Bng tn hng xung ( MS pht, BTS thu ) nm trong khong tn s : 935 MHz 960 MHz Trong D900 c chia lm 124 knh tn s ( RFC ). Mi knh c hai tn s: Mt cho hng ln v mt cho hng xung, khong cch gia hai tn s hng ln v hng xung trong cng mt knh l 45 MHz. rng bng mi knh l 200 KHz Cc mng di ng GSM Vit Nam hin nay ang s dng bng tn ny 2.2.2 GSM 1800 DSC1800 lm vic trong khong tn 1710 MHz 1880 MHz, phn b nh sau:90 MHz

Hng ln

Hng xung

1710 MHz

1785 MHz

1805 MHz

1880 MHz

Hnh 7.Bng tn h thng DSC 1800 Bng tn hng ln ( MS pht, BTS thu ) nm trong khong tn s: 1710 MHz 1785 MHz ( rng l 75 MHz ) Bng tn hng xung ( MS pht, BTS thu ) nm trong khong tn s: 1805 MHz 1880 MHz Trong DSC1800 c chia lm 374 knh tn s ( RFC ). Mi knh c hai tn s: Mt cho hng ln v mt cho hng xung, khong cch gia hai tn s hng ln v hng xung trong cng mt knh l 95 MHz. rng bng mi knh l 200 KHz,

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2.2.3 GSM 1900 DSC1900 lm vic trong khong tn 1850MHz 1990 MHz, phn b nh sau:

60 MHz

Hng ln

Hng xung

1850 MHz

1910 MHz

1930 MHz

1990 MHz

Hnh 8.Bng tn GSM 1900 Bng tn hng ln ( MS pht, BTS thu ) nm trong khong tn s: 1850MHz 1910 MHz ( rng l 60 MHz ) Bng tn hng xung ( MS pht, BTS thu ) nm trong khong tn s: 1930 MHz 1990 MHz Trong D1900 c chia lm 299 knh tn s ( RFC ). Mi knh c hai tn s: Mt cho hng ln v mt cho hng xung, khong cch gia hai tn s hng ln v hng xung trong cng mt knh l 80 MHz. rng bng mi knh l 200 KHz.

2.3 CC TH TC TRONG GSM 2.3.1 CP NHT V TR Cp nht v tr l mt th tc m MS bo cho h thng bit c trng thi v v tr hin ti ca n. Mc ch ca th tc ny l gip cho h thng d dng trong vic qun l thu bao di ng v thc hin tm kim thu bao nhanh hn khi thu bao b gi. Th tc ny c thc hin mt cch t ng khi xy ra mt trong cc iu kin sau y : MS thay i trng thi. MS di chuyn t vng LAI ny sang vng LAI khc. Theo chu k thi gian.

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Hnh 9.Cp nht v tr kiu bnh thng K hiu : ( 1 ): Thng tin h thng. ( 2 ): Thit lp kt ni RR: (2a)=yu cu knh bo hiu; (2b)= n nh knh bo hiu (SDCCH). ( 3 ): Yu cu dch v. ( 4 ): Nhn thc: (4a)= Nu VLR khng c thng bo nhn thc. MSC ly thng s ny t HLR. (4b)= Thng s nhn thc c gi n MS, sau MS tr li nhn thc cho MSC. 2.3.1.1 Cp nht v tr khi MS chuyn trng thi : Khi MS chuyn t trng thi tt my sang m may th cng vic u tin l phi thc hin ng k v tr. y l ln u n thc hin ng k nhp mng. Nguyn tc ca th tc ng k ln u nh sau: Trc ht trm MS qut tt c cc knh tn s trong h thng tm c tn s ng ( FCCH ). Sau MS s c c cc thng tin v mng v thng tin ca BTS m n ang nh v thng qua knh BCCH. Tip theo MS yu cu cho php cp nht v tr thng bo cho VLR ph trch v HLR v v tr ca mnh. Khi MS s s dng mt s thng tin c nhn c lu tr trong SIM v cc thng tin t knh BCCH tr li cho h thng. Cc c s d liu ny s ghi LAI hin thi ca MS. Khi th tc cp nht thnh cng th MSC/ HLR cng nhn l MS tch cc v nh du c thm nhp v tr tch cc vo trng d liu ca mnh. Khi tt ngun MS hay ly SIM card ra khi MS th s xy ra qu trnh trao i bo hiu trong. Trng hp ny c thc hin nh sau:CHNG 2

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MS yu cu mt knh bo hiu pht i bn tin thng bo cho mng rng MS chun b vo trng thi khng tch cc. iu ny c ngha rng mng khng th qun l c MS na. Thng tin chuyn trng thi c th c lu gi ti VLR. Tu chn c ri mng c th cng c thit lp HLR v cng nhn c gi tr li VLR.

Hnh 10.Qu trnh ri khi mng Khi trm MS c bt li ngun ti vng nh v khi n vo trng thi khng tch cc th gi l ti nhp mng. Thng tin pht qung b ca s ni cho MS cn nhp li IMSI hay thng. Qu trnh nhp IMSI trong trng hp ny xy ra nh sau: MS yu cu mt knh bo hiu MSC nhn c nhp li mng t MS MSC gi bn tin nhp li IMSI n VLR VLR xo c ri b IMSI v gi bn tin cng nhn nhp li IMSI n MSC v tr li qu trnh x l cuc gi nh thng l cho MS. MS chp nhn bn tin ni trn. Nu sau khi tt (ri b IMSI) trm MS thay i vng nh v, th khi bt li ngun n phi tin hnh qu trnh cp nht v tr bnh thng vo li trng thi tch cc. Bo hiu cho trng hp cp nht v tr khi nhp li IMSI cng ging nh cp nht v tr bnh thng ch khc 3 bit yu cu cp nht v tr ch ra kiu cp nht v khng cn. 2.3.1.2 Cp nht v tr khi MS thay i LAI Do tnh nng ca thu bao di ng l thay i v tr thng xuyn nn mi khi MS chuyn t LAI ny sang LAI khc th th tc cp nht v tr cng xy ra. Tn ti hai dng cp nht v tr khi thay i LAI:

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MS chuyn t LAI ny sang LAI khc nhng c hai LAI ny u trc thuc cng mt tng i MSC. Trong trng hp ny cp nht v tr khng cn thng bo n HLR v HLR ch qun l v tr ca MS n tng i MSC ph trch MS. MS chuyn t LAI ny sang LAI khc nhng mi LAI ny trc thuc mt tng i MSC khc nhau. V th cp nht v tr c thng bo HLR n ghi li v tr mi ca tng i qun l MSC. MS nhn bit c vic thay i LAI ca mnh nh vo thng tin c c trn knh BCCH. Knh ny c cc BTS pht thng trc cung cp cho cc MS ang nh v ti vng ph sng ca n. Khi MS nhn c thng tin v LAI mi knh BCCH th n s yu cu dch v cp nht v tr. 2.3.1.3 Cp nht v tr nh k trnh vic tm gi khng cn thit khi MSC khng nhn c bn tin ri b IMSI MS khng tch cc, tn ti cp nht mt dng v tr khc c gi l ng k nh k. Qu trnh ny c cho hnh sau:

Hnh 11.ng k nh k Thng tin h thng c pht qung b (1) s thng bo cho MS v ng k nh k c c s dng hay thng . Nu c mng s thng bo cho MS chu k cn thng bo cho mng rng n ang nhp mng. Thng s ny c thit lp bi nh khai thc (0 n 255 ca 6 pht). Nu thng s ny c t bng 1 (6 pht) th MS phi ng k vi chu k 6 pht. Th tc ny c iu khin bi c b nh thi MS (2a) v MSC (2b), MSC c chc nng theo di thi gian ny. Khi ht thi gian ni trn MS phi thc hin cp nht v tr (3a). Cc b nh thi MS v MSC c khi ng li. Nu MS khng ng k trong khong thi gian ni trn b phn theo di ca MSC s nh du MS ny vo trng thi ri mng (3b).

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2.3.2 TH TC TM GI Khi c mt cuc gi ti cho thu bao di ng MS, u tin s thu bao b gi s c gi ti MSC/VLR. Trc khi thc hin chuyn mch, MSC s truy xut vo VLR xc nh v tr hin ti ca thu bao b gi v sau gi bn tin tm gi n cc BTS thng qua BSC. Cc bn tin ny s c thng bo n tt c cc BTS thuc cng mt LAI. Tt c cc MS ang trong LAI ny s nhn c thng bo tm gi nhng ch c MS b gi mi phc p thng bo ny. u tin MS s pht mt bn tin yu cu cp pht knh tip nhn cuc gi n. Trc khi ch nh cho MS mt knh vt l c th th h thng thc hin kim tra qu trnh nhn thc ca thu bao, ng thi bt buc gia BTS v MS phi tho thun mt mt m bo mt thng tin. Khi cc yu cu ca h thng c p ng sn sng th lc ny thu bao mi c quyn tip nhn cuc gi ti. 2.3.3 TH TC KHI XNG CUC GI Khi trm MS trng thi tch cc v ng k v tr, MS c th thc hin cuc gi. Qu trnh thc hin cuc gi c m t nh sau: u tin MS gi yu cu xin cp pht knh n BTS thng qua knh truy xut ngu nhin. MS thng bo rng n mun thit lp cuc gi. S nhn dng trm di ng c phn tch v MS c nh du bn VLR. Trc khi cp knh h thng yu cu thc hin cc cng vic sau: Nhn thc thu bao. Tho thun mt kho mt m trn ng truyn v tuyn. MSC nhn c bn tin thit lp t MS c cha thng tin v loi dch v m MS yu cu, s thoi b gi. MSC kim tra l MS khng c cc dch v cm gi ra (dch v ny c th kch hot hoc bi thu bao hoc bi nh khai thc). Nu khng b cm gi ra qu trnh thit lp cuc gi c tin hnh. Gia MSC v BSC ng truyn c thit lp v knh lu lng c chim. MSC gi yu cu n BSC n nh mt knh lu lng cho ng v tuyn. BSC kim tra nu c knh lu lng ri n n nh knh ny cho cuc gi v yu cu BTS kch hot knh ny. BTS gi tr li cng nhn khi vic kch hot knh lu lng hon thnh. BSC thng bo cho MSC v s hon thnh ny. H thng con iu khin lu lng s phn tch cc ch s ca s thoi B v thit lp kt ni n thu bao b gi. Cuc gi c ni thng qua chuyn mch nhm. Bo chung s c gi n trm MS cho thy rng pha b gi ang chung. Tng chung c to ra tng i pha thu bao B v c gi qua chuyn mch nhm n MS. Nh vy tng chung c gi qua ng v tuyn ch khng to ra MS. Khi thu bao B tr li mng gi bn tin kt ni n MS thng bo rng cuc thoi c chp nhn. MS tr li bng cng nhn kt ni, nh vy thit lp cuc gi hon tt.CHNG 2

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Qu trnh thit lp cuc gi khi xng t trm di ng c trnh by trn l cho cuc gi MOC khng c OACSU (Without off Air Call set up: thit lp sm). Thit lp sm c ngha l mng cp pht knh lu lng cho MS trc khi n khi u thit lp cuc gi mng c nh. Cng c th c tu chn vi OACSU giai on sau ca GSM. Lc ny mng s quyt nh khi no th cp pht knh lu lng. Cp pht c thc hin thi im bt k sau khi khi u thit lp cuc gi mng c nh. Cc im nht l mng c th cp knh lu lng sau khi thu bao B tr li cuc gi. Bn tin bo chung s c gi n MS khi chung pha b gi. S khc nhau y so vi trng hp thit lp sm (Without OACSU) l tng bo hiu chung c to ra ngay MS v knh lu lng vn cha c cp pht. Khi thu bao tr li, mng khi xng th tc n nh cp pht knh lu lng. 2.3.4 TH TC NHN CUC GI MTC phc tp hn MOC v pha gi khng bit hin thi MS ang u. Qu trnh bo hiu cho cuc gi ny c cho hnh v sau: Pha ch gi quay s thu bao di ng b gi: s mng dch v, s lin kt ca thu bao di ng ( MS ISDN) (1). Nu cuc gi khi u t mng c nh PSTN th tng i sau khi phn tch s thoi s bit rng y l cuc gi cho mt thu bao GSM. Cuc gi c nh tuyn n tng i GMSC gn nht (2), y l mt tng i c kh nng hi v nh li tuyn. Bng phn tch MSISDN tng i GMSC tm ra HLR ni MS ng k. GMSC hi HLR (3) thng tin c th quyt nh tuyn n MSC/ VLR ang qun l MS. Bng MSISDN tm ra IMSI v bn ghi ca thu bao. IMSI l s thu bao ch s dng trong mng bo hiu, a ch ca VLR ni MS ang ng k tm thi c lu gi cng vi IMSI trong VLR. HLR giao tip vi VLR nhn c s lu ng thu bao (MSRN: Mobile Subscriber Roaming Number) (4), y l mt s thoi thng thng thuc tng i MSC. VLR gi MSRN n HLR, sau HLR chuyn s ny n GMSC (5). Bng MSRN GMSC c th nh tuyn li cuc gi n MSC tng ng (6), GMSC gi bn tin nhn c t PSTN n MSC.

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Tng i ni ht

Hnh 12.Cuc gi t mng c nh kt cui MS (MTC) gim ti thiu gi thnh, c th s dng PSTN nh tuyn li cuc gi, cc nc c mng PSTN t hoc hot ng khng tt th tt nht l xy dng mt mng kt ni ring gia cc MSC v GMSC. MSC bit c v tr ca MS v n gi bn tin tm gi n tt c cc BSC ang qun l vng nh v ny (7). mng GSM tn ti hai kh nng hoc thng tin v cc trc thuc mt vng nh v c lu gi MSC, hoc thng tin ny c lu gi BSC. mng CME 20 chng hn thng tin ny c lu gi BSC. MSC gi LAI (nhn dng vng nh v) xung cc BSC v BSC phn pht bn tin tm gi n cc BTS(8). tm gi MS, IMSI c s dng (9). C th s dng s nht dng tm thi TMSI m bo b mt. Ngay sau khi nhn c bn tin tm gi MS gi yu cu knh bo hiu. MSC c th thc hin nhn thc v khi u mt m ho nh xt phn trn. MSC c th gi n MS thng tin v cc dch v c yu cu: ting, s liu, fax By gi BSC s lnh cho BTS kch hot knh TCH v gii phng knh bo hiu, bo chung c gi i t MS cho thy rng tng chung c to ra MS. Tng chung cho thu bao ch gi c to ra MSC. Khi thu bao di ng nhc my MS gi bn tin kt ni. Mng hon thnh ng ni thng v gi bn tin cng nhn kt ni n MS. 2.3.5 CHUYN GIAO (HANDOVER) Chuyn giao l qu trnh chuyn i BTS phc v ca MS khi MS ny ang trong ch m thoi. Khi chuyn giao MS c chuyn t mt knh TCH ny sang mt knh TCH khc.CHNG 2

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Cc loi chuyn giao: Chuyn giao gia cc thuc cng mt BSC: Chuyn giao ny do BSC iu hnh. Chuyn giao gia cc thuc hai BSC khc nhau: Chuyn giao ny lin quan n c hai tng i MSC qun l hai BSC.. Chuyn giao gia hai thuc hai tng i MSC khc nhau: Chuyn giao ny lin quan n c hai tng i ph trch cc ni trn. Trong trng hp chuyn giao nhiu ln gia hai thuc hai MSC khc nhau, tng i MSC u tin ph trch MS c gi l tng i qu giang v cuc gi lun lun c chuyn mch qua tng i ny. Ln chuyn giao gia hai thuc hai tng i khc nhau th nht c gi l chuyn giao gia cc thuc hai tng i ln u, cn cc ln sau c gi l chuyn giao gia cc thuc hai tng i tip theo. Cc iu kin xy ra chuyn giao : Khi MS ang m thoi nhng di chuyn t vng ph sng ca BTS ny sang vng ph sng ca BTS khc. Khi cng trng ca BTS phc v gim dn, cng trng ca BTS k can tng dn. Nu MS tip tc di chuyn theo hng ngy th n mt thi im no th cng ca BTS phc v khng hot ng. Do mun tip tc m thoi th phi chuyn giao sang BTS k cn. Khi MS di chuyn nhng n ang trong vng ph sng l giao ca 2 BTS. Lc , nu v mt nguyn nhn no lm cho ch s bit li trn BTS ang phc v tng ln th h thng cng thc hin chuyn giao sang BTS mi ci thin cht lng. Chuyn giao ny gi l chuyn giao cht lng. Khi MS khng di chuyn nhng n ang trong vng ph sng l giao ca hai BTS. Lc nu lu lng trn BTS ang phc v bo ho hoc sp bo ho th h thng cng thc hin chuyn giao mt s MS sang BTS mi cho BTS ny c th phc v c cho cc MS mi. Chuyn giao ny gi l chuyn giao lu lng. 2.4 M T QU TRNH THIT LP CUC GI TRONG MNG GSM 2.4.1 TRM DI DNG MS THC HIN CUC GI MS yu cu n nh knh: Sau khi thc hin vic quay s, MS yu cu c n nh knh trn knh truy nhp ngu nhin RACH. Nht c yu cu ny trm thu pht gc BTS s gii m bn tin. Phn mm ca trm gc BSS n nh knh SDCCH vi bn tin n nh knh tc thi gi trn knh cho php truy nhp AGCH.

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MS tr li: MS tr li bn tin n nh knh tc thi v chuyn ti n nh knh SDCCH. Trn knh SDCCH, MS s truyn i cc bn tin SABM ( Set Asynchronous Balance Mode Kiu cn bng khng ng b t hp ). Bn trong bn tin SABM bao gm cc ch th yu cu cc dch v khc nhau nh bn tin yu cu thc hin cuc gi hay cp nht v tr. Cc bn tin ny s c x l ti trm gc BSS v c chuyn ti trung tm chuyn mch MSC thng qua giao din A. Yu cu nhn thc: Sau khi nhn c cc yu cu v dch v, trung tm chuyn mch MSC s gi i mt yu cu nhn thc i vi trm di ng MS. Cc yu cu dch v s c gi ti trm gc BSS thng qua ng bo hiu. Trm thu pht gc BTS s lm nhim v truyn cc yu cu ny ti MS trn knh iu khin chuyn dng c lp SDCCH. MS tr li nhn thc: Trm di ng MS tr li yu cu nhn thc bng mt p ng nhn thc. p ng tr li nhn thc ca MS s c trm thu pht gc BTS chuyn ti trung tm chuyn mch BSC trn ng bo hiu v tuyn. Yu cu m ha: Sau qu trnh nhn thc c hon thnh (qu trnh nhn thc c thc hin vi cc thut ton v kho bo mt dng trong GSM l A3, A4, A8 v Ki), MSC s gi n BSC mt lnh yu cu m ho qu trnh trao i thng tin gia MS v MSC ( Ciphering Mode Ch m ho ). Qu trnh ny c thit lp hay thng l ph thuc vo BSC v MSC thit lp ch m ho Ciphering Mode l ON hay OFF. Nu ch m ho l ON th thut ton A5.2 v Kc c s dng. Hon thnh qu trnh m ho: MS tr li hon thnh qu trnh m ho bng cch gi bn tin thc hin xong qu trnh m ho ( Ciphering Mode Complete). MS thit lp cuc gi: Trm di ng MS gi bn tin thit lp cuc gi trn knh iu khin chuyn dng c lp SDCCH, n gi ti tng i di ng MSC dch v yu cu thit lp cuc gi. Yu cu n nh knh lu lng: Sau khi tng i MSC nhn c bn tin yu cu thit lp cuc gi, MSC s gi li h thng BSS bn tin n nh knh lu lng. Bn tin ny ch th loi knh luCHNG 2

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lng s c yu cu l knh bn tc ( half rate ) hay ton tc ( full rate ) hoc truyn s liu (data). Trm thu pht gc BTS s ch nh v n nh cho MS mt knh lu lng TCH bng cch gi mt lnh n nh trn knh SDCCH. MS hon thnh vic n nh knh lu lng TCH: p ng lnh n nh knh, MS chim ly knh TCH v ng thi gi bn tin hon thnh vic n nh knh trn knh iu khin lin kt nhanh FACCH. Bn tin chung: Tng i di ng MSC gi bn tin chung ti my di ng MS. Bn tin ny thng bo MS hon thnh vic gi v c tn hiu hi m chung c nghe thy t MS. Bn tin ny l trong sut i vi h thng trm gc BSS. Bn tin kt ni: Khi bn b gi nhc my tr li th mt bn tin kt ni c gi n trm di ng MS. Tn hiu ny l trong sut i vi trm BSS. Bn tin kt ni c truyn thng qua knh iu khin lin kt nhanh FACCH. tr li tn hiu kt ni, MS m mt ng ting v truyn i thng qua knh FACCH, bn tin kt ni ti tng i di ng MSC v cuc gi c thc hin. 2.4.2 MS NHN CUC GI Nhn tin tm gi: Khi thu bao c tm gi th tng i di ng MSC s gi mt bn tin yu cu nhn tin ( Paging Request ) n h thng iu khin trm gc BSC. BSC s x l bn tin ny v truyn chng trn knh nhn tin PCH. Thu bao tr li: Sau khi thu c bn tin Paging Request, trm di ng MS tr li bng cch gi bn tin yu cu knh trn knh truy nhp ngu nhin RACCH. An nh knh iu khin chuyn dng c lp SDCCH: Nhn c bn tin n nh knh, BSS s x l bn tin v ngay lp tc n nh mt knh SDCCH. Vic n nh ny s c m ho v truyn trn knh cho php truy nhp AGCH. Trm di ng MS c n nh mt knh SDCCH v truyn mt bn tin kiu cn bng khng ng b t hp SABM tr li nhn tin. Mng s tr li trn ng ln (Uplink ) thit lp kt ni v tuyn lp th hai. Sau khi c x l ti phn BSS, bn tin tr li tm gi s c gi ti MSC.

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Yu cu nhn thc: Sau khi nhn c bn tin tr li tm gi, tng i di ng MSC s gi ti mt yu cu nhn thc i vi trm di ng MS. Yu cu nhn thc c gi ti trm gc BSS thng qua ng bo hiu. Trm thu pht gc BTS s lm nhim v truyn cc yu cu ny ti trm di ng MS trn knh iu khin chuyn dng c lp SDCCH. MS tr li nhn thc: MS tr li yu cu nhn thc bng mt p ng nhn thc. p ng tr li nhn thc ca MS s c BTS chuyn ti BSC trn ng bo hiu v tuyn. Yu cu m ho: Qu trnh nhn thc c hon thnh ( c thc hin vi thut ton v m kho dng trong GSM l A3, A4, A8 v Ki ), MSC s gi n BSC mt lnh yu cu m ho ( Ciphering Mode ) qu trnh trao i thng tin gia MS v MSC. Qu trnh ny c thit lp hay khng l ph thuc vo ch m ho do BSC v MSC thit lp ON hay OFF. Nu ch m ho l ON th thut ton A5.2 v Kc c s dng. Hon thnh qu trnh m ho: MS tr li hon thnh qu trnh m ho bng cch gi bn tin Hon thnh ch m ho ( Ciphering Mode Complete ). Bn tin thit lp: MSC gi bn tin thit lp ti MS yu cu cc dch v. BSS gi bn tin thit lp trn knh iu khin chuyn dng c lp SDCCH. MS xc nhn cuc gi: Khi nhn c thng tin v vic thit lp cuc gi, trm di ng MS gi i mt bn tin xc nhn cuc gi. Bn tin ny thng bo rng trm di ng MS nhn c bn tin thit lp cuc gi v cho bit MS c th nht cuc gi. An nh knh: Khi nhn c bn tin xc nhn, tng i di ng MSC gi mt bn tin n nh knh. H thng trm gc BSS nhn c bn tin ny n nh knh lu lng TCH v gi bn tin n nh knh ti trm di ng MS trn knh iu khin chuyn dng c lp SDCCH.

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Hon thnh n nh knh: Trm di ng MS chim ly knh TCH v gi bn tin hon thnh vic n nh knh iu khin lin kt nhanh FACCH ( y l mt knh logic trn knh TCH ). H thng trm gc BSS nhn bn tin ny v gi n n tng i di ng MSC. Bn tin chung: MS gi bn tin chung ti tng i di ng MSC trn knh iu khin lin kt nhanh FACCH. Bn tin ny thng bo tng i di ng MSC tm gi c trm di ng MS v MS ang chung. Tng i di ng MSC gi hi m chung ny cho my ch gi. MS thc hin kt ni: Khi trm di ng MS tr li, MS gi bn tin kt ni trn mt knh diu khin lin kt nhanh FACCH v thit lp mt ng thoi n ngi s dng. Bn tin kt ni c truyn qua BSS ti tng i di ng MSC trn ng bo hiu. Bn tin xc nhn kt ni c gi tr li tng i di ng MSC i n tng i ca my ch gi. Thit lp cuc gi thnh cng: Kt ni cuc gi c thit lp v cuc thoi c tin hnh.

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CHNG 3 TNG QUAN V TIN NHN SMS3.1 GII THIU V SMS SMS l t vit tt ca Short Message Service. l mt cng ngh cho php gi v nhn cc tn nhn gia cc in thoi vi nhau. SMS xut hin u tin Chu u vo nm 1992. thi im , n bao gm c cc chun v GSM (Global System for Mobile Communications). Mt thi gian sau , n pht trin sang cng ngh wireless nh CDMA v TDMA. Cc chun GSM v SMS c ngun gc pht trin bi ETSI. ETSI l ch vit tt ca European Telecommunications Standards Institute. Ngy nay th 3GPP (Third Generation Partnership Project) ang gi vai tr kim sot v s pht trin v duy tr cc chun GSM v SMS. Nh ni trn v tn y ca SMS l Short Message Service, t cm t , c th thy c l d liu c th c lu gi bi mt tin nhn SMS l rt gii hn. Mt tin nhn SMS c th cha ti a l 140 byte (1120 bit) d liu. V vy, mt tin nhn SMS ch c th cha : + 160 k t nu nh m ha k t 7 bit c s dng (m ha k t 7 bit th ph hp vi m ha cc l t latin chng hn nh cc l t alphabet ca ting Anh). + 70 k t nu nh m ha k t 16 bit Unicode UCS2 c s dng (cc tin nhn SMS khng cha cc k t latin nh k t ch Trung Quc phi s dng m ha k t 16 bit). Tin nhn SMS dng text h tr nhiu ngn ng khc nhau. N c th hot ng tt vi nhiu ngn ng m c h tr m Unicode , bao gm c Arabic, Trung Quc, Nht bn v Hn Quc. Bn cnh gi tin nhn dng text th tin nhn SMS cn c th mang cc d liu dng binary. N cn cho php gi nhc chung, hnh nh cng nhiu tin ch khc ti mt in thoi khc. Mt trong nhng u im ni tri ca SMS l n c h tr bi cc in thoi c s dng GSM hon ton. Hu ht tt c cc tin ch cng thm gm c dch v gi tin nhn gi r c cung cp, s dng thng qua sng mang wireless. Khng ging nh SMS, cc cng ngh mobile nh WAP v mobile Java th khng c h tr trn nhiu model in thoi. 3.2 TIN NHN SMS CHUI/ TIN NHN SMS DI Mt trong nhng tr ngi ca cng ngh SMS l tin nhn SMS ch c th mang mt lng gii hn cc d liu. khc phc tr ngi ny, mt m rng ca n gi l SMS chui (hay SMS di) ra i. Mt tin nhn SMS dng text di c th cha nhiu hn 160 k t theo chun dng trong ting Anh. C cu hot ng c bn SMS chui lm vic nh sau: in thoi di ng ca ngi gi s chia tin nhn di ra thnh nhiu phn nh v sau gi cc phn nh ny nh mt tin nhn SMS n. Khi cc tin nhn SMS ny c gi ti ch hon ton th n s c kt hp li vi nhau trn my di ng ca ngi nhn.CHNG 3

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Kh khn ca SMS chui l n t c h tr nhiu so vi SMS cc thit b c s dng sng wireless. 3.3 IU G LM CHO TIN NHN SMS TR LN RNG KHP Cc tin nhn SMS c th c gi v c ti bt k thi im no. Ngy nay, hu ht mi ngi u c in thoi di ng ca ring mnh v mang n theo ngi hu nh c ngy. Vi mt in thoi di ng , bn c th gi v c cc tin nhn SMS bt c lc no bn mun, s khng gp kh khn g khi bn ang trong vn phng hay trn xe bus hay nh Tin nhn SMS c th c gi ti cc in thoi m tt ngun. Nu nh khng chc cho mt cuc gi no th bn c th gi mt tin nhn SMS n bn ca bn thm ch khi ngi tt ngun my in thoi trong lc bn gi tin nhn . H thng SMS ca mng in thoi s lu tr tin nhn ri sau gi n ti ngi bn khi in thoi ca ngi bn ny m ngun. Cc tin nhn SMS t gy phin phc trong khi bn vn c th gi lin lc vi ngi khc Vic c v vit cc tin nhn SMS khng gy ra n o. Trong khi , bn phi chy ra ngoi khi rp ht, th vin hay mt ni no thc hin mt cuc in thoi hay tr li mt cuc gi. Bn khng cn phi lm nh vy nu nh tin nhn SMS c s dng. Cc in thoi di ng v chng c th c thay i gia cc sng mang Wireless khc nhau. Tin nhn SMS l mt cng ngh rt thnh cng v trng thnh. Tt c cc in thoi mobile ngy nay u c h tr n. Bn khng ch c th trao i cc tin nhn SMS i vi ngi s dng mobile cng mt nh cung cp dch v mng sng mang wireless, m ng thi bn cng c th trao i n vi ngi s dng khc cc nh cung cp dch v khc. SMS l mt cng ngh ph hp vi cc ng dng Wireless s dng cng vi n. Ni nh vy l do: Th nht, tin nhn SMS c h tr 100% bi cc in thoi c s dng cng ngh GSM. Xy dng cc ng dng wireless trn nn cng ngh SMS c th pht huy ti a nhng ng dng c th dnh cho ngi s dng. Th hai, cc tin nhn SMS cn tng thch vi vic mang cc d liu binary bn cnh gi cc text. N c th c s dng gi nhc chung, hnh nh, hot ha Th ba, tin nhn SMS h tr vic tri tr cc dch v trc tuyn. Ngha l n cho php thc hin vic chi tr cc dch v trc tuyn mt cch thun li. V d nh, bn mun pht trin mt ng dng download nhc chung mang tnh thng mi v thu ph s dng t ngi s dng cho mi ln download nhc chung . Mt cch rt thun li thc thi ng dng ny l s dng mt s in thoi t nh cung cp mng c kh nng tri tr ngc li ti tin ch ny thng qua vic s dng mt sngCHNG 3

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mang wireless. V c th ti nhc chung ny ngi s dng phi son mt tin nhn c ni dng cng nh cu trc tin nhn c qui nh bi nh cung cp dch v v gi tin nhn ny ti mt s in thoi c tch hp sn chc nng tri tr trc tuyn m ngi pht trin ng dng xy dng. ng dng SMS m bn s dng sau s gi tr li cho bn mt hay nhiu tin nhn SMS c km theo c nhch chung (chng hn ) v thng bo chi ph phi tr cho vic s dng ng dng . Chi ph ny s gm c chi ph s dng dch v hng thng ca in thoi di ng ny hay l c khu tr t th card dng di ng ca bn. N ty thuc vo tha thun gia bn v ngi pht trin ng dng . 3.4 SMS CENTRE/SMSC Mt SMS Center (SMSC) l ni chu trch nhim lun chuyn cc hot ng lin quan ti SMS ca mt mng wireless. Khi mt tin nhn SMS c gi i t mt in thoi di ng th trc tin n s c gi ti mt trung tm SMS. Sau , trung tm SMS ny s chuyn tin nhn ny ti ch (ngi nhn). Mt tin nhn SMS c th phi i qua nhiu hn mt thc th mng (netwok) (chng hn nh SMSC v SMS gateway) trc khi i ti ch thc s ca n. Nhim v duy nht ca mt SMSC l lun chuyn cc tin nhn SMS v iu chnh qu trnh ny cho ng vi chu trnh ca n. Nu nh my in thoi ca ngi nhn khng trng thi nhn (bt ngun) trong lc gi th SMSC s lu tr tin nhn ny. V khi my in thoi ca ngi nhn m ngun th n s gi tin nhn ny ti ngi nhn. Thng th mt SMSC s hat ng mt cch chuyn dng chuyn lu thng SMS ca mt mng wireless. H thng vn hnh mng lun lun qun l SMSC ca ring n v v tr ca chng bn trong h thng mng wireless. Tuy nhin h thng vn hnh mng s s dng mt SMSC th ba c v tr bn ngoi ca h thng mng wireless. Bn phi bit a ch SMSC ca h thng vn hnh mng wireless s dng, tinh chnh chc nng tin nhn SMS trn in thoi ca bn. in hnh mt a ch SMSC l mt s in thoi thng thng hnh thc, khun mu quc t. Mt in thoi nn c mt thc n chn la cu hnh a ch SMSC. Thng thng th a ch c iu chnh li trong th SIM bi h thng mng wireless. iu ny c ngha l bn khng cn phi lm bt c thay i no vi c. 3.5 NHN TIN SMS QUC T Cc tin nhn SMS gia cc nh iu hnh c chia ra lm hai hng mc gm tin nhn SMS gia cc nh iu hnh cc b v tin nhn SMS gia cc nh iu hnh quc t vi nhau. Tin nhn SMS gia cc nh iu hnh cc b l tin nhn m c gi gia cc nh iu hnh trog cng mt quc gia cn tin nhn SMS gia cc nh iu hnh quc t l tin nhn SMS c gi gia cc nh iu hnh mng wireless nhng quc gia khc nhau.

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Thng th chi ph gi mt tin nhn SMS quc t th cao hn so vi gi trong nc. V chi ph gi tin nhn trong ni mng th t hn so vi gi cho mng khc trong cng mt quc gia khi AND 192.168.20.50 vi 255.255.255.0 kt qu l 192.168.20.0. My trm sau s thc hin php tnh AND gia a ch ch vi Subnet Mask ging trn. TCP/IP sau s so snh kt qu nhng gi tr t 2 php tnh AND. Nu 2 gi tr ng nht th Trm TCP/IP kt lun ch kia l trn Subnet cc b. Nu 2 gi tr khc nhau th trm xc nh ch kia l xa. Ta cng c 1 cch vit khc xc nh Subnet Mask l: a ch IP/Tin t mng Tin t mng c xc nh bng cch cng tt c cc bit 1 trong dy 32bit ca Subnet Mask. V d: 192.168.5.10 c Subnet Mask mc nh l 255.255.255.0. i qua s nh phn s l 11111111 11111111 11111111 00000000. => Tng cng c 24 bit 1. Vy ta c th vit di dng:192.168.5.10 / 24 Bng 5: Nhng Subnet Mask mc nh cho cc Lp mng

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4.7 DEFAULT GATEWAY Khi 1 trm trong TCP/IP cn truyn thng tin vi 1 Trm trn mng khc th n phi thng qua 1 Router. Router c gn nhiu Interface (vd Card Mng) kt ni n cc Mng ring bit, Routing l qu trnh nhn nhng gi IP ti 1 Interface v gi nhng gi ny ra 1 Interface khc hng v 1 ch cui cng. Vi 1 host c cp trn mng TCP/IP th Default Gateway l a ch ca Router, nm trong 1 phm vi Broadcast, n c cu hnh a nhng lung IP n Mng khc. Khi 1 my tnh c gng truyn t thng tin n 1 trm khc trn Mng IP, my tnh s dng SUBNET MASK xc nh trm ch l Cc B (Local) hay Xa (Remote). Nu ch l 1 trm trn 1 phn on Mng Cc B, my tnh s n gin gi 1 gi tin n Mng Cc B bng cch truyn cho tt c (Broadcast). Nu ch l 1 Trm xa, my tnh s a gi tin n Default Gateway c xc nh trong TCP/IP Properties. Router c ghi r ti a ch Default Gateway sau s chu trch nhim a gi tin n mng 1 cch chnh xc. 4.8 CHIA SUBNET Nhng Subnet Mask c s dng bi nhiu host xc nh u l phn chia ca 1 a ch IP c xem nh l Net ID ca a ch .Lp A, B v C s dng Subnet Mask mc nh c che ln lt l 8, 16, 24bit tng ng vi nhng a ch 32bit. Mt mng cc b c nh r bi 1 Subnet Mask hay cn gi l 1 Subnet. Chia subnet l phng php logic chia 1 a ch mng bng cch tng bit 1 s dng trong Subnet Mask ca 1 mng. Phn m rng ny cho php bn chia nhiu Subnet bn trong mng ban u +255.255.0.0 l Subnet Mask mc nh c s dng cho nhng host bn trong lp B , v d nh 131.107.0.0, th 2 a ch 131.107.1.11 v 131.107.2.11 l ging Subnet. V nhng host trong Net ny lin lc vi nhau bng cch gi gi tin Broadcast. Nhng khi Subnet Mask c tng thm thnh 255.255.255.0 th r rng 2 a ch 131.107.1.11 v 131.107.2.11 l khc Net. Th nhng host ny mun lin lc vi nhau th phi gi 1 gi tin IP n Default Gateway, ci m n chu trch nhim routing nhng gi d liu n Subnet ch. + Trong khi ban u a ch lp B khi cha chia Subnet c 65.534 host th Subnet Mask mi c cu hnh nh hnh bn di cho php bn chia thnh 256 Subnet vi 254 host trn 1 subnet.

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Hnh 21.Minh ha u im ca chia Subnet + u im ca vic chia Subnet l khi chia xong nhng phn on con c th tri rng trn nhiu phn on vt l (vd mng c th gm 2 phn on l Ethernet v Token Ring). Tuy nhin u im chnh l gim lu lng mng v khi chia Subnet th lu lng cc gi tin Broadcast khng lm nh hng n ton mng do Router gia cc mng s chn cc gi tin Broadcast. Xc nh Tng s Host trn 1 Mng bng cch ta ly 2 ly tha s bit lm Host ID sau tr cho 2. V d: 192.168.1.0 thuc lp C nn mc nh s c 24bit lm Net ID (192.168.1.0/24) v 8bit lm Host ID. Vy Tng s Host : 2 ly tha 8 2 = 254 Host Xc nh Tng s Subnet bng cch ta ly 2 ly tha s bit m rng thm vo Net ID V d: 172.16.0.0. Thuc lp B nn c 16bit lm Net ID(172.16.0.0/16) v 16bit lm Host ID. Do Net ID cha m rng bit no nn s bit m rng = 0 , vy Tng s Subnet = 2 ly tha 0 = 1 Subnet Vy nu 172.16.0.0 vit di dng 172.16.0.0/20. Vy c ngha s bit lm Host ID l 12 v s bit m rng thm vo Net ID l 4. => Tng S Host : 2 ly tha 12 2 = 4094 Hosts => Tng S Subnet : 2 ly tha 4 = 16 Subnets Xc nh s Host trn mi Subnet: Tnh tng s Host trn 1 Subnet ging nh tnh tng s Host trn 1 Mng. Khi 1 a ch Mng c chia Subnet. Th tng s Host trn mi Subnet s l 2 ly tha x -2 vi x l s bit lm Host ID.

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c lng phm vi a ch Subnet: Bng cch s dng K Hiu Thp Phn Du Chm , ta c th c lng c phm vi ca nhng a ch IP trn mi Subnet n gin bng cch ta ly 256 tr cho gi tr b 8 thch hp trong Subnet Mask. V d 1: 1 Net thuc lp C c a ch 192.168.5.0 vi Subnet Mask l 255.255.255.192. Ta ly 256-192 = 64, Vy kt qu mi phm v a ch Subnet ca Mng c nhm trong khong 64: 192.168.5.0 192.168.5.63, 192.168.5.64 192.167.5.127, .v.v V d 2: 1 Net thuc lp B c a ch 172.16.0.0 vi Subnet Mask l 255.255.255.240. Ta ly 256-240 = 16. Bi vy, mi phm vi a ch Subnet c nhm 16 v tr th 3 v thch hp b 8. Nhng tri li v tr th 4 ca b 8 c phm vi t 0-255: 172.16.0.0 172.16.15.255, 172.16.16.0 172.16.31.255, - Lu rng c 2 a ch khng c dng cp cho Host l a ch mng (tt c cc bit trong phn Host ID u l 0) v a ch Broadcast (tt c cc bit trong phn Host ID u l 1) 4.9 SUPERNETTING ngn s cn dn cc Net ID ca lp A,B. Cc nh iu hnh Internet sp t 1 s gi l Supernetting. Supernetting s cho php nhiu Net gp thnh 1 Net. Supernetting a ra nhiu thun li hiu qu cho vic t a ch cho cc Net. V d: gi s 1 t chc cn cung cp khong 2000 Trm. Con s ny l qu ln i vi 1 lp C (ch c th cp cho 254 trm). Tuy nhin 1 Net thuc lp B c th cp ti 16384 Net vi 65534 trm trn mi Net v con s ny cng s nhanh chng gim bt. Bi vy n khng thit thc 1 ISP (Internet Service Provider) cp 1 Net lp B v nhu cu t chc kia ch chim 3% trong tng s IP ca 1 Net trong lp B , c ngha l lng ph mt 63534 a ch. Bng cch s dng Supernetting, 1 ISP c th cp 1 khi nhng a ch lp C (1 Net c 254 Hosts) m n c xem nh 1 mng c lp u gia lp B v lp C. Trong v d ny, 1 khi gm 8 Net thuc lp C c th p ng nhu cu t chc kia bng cch cp 2032 host. Supernetting khc vi chia Subnet ch l Supernetting mn nhng Bit Net ID em qua lm Host ID. V d: gi s 1 ISP cp cho bn 1 khi gm 8 Net lp C t 207.46.168.0 dn 207.46.175.0. Gn 1 Subnet Mask l /21 (mc nh l /24) n cc Router ti ISP v n tt c cc host nm trong t chc ca bn, kt qu l tt c cc my u thy nhau nh l 1 Net bi v nh vo Net ID b rt ngn pht sinh t subnet mask l /24, phn Net ID ca ton b 8 a ch ny by gi c nhn thy nh l duy nht.

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Hnh 22.Supernetting 4.10 CIDR (CLASSLES INTER-DOMAIN ROUTING) NH TUYN LIN VNG KHNG PHN LP CIDR l 1 phng php hiu qu tnh ton cc supernet bn trong nhng bng nh Tuyn. Nu khng dng CIDR, nhng bng nh Tuyn s ghi vo 1 mc ring x l mng nguyn bn trong supernet. CIDR cho php ton b supernet c x l ch bng 1 mc duy nht.

Hnh 23.nh tuyn lin vng khng phn lp Tri vi phng php phn lp. CIDR s dng K hiu nh phn ngha l tt c a ch IP v Subnet Mask c chuyn i thnh 0 v 1 to nn 32 gi tr thay v 4 gi tr nh ban u (v d: 172.16.2.2->10101100 00010000 00000100 00000010). Cu trc ny cho kch thc mng linh hot hn v ti u vic gn a ch IP

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VD: 10.217.123.7 chuyn sang nh phn ta c 00001010 11011001 01111011 00000111. Lm tng t vi Subnet Mask chng hn l 255.255.240.0 ta c 11111111 11111111 11110000 00000000. Sau ta s AND 2 gi tr thp phn va chuyn tnh phn Net ID. Vy ta c 00001010 11011001 01110000 00000000. Sau chuyn sang h Thp phn ta c 10.217.112.0. Ta cng tt c cc bit1 li , cui cng ta c 10.217.112.0/20 Phng php CIDR lun cn c a ch IP v Subnet Mask xc nh c 1 a ch bt k cng Net hay khc Net. 4.11 VARIABLE LENGTH SUNET MASKS (SUBNET MASKS C CHIU DI THAY I) Theo cch truyn thng th 1 Subnet Mask n c chia s qua mi host v router trong 1 t chc. Khi 1 Subnet Mask n c s dng khp ton b mng, mng c th b hng bn trong nhng subnet, v nhng subnet ny c cng s host bi v n dng Subnet Mask ging nhau. iu ny l ko hiu qu. Tuy nhin, vi Variable-Length Subnet Masks (VLSMs) th cc router trong 1 t chc c th qun l nhng Subnet Mask khc nhau. Thng thng nht, VLSMs c dng cho php t cc subnets chia thnh subnet nh hn, hay ni cch khc, VLSMs cn c gi l Chia subnet trong 1 subnet ln hn tn dng ti a a ch. hiu r vn ny, ta s lm 1 v d: Gi s 1 cng ty c 3 vn phng A(50 host), B(27 host), C(12 host) v D(12 host) nh hnh bn di. Lm th no tn dng ti a khng gian a ch

Hnh 24.Subnet mask chiu di thay i Theo bi th 1 a ch mng lp C 192.168.100.0/24 ph hp c cp. Ta s tin hnh m rng Net ID bng cch ly s bit Host ID a qua Net ID. Cc bc lm nh sau:CHNG 4

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B1: Xc nh bao nhiu bit Host ID s cn p ng Net ln nht B2: Ly 1 subnet cp cho Net ln nht B3: Chn Net ln k tip lm vic B4: Chn Net ln th 3 lm vic Ta bt u tin hnh lm B1: + Ta nhn thy vn phng A l Net ln nht vi 50 host. Do , bn cn bit bao nhiu bit Host ID s cn: Nu 2 ly tha H 2 = S host hp l trn mi subnet Sau , 2 ly tha H 2 >= 50 Do H = 6 (6 l gi tr nh nht hp l): + Bn cn 6 bit lm Host p ng yu cu ca vn phng A + Nu bn cn 6 bit Host v bn bt u vi 8 bit Net, th 8-6 = 2 bit Net to ra cc subnet Bt u vi: NNNNNNNN (y l 8 bit trong b 8 th 4) V by gi : NNHHHHHH Ta tin hnh B2: + Ta c 2 bit Net lm vic vy ta c 2 ly tha 2 = 4 Subnets : NN = 00HHHHHH (6 bit H bn cn cho vn phng A) 01HHHHHH 10HHHHHH 11HHHHHH + Nu bn cng tt c cc s 0 vo bit H bn s c s Mng cho 4 subnet: 00000000 = .0 01000000 = .64 10000000 = .128 11000000 = .192 + y l tt c cc subnet m bn c ging Subnet Mask + 2 bit ly t Host ID sang Net ID. Vy Subnet Mask l:CHNG 4

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11111111 11111111 11111111 11000000 hay 255.255.255.192 hay /26 + Ly 1 subnet cho vn phng A. Ta cn li 3 Subnet Bng 6: Chia Subnet Mask

Ta tin hnh B3: Chn Net ln k tip lm vic + Ta thy vn phng B ph hp yu cu vi 27 host + Xc nh s bit Host ID cn cho Net ny: 2 ly tha H 2 >= 27 ; H = 5 + Bn cn 5 bit Host p ng yu cu vn phng B + Bn bt u vi m hnh 2 bit Net v 6 bit Host cho Vn Phng A. + Bn ly 1 trong cc Net /26 cn li chia cho Vn Phng B + Vi mc ch ca bi, ta chn mng .128/26: 10000000 + Nhng bn cn 5 bit , khng phi 6 bit. Do bn cn thm 1 bit N bn tri: 10N00000 Khi : * 10 i din m ta cho phn nguyn thy ca chia Subnet * N i din cho bit m rng * 00000 i din cho 5 bit Host bn cn cho vn phng B + Bi v bn c bit m rng ny, bn phi to ra 2 subnet nh hn t subnet nguyn thy: 10000000 10100000 + Chuyn qua h thp phn, nhng subnet ny l: 10000000 = .128 10100000 = .160 Bn c subnet c chia trong subnet. y l dng c bn ca VLSMs Mi subnet c chia trong subnet s c 1 Subnet Mask mi. Nguyn thy ban u Subnet Mask l /24 c thay i thnh /24 bn trong Net A. Sau bn ly 1 trong nhng mng Subnet /26 v tch n ra thnh 2 mng subnet /27: 10000000 v 10000000 vi 3 bit Net v 5 bit HostCHNG 4

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V Mask by gi s bng: 11111111.11111111.11111111.11100000 Hay 255.255.255.224 Hay /27 Ly 1 trong nhng subnet c chia trong subnet cho vn phng B: 10000000/27 = Network B S dng 1 subnet c chia trong subnet cn li s dng v sau hay bn c th chia nh ra tip nu bn cn. Bn mun bo m nhng a ch s khng b trng lp. Bn tr li vi Bng nguyn thy trn: Bng 7: Chia Subnet Mask

By gi bn c th chia mng .128/26 thnh 2 mng /27 nh hn v cp cho vn phng B Bng 8: Chia Subnet Mask

Nhng mng cn li th vn c sn cp cho nhng mng hay subnet thm na kt qu tt hn. Ta tin hnh B4: Chn Net ln th 3 lm vic + Vn phng C v D mi vn phng 12 host + Xc nh bit Host cn cho cc mng ny: 2 ly tha H 2 >= 12 ;H = 4 + Bn cn 4 bit p ng yu cu ca Vn Phng C v D + Bn bt u vi m hnh 2 bit Net v 6 bit Host cho Vn Phng A + By gi bn phi la chn ly Mng no. Bn c th ly 1 mng /26 khc hoc cng c th ly 1 mng /27 v th xem n c va vi yu cu ko.

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+ Vi mc ch ca Bi, ta chn 1 mng /27 .160/27: 10100000 (bit 1 v tr th 3 khng cn c t m nh trn v by gi n l phn ca bit Net) + Nhng bn ch cn 4 bit Host, khng phi 5. Do bn cn thm 1 bit N bn tri: 101N0000 Khi * 101 i din m ta cho phn nguyn thy ca Subnet * N i din cho bit m rng * 0000 i din cho 4 bit Host bn cn cho vn phng C, D + Bi v bn c bit m rng ny, bn phi to ra 2 subnet nh hn t subnet nguyn thy: 10100000 10110000 + Chuyn qua h thp phn, nhng subnet ny l: 10100000 = .160 10110000 = .176 Mi subnet c chia trong subnet s c 1 Subnet Mask mi. Mi subnet c chia trong subnet by gi c 4 bit Net v 4 bit Host v Mask mi ca chng l: 11111111.11111111.11111111.11110000 hay 255.255.255.240 hay /28 Ly 1 trong nhng subnet c chia trong subnet mi to ra cho vn phng C v D Bng 9: Chia Subnet Mask cho cc lp

4.12 NGUYN L HOT NG CA GIAO THC TCP/IP V INTERNET Mng my tnh ngy nay tr thnh mt thnh phn quan trng trong ngnh truyn thng. Trn th gii, ban u ch c vi mng my tnh c a vo s dng ccCHNG 4

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vin nghin cu v phc v cho quc phng. Cng vi thi gian, khoa hc pht trin, gi my gim, mng my tnh c mt khp ni, t trng hc, nh my n cc hc vin. c bit s bng n ca mng thng tin ton cu Internet a kh nng s dng mng n tng ngi dn. Hng ngy bn do chi trn Internet, lt trn cc trang Web, c bao gi bn t hi lm th no m con ngi c c kh nng truy cp thng tin mnh m v tin li n nh vy? Tr li y cu hi ny qu l khng n gin v l thnh qu ca hng ngn con ngi, lao ng trong hng chc nm, khng th trnh by gi gn ch trong vi trang vit. M hnh tng qut ca mng Internet Nh trong hnh 1, kt cu vt l ca mng Internet gm c mng chnh cha cc server cung cp dch v cho mng, mng nhnh bao gm cc trm lm vic s dng dch v do Internet cung cp. "m my Internet" hm cha v vn mng chnh, mng nhnh v bao ph ton th gii. mt h thng phc tp nh vy hot ng trn tru v hiu qu th iu kin tin quyt l mi my tnh trong mng, d khc nhau v kin trc, u phi giao tip vi mng theo cng mt quy lut. l giao thc TCP/IP:

Hnh 25.Kt cu vt l ca mng Qu trnh truyn d liu qua mng Internet

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Nu tng lp trnh, bn hn bit rng mt chng trnh hon chnh c to nn t nhiu module vi cc chc nng v nhim v khc nhau nhng li lin kt cht ch vi nhau. Qu trnh truyn d liu cng nh vy. c th truyn qua mng Internet, d liu phi c x l qua nhiu tng. Mt mng intranet theo chun OSI thng c by tng nhng Internet ch c bn tng x l d liu l: * Tng application * Tng transport cn gi l tng TCP (Transmission Control Protocol) * Tng network cn gi l tng IP (Internet Protocol) * Tng Datalink/Physical Gi s bn ang my A v mun gi mt thng ip ti my B. Bn dng mt trnh son tho vn bn son th, sau nhn nt Send. Tnh t thi im d liu c x l ln lt nh trong hnh 2.

Hnh 26.ng i ca mng u tin, d liu c x l bi tng application. Tng ny c nhim v t chc d liu theo khun dng v trt t nht nh tng application my B c th hiu c. iu ny ging nh khi bn vit mt chng trnh th cc cu lnh phi tun theo th t v c php nht nh th chng trnh mi chy c. Tng application gi d liu xung tng di theo dng byte ni byte. Cng vi d liu, tng application cng gi xung cc thng tin iu khin khc gip xc nh a ch n, i ca d liu. Khi xung ti tng TCP, dng d liu s c ng thnh cc gi c kch thc khng nht thit bng nhau nhng phi nh hn 64 KB. Cu trc ca gi d liu TCP gm mt phn header cha thng tin iu khin v sau l d liu. Sau khi ng gi xong tng TCP, d liu c chuyn xung cho tng IP.CHNG 4

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Gi d liu xung ti tng IP s tip tc b ng gi li thnh cc gi d liu IP nh hn sao cho c kch thc ph hp vi mng chuyn mch gi m n dng truyn d liu. Trong khi ng gi, IP cng chn thm phn header ca n vo gi d liu ri chuyn xung cho tng Datalink/Physical. Khi cc gi d liu IP ti tng Datalink s c gn thm mt header khc v chuyn ti tng physical i vo mng. Gi d liu lc ny gi l frame. Kch thc ca mt frame hon ton ph thuc vo mng m my A kt ni. Trong khi chu du trn mng Internet, frame c cc router ch dn c th ti ng ch cn ti. Router thc ra l mt module ch c hai tng l Network v Datalink/Physical. Cc frame ti router s c tng Datalink/Physical lc b header m tng ny thm vo v chuyn ln tng Network (IP). Tng IP da vo cc thng tin iu khin trong header m n thm vo quyt nh ng i tip theo cho gi IP. Sau gi IP ny li c chuyn xung tng Datalink/Physical i vo mng. Qu trnh c th tip tc cho n khi d liu ti ch l my B. Khi ti my B cc gi d liu c x l theo quy trnh ngc li vi my A. Theo chiu mi tn, u tin d liu qua tng datalink/physical. Ti y frame b b i phn header v chuyn ln tng IP. Ti tng IP, d liu c bung gi IP, sau ln tng TCP v cui cng ln tng application hin th ra mn hnh. H thng a ch v c ch truyn d liu trong mng Internet mt gi d liu c th i t ngun ti ch, mng Internet dng mt h thng nh a ch tt c cc my tnh ni vo mng nh hnh 3.

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Hnh 27.H thng tn v a ch ca mng Internet Nhng tn v a ch ny c gi cho my tnh nhn d liu. phn tch h thng tn/a ch, hy bt u t thp ln cao: 4.12.1 A CH VT L HAY CN GI L A CH MAC S d c tn gi nh vy l v a ch ny gn lin vi phn cng v i din cho mt thit b. Thng thng a ch vt l c t ngay trn bng mch my tnh hay trn thit b kt ni trc tip vi my (modem, card mng...)

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Hnh 28.a ch IP vt l a ch vt l c s dng nh sau: Thit b nhn d liu kim tra a ch vt l ch ca gi d liu tng vt l. Nu a ch ch ny ph hp a ch vt l ca thit b th gi d liu s c chuyn ln tng trn, nu khng n s b b qua. 4.12.2 SAP Dng i din cho giao thc bn trn tng MAC, y l IP. 4.12.3 A CH MNG( NETWORK ADDRESS) Mt thc th trong mng c xc nh ch qua a ch mng m khng cn a ch vt l. D liu c truyn qua mng ch da vo a ch mng. Khi no d liu ti mng LAN th a ch vt l mi cn thit a d liu ti ch. V d: My gi c a ch 128.1.6.7 ->a ch mng l 128.1 My nhn c a ch 132.5.8.12 ->a ch mng l 132.5 Mng Internet c trch nhim da vo 2 a ch mng trn a d liu ti mng 132.5. Khi ti mng 132.5 th da vo a ch 8.12 s tm ra a ch vt l thc truyn d liu ti ch. Nh vy c mt thc mc l: c a ch vt l ri, ti sao li cn thm a ch mng? Vic tn ti 2 loi a ch l do cc nguyn nhn: * 2 h thng a ch c pht trin mt cch c lp bi cc t chc khc nhau.

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* a ch mng ch c 32 bit s tit kim ng truyn hn so vi a ch vt l 48 bit. * Khi mch my hng th a ch vt l cng mt. * Trn quan im ngi thit k mng th s rt hiu qu khi tng IP khng lin quan g vi cc tng di. Nh trn ni, t a ch mng c th tm c a ch vt l. Cng vic tm kim ny c thc hin bi giao thc ARP (Address Resolution Protocol). Nguyn tc lm vic ca ARP l duy tr mt bng ghi tng ng a ch IP - a ch vt l. Khi nhn c a ch IP, ARP s dng bng ny tm ra a ch vt l. Nu khng thy, n s gi mt gi d liu, gi l ARP request, cha a ch IP vo mng LAN. Nu my no nhn ARP request v nhn ra a ch IP ca mnh th s gi li mt gi d liu cha a ch vt l ca n. Vy t a ch vt l, mt my tnh trong mng c th bit a ch IP ca mnh hay khng? Cu tr li l c. Giao thc gi l RARP (Reverse Address Resolution Protocol) thc hin cng vic ny. Gi s trong mng c mt my cn bit a ch IP ca mnh, n gi mt gi d liu cho tt c cc my trong mng LAN. Mi my trong mng u c th nhn gi d liu ny, nhng ch c RARP server mi tr li thng bo cha a ch mng ca my . Trn thc t, khi mun nhp vo mt a ch Internet no , bn hay nh vo dng ch nh "WWW.hotmail.com" m t thy nhng dng a ch s kh khc. Vy c iu g mu thun? Chng sao c, Internet dng mt h thng gi l DNS (Domain Name System) t tn cho mt host v cung cp mt s giao thc chuyn i t a ch ch ra a ch s v ngc li. Cch t chc tn ca DNS tun theo dng hnh cy nh hnh di.

Hnh 29.S DNS Mt my tnh trong mng s ng vi mt nt ca cy. Nh cy trn, my l FPT s c a ch hon chnh l fpt.com.vn. Mi nt trn cy biu din mt minCHNG 4

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(domain) trong h thng DNS; mi min li c mt hay nhiu min com. Ti mi min ny u phi c my ch DNS tng ng qun l h thng tn trong min . hiu r hn hot ng ca DNS, ly mt v d sau: Mt my trm c tn l test.fpt.com.vn mun bit a ch IP ca my www.microsoft.com, qu trnh hi ca n nh sau: Khi my test.fpt.com.vn gi yu cu hi v my www. microsoft.com ti DNS ca min fpt.com.vn, DNS xc nh l tn khng nm trong min m n qun l v gi ngc ln cho min mc cao hn l com.vn. Ti y, DNS cng khng tm c thng tin tho mn nn phi hi ngc ln DNS ca min vn. Qu trnh c th tip din n khi cu hi c gi ti DNS ca min microsoft.com v ti y cu hi c gii p. hot ng hiu qu nh trn, mi my ch DNS lu tr mt c s d liu gm cc bn ghi cha thng tin: + Tn ca DNS cp cao hn + a ch IP + a ch dng ch tng ng Ch s ca bn ghi c ly t a ch IP tng ng, nh t a ch IP c th d dng tm ra a ch ch 4.12.4 PROTOCOL ID Ch ra giao thc ca tng giao vn. Trn Internet trng ny l TCP hoc UDP. 4.12.5 PORT L mt s c trng cho mt chng trnh chy trn Internet. V d, chng trnh ly th in t qua giao thc IMAP c port=143, truyn file c port =21, v.v... 4.12.6 USERNAME L tn ngi ng k s dng chng trnh. phn II c ni ti router, n s dng cc thng tin iu khin trong header ca gi d liu IP quyt nh ng i tip theo ca gi ny. C rt nhiu thng tin iu khin nhng y ch xin phn tch cc thng tin quan trng. u tin l a ch ch. Nu a ch ch trng vi a ch ca router th gi d liu c truyn trc tip cho host B. Nu khng trng th d liu s c truyn n router tip theo trn ng i. Vn l router no c chn. C 2 kh nng la chn router, tc l 2 kh nng dn ng:

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+ Th nht l tun theo mt cch nghim ngt source routing. D liu s c truyn cho router tip theo trong source routing. Nhng d liu ch c truyn i khi router c chn c trong bng cc router c th n c ca router hin ti, bng khng s sinh ra li. + Th hai l "qun i" source routing v tm ng mi ti ch. Router tip theo c chn da trn s tm ng ny. Thng thng s tm ng da trn thut ton Dijstra tm kim theo chiu rng. Trn thc t, cch ny ang c s dng rng ri v c th tr thnh chun trong tng lai. Cc gi d liu IP thng c kch thc ph thuc vo mng con. Cc mng con khc nhau th kch thc gi IP ca chng cng khc nhau. Vy gi s mng A truyn c gi d liu c kch thc ln nht l 1024 byte, mng B truyn c gi d liu c kch thc ln nht l 256 byte th gi d liu t mng A c kch thc 1024 byte qua mng B nh th no? gii quyt vn ny, IP cung cp kh nng phn v gom mnh gi d liu. y chnh l lc IP s dng trng flags v offset trong gi d liu IP. Trng flags thc cht l cc c thng bo gi d liu ny c b phn mnh hay khng, trng offset cha gi tr tng i ca gi con trong gi to ban u. Khi phn mnh cc c c bt ln, ng thi trng offset c thit lp gi tr. Da vo cc d liu trn, IP c th d dng gom mnh gi d liu, hi phc khi d liu to ban u. Kim sot li Qua cc phn trn ta thy qu trnh d liu i trn mng kh r rng nhng trn mt mng rng ln nh Internet th c g m bo d liu s ti ch mt cch an ton? iu g xy ra nu trn ng i cc gi d liu b mt, tc nghn, lc ng...? y ch n thun l cc s c, nhng tht ng tic l n li rt hay xy ra trn thc t, do mt yu cu t ra l phi c c ch thng bo v sa li trn mng. Khi c li, tng IP n thun hu b d liu v thng bo li. Thng bo li c thc hin qua mt giao thc gi l ICMP (Internet Control Message Protocol). ICMP c th coi l bn ng hnh vi IP v c mt s c im sau: - Dng IP truyn thng bo qua mng - Khng c chc nng sa li m ch n thun l my thng bo li. Chc nng sa li l ca tng trn (tng TCP) - Thng bo li v gi d liu IP nhng li khng th thng bo li v gi d liu ca chnh mnh - Nu gi d liu IP b phn mnh th khi xy ra li, ICMP ch thng bo li ca mnh u tin

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Ni rng vic sa li l ca TCP nhng tht ra TCP chng sa li g c, khi c li xy ra n ch lm mi mt vic l truyn li. Hy xem n lm vic nh th no. TCP truyn d liu theo c ch "flow window". Tt c cc byte truyn u c nh s th t v TCP qun l vic truyn d liu da vo s th t . Gi s c 13 byte d liu gi cho my B.

Hnh 30.Gi 13 byte d liu theo chun TCP Byte 0 gi i v c xc nhn l ti ni. S xc nhn ny c thc hin bng cch khi nhn c d liu gi n, my B s gi mt thng bo v cho my gi. Thng bo c cha s th t ca byte c chp nhn cha trong trng ACK. Byte 1, 2 c gi nhng cha c xc nhn, cc byte 3, 4, 5 trong khung s c truyn i, cc byte t 6 tr i khng th c truyn. Gi tr window limit c tnh bng cng thc sau: Window limit=SND UNA + SND WND SND UNA = s byte gi i nhng cha c xc nhn SND WND= s byte trong , gi tr ny c ly t trng window trong gi d liu TCP dng xc nhn cc byte ti ni. Gi tr ny chnh l s d liu m my B c th chp nhn. My B by gi li gi mt thng bo tha nhn c ACK=3, Window=6. Lc ny d liu c dng nh di.

Hnh 31.D liu thng bo tha nhn ACK Cc byte 0, 1, 2 c xc nhn, ca s m rng ra, window limit nhn gi tr 3+6 =9. Nh vy s byte c th truyn i c iu khin bi my B, iu ny gip

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gim i s tc nghn giao thng trn mng v lm cho my B c th ch ng x l d liu n mt cch tri chy. Khi c li xy ra trn ng truyn v phi truyn li d liu th TCP khng ch i thng bo xc nhn t pha my B m n lm theo cch sau: khi truyn mt gi d liu, TCP bm gi v nu thi gian ht m khng thy thng bo xc nhn th n tin hnh truyn li. Nh vy thi gian bm gi ht sc quan trng. Ban u thi gian ny c thit lp xung quanh khong thi gian k t khi TCP A gi d liu i n khi nhn c thng bo xc nhn. Nhng v sau do cch tnh ny khng hp l nn ngi ta a ra nhiu cch thit lp khc nhau. Mt trong cc cch tnh c dng ph bin hin nay l thut ton ca Phil Karn. Ni dung cn bn ca thut ton l mi khi ht thi gian th khong thi gian bm ng h tng ln gp mt s ln cho trc. NVT=A x VT NVT: gi tr thi gian mi bm ng h A : hng s, thng ly bng 2 VT: gi tr thi gian ca 1 ln gi v xc nhn C ch kt ni gia hai my trong mng Internet Chng cui cng trong hot ng ca mng Internet l c ch kt ni gia hai my. ton b cc hot ng truyn tin gia hai my trong mng c th din ra th phi hnh thnh knh lin lc hay mt kt ni gia chng. Qu trnh din ra nh sau:

Hnh 32.Qu trnh kt ni gia 2 my trong mng 1: ULP B gi s l mt chng trnh mail server M. Do l server nn lc no n cng ch i s kt ni.CHNG 4

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2: ULP A l chng trnh nhn th in t ca bn. kt ni, bn gi yu cu kt ni xung cho tng TCP. 3: TCP chun b mt gi d liu TCP vi c SYN=1 yu cu c s ng b ho, SEQ c th ly bt k gi tr no, y l =100 v gi cho TCP B. 4: Sau khi nhn gi d liu c SYN=1, TCP B gi tr li mt thng bo c SYN=1, ACK=101, SEQ c th ly bt k gi tr no, y l =177. 5: TCP A nhn c gi d liu t TCP B s gi tip mt gi d liu c ACK=178. 6: TCP A chuyn chp nhn kt ni ln chng trnh A. 7: Sau khi nhn nt gi d liu c ACK=178, TCP B chuyn chp nhn kt ni ln chng trnh B. S kt ni gia 2 module TCP cc bc 3, 4, 5 gi l c ch bt tay 3 bc (three way handshake). Qu trnh ng mt kt ni cng thc hin tng t. 4.13 CCH M PORT CHO MODEM Thit lp NAT cho modem Internet (Thit lp ny dng cho mng FPT). u tin m trnh duyt Internet Explorer g vo Command Bar a ch : http://192.168.1.1. vo giao din qun l modem nh hnh bn di:

Hnh 33.ng nhp modem H thng s yu cu bn nhp Password. Nhp vo password l 12345 hoc 1234 (nhp 2 ln lin tip h thng s t lu password mi cho bn). Nhn chn Login

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vo giao din qun l modem nh hnh bn di. Gm cc mc bn thit lp cc thng s cho modem. Nh Network, Security, Advanced, Maintenamce.

Hnh 34.Giao din Port NAT thit lp NAT, chn th NAT ti Network > NAT > Port Forwarding. m NAT mi: Service Name: ta chon bt k ri sa li sau. Server IP Address: s IP ca my bn do moderm cp v d IP ca my ti lc ny l 192.168.1.36. Chn Add. Khi s c NAT mi trong danh sch vi tn mc nh. Ta chn edit NAT s c giao din sau:

Hnh 35.Thay i thng s Port NAT

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Lc ny ta c th chnh sa li cc thng s ca NAT. Nh Service Name, Start Port (Port m u) v End Port (Port kt thc), Server IP Address. Ch l cc Port nm trong khong gia Start Port v End Port l cc Port c php s dng. Kt thc ta chn Apply. cc thit lp NAT hot ng ta phi tin hnh tt h thng Firewall ca moderm. Bng cch tin hnh nh sau: Vo Firewall theo ng dn Security > Firewall > General nh hnh di:

Hnh 36.B chn Active Firewall B chn Active Firewall Nhc im: Mi ln reset modem th IP s i khc. Do phi vo iu chnh li. khc phc nhc im ny, ngi dng vi mc ch kinh doanh c th mua tn min c nh, kt ni socket s thng qua tn min v s khng b thay i.

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CHNG 5 THIT K PHN CNG5.1 TNG QUAN V H THNG

Hnh 37.S hot ng tng quan ca h thng Tng quan H thng gim st v iu khin t xa quan mng Internet v GSM bao gm cc thnh phn: My tnh kt ni GSM module: My tnh c ci phn mm SMSCK v kt ni vi kit iu khin v GSM module c nhim v qun l iu khin thc hin cc chc nng iu khin thit b, thc hin nhn tin v cuc gi. ng thi nhn v x l tn hiu iu khin t my tnh khc qua Socket hoc t in thoi qua tin nhn SMS thc hin cc chc nng theo yu cu. My tnh c ci phn mm SMSCK: Thng qua mng Internet (LAN) ta c th kt ni t bt k my tnh no c ci phn mm SMSCK vi my tnh ch c kt ni vi kit iu khin v GSM module v thc hin vic iu khin gin tip qua Socket. in thoi: L bt k chic in thoi no c chc nng nhn tin SMS. Bng vic gi tin nhn theo cu trc nh sn do module qui nh. Ngi iu khin c th qun l v iu khin cc thit b t bt c u trong vng ph sng ca mng in thoi h tr.

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5.2 S KHI CA GSM MODULE

BTS KHI IU KHIN V GIAO TIP KHI GSM Modem SIM300CZ

USB

USART

PC

Hnh 38.S khi GSM module KHI IU KHIN V GIAO TIP S dng chp iu khin ARM STM32F103 ca hng STMicroelectronic. Thc hin vic iu khin cc thit b v m nhn vic giao tip gia Module GSM v my tnh. Khi ny s nhn d liu t my tnh thng qua giao tip USB sau x l d liu thc hin yu cu, nu l tn hiu iu khin thit b khi ny s thc hin vic iu khin thit b qua cc cng I/O. Nu l tn hiu iu khin t Module GSM th khi s x l v a ra lnh AT tng ng iu khin Module GSM qua cng USART, v nhn phn hi t Module GSM thc hin yu cu iu khin thit b hoc gi ln my tnh. KHI GSM Modem SIM300CZ Khi s dng module SIM300CZ ca hng SIMCom. Khi thc hin chc nng giao tip vi mng in thoi di ng v mng di ng nhm thc hin s dng l mng Viettel. Module GSM ny s thc hin vic nhn v gi tin nhn SMS, nhn cuc gi n v pht sinh cuc gi i. V chc nng kt ni GPRS giao tip vi mng Internet qua giao thc TCP/IP vi ti ca nhm chc nng ny ca module cha c s dng. V Module GSM c lnh AT t KHI IU KHIN v GIAO TIP qua giao tip USART hot ng.

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5.3 KHI IU KHIN V GIAO TIP 5.3.1 S KHIModule GSM PCMAX 232USART

Thit bI/O

CHIP ARM STM32F103

USB

PC

NGUN 5V IC7805

NGUN 3.3V IC1117

Hnh 39.S khi ca mch iu khin v giao tip 5.3.2 CHIP ARM STM32F103

Hnh 40.Chip ARM Cortex M3 Ngy nay cc nh sn xut IC a ra th trng hn 240 dong chip vi iu khin s dng li ARM. Th tp on ST Microelectronic th cho ra mt dng chip STM32, vi iu khin u tin da trn nn li ARM Cortex M3 th h mi do hng ARM thit k, c ci tin t li ARM7 truyn thng, tng mang li thnh cng vang di cho cng ty ARM. Dng STM32 thit lp cc tiu chun mi v hiu sut, chi ph, cng nh kh nng p ng cc ng dng tiu th nng lng thp v tnh iu khin thi gian thc khc khe. Khng gian a ch 4Gbyte ca Cortex M3 c chia l cc vng cho b nh chng trnh, SRAM, ngoi vi v ngoi vi h thng. Cortex M3 c thit k da theo cu trc Harvard (b nh chng trnh v b nh d liu tch bit nhau). C nhiu bus c th thc hin nhiu cng vic song song vi nhau, do l tng hiu sut chip. Khng ging nh cc dng ARM trc y, dng Cortex cho php truy cp b nh khng xp hng (v dng ARM c kin trc 32 bit, do tt c d liu v m chng trnh sp xp theo bi s ca 4byte) nn c im ny cho php s dng hiu quCHNG 5

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SRAM ni. Dng Cortex cn h tr vic t v xa cc bit bn trong hai vng 1Mbyte ca b nh bng phng php gi l bit banding. c im ny cho php truy cp hiu qu n cc thanh ghi ngoi vi v cc c c dng trn b nh SRAM m khng cn mt b x l lun l. Mt trong nhng thnh phn chnh ca li Cortex M3 l NVIC (Nested Vector Interrupt Controller). NVIC cung cp mt cu trc ngt chun cho tc c cc vi iu khin c thit k trn li Cortex v cch x l ngt c bit (exceptional interrupt). NVIC cung cp cc vector ngt chuyn dng ln n 240 ngun ngt t ngoi vi, mi ngun ngt c th c u tin vi cc mc khc nhau. NVIC c thit k x l cc ngt i hi thi gian p ng cc k nhanh. Thi gian t lc nhn tn hiu ngt cho ti khi thc hin dng lnh u tin trong trnh phc ngt ch khong 12 chu k xung nhp. Cng vic ny c thc hin t ng bi mt vi chng trnh ci sn trong CPU. Trng hp cc ngt lng nhau NVIC s dng phng thc gi l tail chain cho php ngt lin tip c phc v vi tr ch c 6 chu k xung nhp. Trong qu trnh thc thi chng trnh phc v ngt, mt ngt c mc u tin cao hn ngt hin ti c th cnh tranh vi ngt hin ti m khng chu bt k s tr hon no. c im ni bt ca STM32 so vi cc dng ARM khc chnh l kh nng truy cp b nh khng xp hng (Unaligned Memory Accesses). Tp lnh ARM7 v ARM9 c kh nng truy cp cc bin c du v khng du c kch thc byte, half word (thng l 2 byte) v word (4byte) . iu ny cho php CPU h tr cc bin s nguyn m khng cn n th vin phn mm h tr, thng c yu cu vi vi iu khin 8bit v 16bit. Tuy nhin, cc phin bn CPU ARM trc gp bt li ch, n ch c th truy cp d liu c kch thc l word hay half word. iu ny hn ch kh nng ca lin kt ca trnh bin dch (compiler linker) trong vic ng gi d liu vo SRAM, nh vy mt s SRAM s b lng ph. Vic lng ph ny c th ln n 25% ty thuc vo s kt hp ca cc bin c s dng. B x l Cortex M3 c th truy cp b nh khn