Cp si quang hon ton cch in, khng chu nh hng ca sm st, khng b can nhiu bi trng in t, xuyn m gia cc si quang khng ng k

phn cng SM v phn mm MLH thng tng i Alcatel 1000E10 hay Alcatel 1000E10 MM c chia ra lm 2 phn h chnh l: phn h truy nhp thu bao v phn h chuyn mch OCB.

Phn h truy nhp thu bao gm c cc khi tp trung thu bao gn CSNL v khi tp trung thu bao xa CSNDphn h chuyn mch OCB: quan ly cac SM(SMC, SMA, SMM, SMT, SMX) bang phan mem mlkhi tp trung thu bao CSN. Khi truy nhp thu bao CSN (Subscriber Access Unit). Khi truy nhp thu bao CSN l n v u ni trc tip n thu bao, c kh nng phc v ng thi cho c thu bao tng t ln thu bao s. CSN c thit k theo 2 kiu: ni ht (CSNLCSN Local) hoc v tinh (CSNDCSN Distance) ph thuc vo v tr lp t CSN so vi tng i. CSND c cp ngun ring cn CSNL s dng chung ngun vi tng i trung tm. Mi CSN u c 2 t Accu (cp ngun 48 VDC) lun c np d phng trong trng hp mt in li.

ADM

Add/Drop Multiplexer :

Cp si quang hon ton cch in, khng chu nh hng ca sm st, khng b can nhiu bi trng in t, xuyn m gia cc si quang khng ng k. Vt liu ch to l SiO2 sn c trong t nhin nn gi thnh thp.

Suy hao truyn dn nh.

Bng tn truyn dn ln.

Khng b nh hng ca nhiu in t.

C tnh bo mt thng tin cao.

Kch thc v trng lng nh.

tin cy cao v linh hot.

Cc tn hiu quang ny c khuch i vi cng sut ln a vo mi trng truyn dn l cp si quang

cc trm lp b li cng sut b suy gim

Mt c im quan trng ca si quang l rng bng tn, cp si quang c th truyn tn hiu vi tn s cao hn rt nhiu so vi cp kim loi v cp ng trc

Trong cc tuyn thng tin quang im ni im thng thng, mi mt si quang s c mt ngun pht quang pha pht v mt tch sng quang pha thu

Nh vy mun tng dung lng h thng th phi s dng thm si quang. K thut ghp bc sng quang s cho php ta tng dung lng knh m khng cn tng tc bit ng truyn v cng khng cn dng thm si dn quang

So vi cng ngh truyn dn n knh truyn thng, cng ngh WDM c u im ni tri nht l tng dung lng truyn dn trn mi si quang ln rt ln nh tng s knh bc sng trn mi si quang

. Hin nay, mng ng trc ca Vit Nam do Cng ty Vin thng lin tnh ch tr s dng 8 knh bc sng, dung lng ca mi knh l 10Gbps, nh vy tng dung lng l 80Gbps. Tuy nhin, h thng ny cho php s dng ti a 32 knh bc sng v tc ca mi knh c th ln hn. Ngoi ra, vi cc h thng khc, s knh bc sng c th s dng l 64, 128 hoc ln hn. Cng ngh WDM cng c th trin khai hoc nng cp h thng trn c s mng quang hin c, gim chi ph u t.

1.3.4. Cu hnh vng

Cu hnh vng (ring) bao gm ti thiu ba nt ADM kt ni vi nhau bi mt cp si quang to thnh mt vng kn nh hnh 1.6. V vy cu hnh ny cn gi l cu hnh kn phn bit vi cu hnh h trnh by trn y.

Hnh 1.6. Cu hnh mng Ring

Cu hnh vng (Ring) c kt ni vi nhau qua 2 si hoc 4 si quang. Cu hnh vng c kh nng duy tr mng (hay cn gi l t phc hi) khi t cp ti mt im bt k hoc hng mt ADM bt k bng cch chuyn mch bo v.

1.3.5. Cu hnh a vng

C th kt ni nhiu vng vi nhau qua cc ADM hoc qua nt ni cho s to thnh mng a vng (hnh 1.7). Cu hnh ny c s dng nhiu trong thc t, bi v p ng c nhu cu pht trin cc dch v vin thng trn mt vng a l rng ln khng ch bao gm mt quc gia m nhiu quc gia.

Hnh 1.7. Cu hnh mng a vng

Mng a vng c kh nng t phc hi trong trng hp trn mi vng cp b t ti mt im bt k hoc hng mt nt, tr nt kt ni hai vng.

Cu trc Token Ring : (tiu chun IEEE 802.5 ) c th chy tc 4Mbps hoc 16Mbps. Phng php truy cp dng trong mng Token Ring gi l Token passing. Token passing l phng php truy nhp xc nh, trong cc xung t c ngn nga bng cch mi thi im ch mt trm c th c truyn tn hiu. iu ny c thc hin bng vic truyn mt b tn hiu c bit gi l Token (m thng bo) xoay vng t trm ny qua trm khc. Mt trm ch c th gi i b d liu khi n nhn c m khng bn. Khi trm A mun gi mt bn tin n trm C th n phi thc hin nhim v l nu trm A chim Token Ring th phi chuyn Token thnh bn, cn trm A gi bn tin ca n n trm B chuyn ti trm C v trm C cng nhn a ch ca trm A, sao chp tin tc v gi cng nhn v trm A. Cn v pha trm A n c nhim v nhn bit tn hiu cng nhn, xo thng tin (nu tr li t trm C l ng) v chuyn Token thnh ri.

Mng NGN l mng g ? mng th h mi : hp nht tt c cc dch v bng rng, bng hp, di ng, c nh TCP/IP m bo kt ni u cui v cung cp kh nng nh tuyn linh hot, ATM cung cp a dch v bng rng v STM h tr truyn dn tc cao. (Hi t mng, hi t dch v, hi t ng dng)

Mng truyn dn gm 2 loi, mng viba v mng quang. Mng viba dng cho cu hnh im im, v c s dng cho cc a hnh him tr kh trin khai mng c dy. Mng quang ti Vin Thng TT Hu ch yu l xy dng theo cu trc mng vng (ring). ). Mng dng ny, b tr theo dng xoay vng, ng dy cp c thit k lm thnh mt vng khp kn, tn hiu chy quanh theo mt chiu no . Cc nt truyn tn hiu cho nhau mi thi im ch c mt nt m thi. D liu truyn i phi c km theo a ch c th ca mi trm tip nhn. Mng dng vng c thun li l c th ni rng ra xa, tng ng dy cn thit t hn so vi dng bus v hnh saotng i E10MM

im truy nhp cho mng bng rng: Tng i A1000 E10 MM c kh nng kt ni mng bng rng, s dng thoi qua ATM (VoATM), h tr d liu theo nguyn l ng dy thu bao bt i xng tc cao ADSL (Asymmetric Digital Subscriber Line) vi tc chiu ln 640kbit/s v chiu xung 6Mbit/s ti b truy cp thu bao s a dch v (CSN MM)

Ch vi duy nht 1 tng i E10MM c th m nhim c nhiu chc nng chuyn mch v nh tuyn cho cc dch v c nh hay di ng, ni ht, qu giang v quc t. Cung cp 1 gii php pht trin ln mng NGN vi cc cng ngh IP/ATM.

* Mt s tnh c trng ca h thng tng i ny l:

Multiservice: 1 thit b c tch hp nhiu tnh nng, ng thi c th s dng lm tng i c nh hoc di ng, ni ht hoc transit.

Hot ng theo Modul nn d dng thay i kh nng, tnh nng.

Tnh tng thch ca phn cng v phn mm pht trin c lp nhau. iu ny m bo tnh tng thch ca thit b khi nh khai thc yu cu nng cp tng i. V d: nng cp phn mm t R22 ln R24, nng cp phn cng t E10 ln E10MM.

* Do ni tri ln nhng c tnh ni bt nh :

Cht lng dch v (QoS) khng ph thuc vo kiu ca mng truyn ti: cht lng dch v thoi qua chuyn mch knh (PSTN) hoc chuyn mch gi l nh nhau.

Bo m dch v cng thm trong tng i bo tn ngun thu nhp, nng cao hiu qu kinh t bi cc dch v trn mng PSTN/ISDN ca nh khai thc..

Kh nng pht trin dch v da trn cng ngh gi trong tng lai: VoATM, bin i m UMTS.

H tr vic tnh cc thng qua vic to ra cc bn ghi cc cho bt c 1 hnh thc thng tin no.

Kh nng tng thch kt ni vi tt c thit b Vin thng hin c trn mng, m bo s tng tc gia cc mng s liu quc gia v quc t.

Cung cp cc kt cui mng tch hp dung lng cao nh SDH STM1.

H thng tng i A1000 E10 bao gm 3 phn h chc nng c lp:

Phn h truy nhp thu bao: u ni cc ng dy thu bao tng t, s....

Phn h iu khin v u ni: c nhim v qun l chuyn mch knh phn chia theo thi gian v cc chc nng x l cuc gi, tnh cc,...

Phn h qun l, khai thc v bo dng: l phn giao tip gia k thut vin vn hnh v h thng tng i Host (giao tip ngi my). N qun tr cc kt ni vo h thng tng i m qua ngi iu hnh h thng c th nhp lnh, tc ng vo h thng; ngc li h thng s a cc thng tin v cc p ng ra cc thit b hin th v lu tr. Qua h thng c vn hnh, khai thc v bo dng mt cch ph hp.

Cc phn h ny c hnh thnh da trn cc trm SM v cc khi tp trung thu bao CSN.

Cc trm SM bao gm:

SMC : Trm iu khin chnh. SMA: Trm iu khin thit b ph tr. SMT : Trm iu khin trung k. SMX : Trm iu khin ma trn chuyn mch. SMM : Trm khai thc v bo dng

Cc khi tp trung thu bao CSN bao gm:

CSNL: khi tp trung thu bao gn

CSND: khi tp trung thu bao xa

Ngoi ra, h thng A1000 E10 cn c mt khi STS l khi to tn hiu nh thi, tip nhn tn hiu ng b ngoi trn mng. V c mt vng cnh bo MAL lin kt cc khung, cc trm thu thp v a thng tin cnh bo ca cc thit b v trm SMM x l v a thng tin cnh bo ra thit b hin th.

Cc trm SM ca h thng c lin kt vi nhau bi cc mch vng thng tin Token Ring, l cc mch vng MIS v MAS. Mch vng MIS to lin kt gia trm SMC v SMM, cn mch vng MAS to lin kt gia cc trm SMC, SMX, SMA v SMT.

II.4. Cc phn h ca h thng chuyn mch tng i A 1000E10 MM

H thng tng i Alcatel 1000E10 hay Alcatel 1000E10 MM c chia ra lm 2 phn h chnh l: phn h truy nhp thu bao v phn h chuyn mch OCB.

Phn h truy nhp thu bao gm c cc khi tp trung thu bao gn CSNL v khi tp trung thu bao xa CSND.

Phn h chuyn mch OCB trong h thng A1000E10 c 2 th h l:

OCB 181

OCB 283

Cn phn h chuyn mch OCB trong h thng A1000E10 MM c cc th h sau:

OCB 283

OCB HC2

OCB HC3.x. Th h OCB HC3 li c chia thnh cc phin bn:

OCB HC3.1

OCB HC3.3

OCB HC3.4

Hnh 5: Cu trc phn cng ca tng i A1000 E10

Hnh 6: Cu trc phn mm ca tng i A1000 E10

Hnh 11: Cu hnh h thng A 1000E10 MM

Trong hnh v tren y ta thy r s thay i cu trc h thng trong tng i A 1000E10 MM so vi A 1000E10.

Ta thy trong h thng A 1000E10 MM, cc mch vng thng tin MIS v MAS c thay th bng 1 mch vng thng tin OCB LAN ni cc trm vi nhau. Trng chuyn mch RCX c thay th bng trng chuyn mch RCH. Mt s trm chc nng c thay th bng cc trm SMB a nng

Giao thc bo hiu s 7 hay cn gi l SS7, l cm t vit tt ca Signaling System # 7, l tp hp cc giao thc in thoi c s dng thit lp hu ht cc cuc gi trong mng PSTN. V sau c pht trin thm cc giao thc, thnh phn mi h tr bo hiu cho cc mng khc nh mng di ng mt t PLMN, mng s tch hp a dch v ISDN.

Chc nng chnh ca SS7 l thit lp cuc gi, kt thc cuc gi, chuyn i s, tnh cc, SMS.

Khi nim v bo hiu Bo hiu l s trao i thng tin gia cc thnh phn trong mng in thoi vi nhau. Cc thng tin ny c chuyn ti di dng cc bn tin.

[sa] Phn loi bo hiuCc phng php bo hiu c phn bit theo cc tiu ch sau:

Loi tn hiu bo hiu:

- Bo hiu Analog (nh DC, 1VF, 2VF, MF).

- Bo hiu Digital (nh CAS, DSS1, SS7).

Thng tin bo hiu:

- Bo hiu ng dy thu bao (user - net).

- Bo hiu ng trung k (net - net).

- Bo hiu qua mng (user - user).

Ch bo hiu:

- Bo hiu la chn.

- Bo hiu ng.

Chiu bo hiu:

- Bo hiu hng thun (call - called).

- Bo hiu hng ngc (called - call).

Phng thc bo hiu:

- Bo hiu knh kt hp (CAS).

- Bo hiu knh chung (CCS).

Cc loi bo hiu s dng cho Tng i:

Signaling Type[sa] Tng quan mng bo hiu[sa] Lch s ra i cc mng bo hiu T nm 1975, cc giao thc bo hiu knh chung c pht trin bi t chc quc t ITU-T v nhiu cng ty ln trn th gii. H thng bo hiu u tin c ITU-T nh ngha vo nm 1977 c tn gi l SS6.

H thng SS7 c nh ngha bi ITU-T vo nhng nm 1980. Cc khuyn ngh dnh ring cho SS7 l Q.7xx.

[sa] Cc h thng bo hiu[sa] H thng bo hiu s 7[sa] Lch s ra i Vo u nhng nm 80 ca th k 20, t chc tiu chun vin thng quc t ITU-T a ra cc khuyn ngh v h thng bo hiu s 7 (k hiu SS7). H thng SS7 l h thng bo hiu knh chung c thit k dnh ring cho mng vin thng s.

[sa] Cc phn t bo hiu ca SS7H thng SS7 gm 4 thnh phn chnh: im chuyn mch dch v - SSP (Service Switching Point); im trung chuyn bo hiu - STP (Signaling Transfer Point); im iu khin bo hiu - SCP (Service Control Point) v Link SS7.

SS7 Components SSP - im chuyn mch dch v:

- SSP l cc b no ca mng SS7 v c t ti cc chuyn mch. - Chc nng ca SSP l x l cc cuc gi khi xng (Originating Call), qu giang (Transit Call) hoc kt cui (Terminating Call) bng cch to cc bn tin bo hiu gi thng tin lin quan ti cuc gi ti cc SSP khc, hoc gi truy vn ti c s d liu SCP thc thi vic nh tuyn cuc gi.

STP - im trung chuyn bo hiu:

- Chc nng chnh ca STP l chuyn tip cc bn tin bo hiu (hay chc nng nh tuyn bo hiu). - STP l mt b chuyn mch gi hot ng nh mt hub gi cc bn tin bo hiu ti cc STP, SCP hay SSP khc. - STP nh tuyn cc bn tin thng qua vic kim tra thng tin nh tuyn c gn km vi mi bn tin bo hiu v gi chng ti im bo hiu cn thit.

SCP - im iu khin dch v:

SCP l mt mt tp hp cc c s d liu lu gi thng tin cn thit cung cp cc dch v phc tp hn so vi iu khin cuc gi c bn (v d cung cp dch v gia tng, cc dch v tng i 1800).

Cc loi Link SS7: Cc Link SS7 gm cc loi: A, B, C, D, E, F...

SS7 Link Kt ni cc thnh phn trong mng bo hiu:

SS71[sa] Cu trc h thng SS7H thng SS7 c cu trc theo dng M-un v ging vi m hnh tham chiu OSI nhng ch c 4 lp: 3 lp thp 1, 2, 3 to thnh phn chuyn giao tin bo MTP. Lp 4 cha cc thnh phn UP (User Protocol) cho ngi dng. Mt s thnh phn UP cho cc ngi dng khc nhau nh sau:

TUP (Telephony User Protocol) - Phn ca user dng in thoi.

DUP (Data User Protocol) - Phn ca user dng s liu.

ISUP (ISDN User Protocol) - Phn ca user dng ISDN.

MTUP (Mobile Telephony User Protocol) - Phn ca user dng di ng.II.5.6. Khi truy nhp thu bao CSN (Subscriber Access Unit)

Khi truy nhp thu bao CSN l n v u ni trc tip n thu bao, c kh nng phc v ng thi cho c thu bao tng t ln thu bao s. CSN c thit k theo 2 kiu: ni ht (CSNLCSN Local) hoc v tinh (CSNDCSN Distance) ph thuc vo v tr lp t CSN so vi tng i. CSND c cp ngun ring cn CSNL s dng chung ngun vi tng i trung tm. Mi CSN u c 2 t Accu (cp ngun 48 VDC) lun c np d phng trong trng hp mt in li.

C th cung cp c nhiu loi ng dy thu bao khc nhau nh: thu bao analog truyn thng, thu bao ISDN, V5.1, leased lines 64kbps, thu bao ADSL. Tt c cc loi thu bao u c s dng cc thit b tch hp ring loi board mch khc nhau, Plug to plug tng thch.

Hnh 18: Ti u ho CSN

Gii php tng hp c ADSL lm linh hot cho vic iu hnh, kh nng ng dng Multimedia, tit kim chi ph u t DSLAM, tit kim trong chi ph thit b, linh kin thay th v kinh ph o to. Tnh linh hot tr nn cc i.

Hnh 19: Tch hp ADSL vo Tng i

Trong vic vn hnh bo dng th s dng chung 1 quy tc v th tc, khng c nguy c xung t gia nhng h thng qun l khc nhau

Gii php tch hp ADSL gip gim gi thnh nhiu loi chi ph (thit b, k hoch u t, ) tr nn ph hp vi thc tin mng Vin Thng hin i Multiservices. Tc ADSL tiu chun 8Mbps/640kbps

Kh nng giao tip STM1 cung cp ADSL kt ni vi BRAS bng card TCTB1 ca CSNMMMt CSN c chia thnh 2 phn:

n v iu khin s UCN gm: n v iu khin u ni UCX v nhm x l thit b ph tr GTA.

B tp trung s CN gm: CN ni ht (CNL) v CN v tinh (CNE).

GTA c trang b cc b thu tn s, pht tn hiu m thanh, thu ting ni, phn nhm cnh bo thc hin mt s chc nng:

To tone v cc bn tin thng bo phc v cho thng tin ni b nu CSN trng thi c lp.

Nhn bit cc tn hiu a tn t cc my n phm nu CSN trng thi c lp.

o kim cc ng thu bao u ni vi cc CNL.

Trong mt CSN s c hai UCX hot ng theo ch d phng Active/Stanby. Mi UCX li gm 2 phn: mng u ni RCX v n v iu khin UC. Nh vy, mi CSN ni chung gm c 4 thnh phn: RCX, UC, GTA v CN.

Mt CSN qun l ti a 20 CN, mt CN c ti a 16 Card thu bao thng (TABASE) hoc thu bao o cc (TABAF), mi Card thu bao c 16 thu bao. V vy, s lng thu bao ti a trong mt CSN l 5120 thu bao. CNL ni n RCX bng cc ng LRI (ng LR ni b) chy theo giao thc HDLC. Mi CNL ni vi RCX t 2 n 4 ng LRI. CSNL c u ni trc tip vi chuyn mch trung tm bng t 2 n 16 ng LR, cn CSND th s dng t 2 n 16 lung PCM thng qua trm iu khin trung k SMT2G. C 2 loi CSND ny u giao tip vi chuyn mch trung tm bng bo hiu s 7 ni b trn khe 16 ca 2 ng kt ni u tin.

Cc CSN c nh s trong trng chuyn mch RCH t 1 n 63. T 64 n 223 dnh cho SMT2G, 224 v 225 dnh cho GTA. C ti a 48 ng LR ni n RCX c phn b nh sau:

LR0 n LR2 dng cho bo hiu HDLC v SS7 ni b.

LR3 v LR4 dng cho GTA.

LR5 d phng.

LR6 n LR47 dng cho cc CSN.

Nhn chung, CSNL v CSND c cu trc hon ton ging nhau nhng CSND c thm mt s thit b m CSND khng c, hu ht l cc thit b phc v cho CSND khi t n hot ng trng thi c lp (ch t tr).II.5.7. Trm vn hnh bo dng SML

Trm SML l trm iu khin n da trn h iu hnh Linux v truyn thng IP. N c s dng vn hnh, bo dng h thng tng i A 1000E10 MM vi cu hnh HC s dng mch vng thng tin Ethernet (SSETH). Mi mt phn h x l ca trm SML ch nm trn 1 card. Card ny gm c a cng ca phn h x l v khi ng b v c s thi gian STS2G. Mi card ny gm c:

- Hai cng Ethernet ni ti 2 switch truy nhp ti mng Ethernet o (SMTR, MNGI v BOOT).

- Mt cng Ethernet lin kt 2 nhnh x l SMLA v SMLB ca trm SML.

- Mt cng ni tip ni ti giao din h tr iu khin qua ng kt ni RS232.

II.5.8. Mch vng thng tin Ethernet LAN

Hnh 20: Mch vng thng tin LAN

Mng LAN bao gm:

- 2, 4 hoc 8 token ring

+ 16 Mbps mi vng

+ c nhm thnh cp

+ hi thoi gia cc chc nng khc nhau

+ ph hp vi IEEE 802.5

- 2 ng bus Ethernet 10 Mbps: giao din truyn thng gia chuyn mch v my ch

c tnh:

- Tc 100 Mbps

- C cu trc mng IP m

Mch vng ny truyn thng tin iu khin gia cc trm, cc terminal khia thc, bo dng v cc router truy nhp vo mng IP. N bao gm 3 mng o, l:

- Mng o SMTR: mng ring ni b trao i thng tin iu khin gia cc trm SML v cc trm SMB

- Mng o MNGT: mng ring m to ra lin kt thng tin gia cc trm SML, khi pht m thng bo th h 2 (MPNA2) v terminal qun l:

Terminal ti ch (OMT, OOT, AMT)

Terminal t xa (NMC2, CDRC, A1330) thng qua mng IP m bo

Vi A 1000 E10 MM trong mi trng NGN, mng MNGT cn c dng trao i thng tin gia:

Cc trm SMB c chc nng ML MGI vi cc MG

Cc trm SMB c chc nng ML PUPE vi my ch SIP.

- Mng o BOOT: mng ring ni b gia cc trm SML, terminal OMT v cc trm SMB nh tuyn cc thng tin BOOTP/DHCP/TFTP. Mng ny ch c s dng khi khi to cc trm. Vic trao i thng tin trn mng ny theo c ch ch t, trong ln khi to u tin.Chng 3: THIT LP, X L CUC GI GIA HAI THU BAO

Sau y l qu trnh thit lp cuc gi gia hai thu bao ni b trong Tng i E10. Thu bao ch gi l t CSND A v thu bao b gi l trong CSND B. Cc bc xy ra nh sau:

Hnh 21: Cuc gi gia 2 thu bao A v B

III.1. Thu bao ch gi nhc my

Khi thu bao ch gi nhc my, CSND A s gi bn tin NOVAP v tnh trng nhc my ca ca thu bao thng qua ng COC/ PCM/ SMT n PUPE (bn tin ny s cha s ca thu bao ch gi), PUPE gi bn tin OUNAP n cho MR. Lc ny, mt khe thi gian dnh sn trn ng PCM gia CSND A v Tng i E10.

III.2. Kim tra loi ca thu bao ch gi

Sau khi nhn c bn tin OUNAP, MR s gi bn tin n TR yu cu xem xt loi ca thu bao ny. TR s tra cu d liu ca n v sau gi bn tin tr li v cho MR thng thng bo rng thu bao ny c php xut pht cuc gi.

III.3. Kt ni m hiu mi quay s v chp nhn cuc gi

Thng qua ng LAN, MR gi bn tin DCXIAN ti cho COM yu cu kt ni m hiu mi quay s. m hiu mi quay s ny c to ra bi GTA, khe thi gian dnh cho cuc gi d nh thit lp trn ng PCM ni gia CSND A v Tng i E10 s c kt ni ti GTA, tc l lc ny thu bao s nhn c m hiu mi quay s.

III.4. Nhn con s quay u tin

Lc ny thu bao ch gi thc hin qu trnh quay s. Khi nhn c con s u tin, CSND A s gi bn tin CHUN v cho Tng i E10 yu cu ct m hiu mi quay s. Lc ny MR s gi bn tin ti cho MQ v MQ ra lnh cho COM ct m hiu mi quay s v cho thu bao ch gi. Lc ny thu bao ch gi tip tc quay con s tip theo, mi con s quay u c CSND A gi trn ng COC v cho MR. Sau khi nhn cc con s, MR bit c a ch ca thu bao bng cch gi bn tin DTRAD km theo cc con s xong th s gi bn tin tr li RTRAR.

III.5. Kim tra trng thi thu bao b gi

Sau khi bit c chnh xc a ch ca thu bao b gi CSND_B, MR s gi bn tin ti cho PU/PE v thng qua ng COC gi bn tin ti cho CSND_B hi tnh trng ca thu bao B. Thu bao B ang trng thi ri, CSND_B s gi bn tin tr li v tnh trng ca thu bao B v ng thi gi dng chng n cho thu bao b gi. Mt khe thi gian ri s c cp pht trn ng PCM gia Tng i E10 v CSND_B.

III.6. Gi hi m chung (Ringing Tone) n thu bao ch gi v ch thu bao b gi nhc my

Khi nhn c bn tin tr li t CSND_B, MR ra lnh cho COM bng bn tin DCX Tone yu cu kt ni hi m chung n thu bao ch gi t ETA ca SMA.

MR sau s ch 1 trong 3 tnh hung sau:

Thu bao b gi nhc my.

Thu bao ch gi gc my.

Vt qu thi gian rung chung.

III.7 .Thu bao b gi nhc my

Khi thu bao b gi nhc my, tnh trng ny s c nhn bit bi UT ca CSND_B. Sau ng dy thu bao b gi s c ngt khi b to dng chung.

UCN gi mt bn tin EVABO (tnh trng nhc my ca thu bao b gi) v MR. Khi nhn c bn tin ny MR x gi bn tin DCXIAN n phn mm COM ca ma trn chuyn mch SMX ct tn hiu hi m chung.

III.8. Kt ni thu bao gi v b gi

MR gi bn tin DCX n cho MR hi xem hin nay GX c tip nhn thng tin hay khng, tc l GX c kh nng cp pht mt ng ni qua mng chuyn mch hay khng. GX gi bn tin chp nhn v cho MQ, MQ gi bn tin tr li cho MR v tnh trng tip thng tt. Lc ny GX s gi lnh ti cho COM yu cu kt ni hai khe thi gian dnh sn trn hai ung PCM ni ti hai CSND ch gi v b gi, tc l hai thu bao c ni vi nhau.

Lc ny MR gi bn tin ti cho TX yu cu tnh cc cho cuc gi ny. TX sau khi nhn c bn tin th s gi bn tin tr li l bt u tnh cc.

III.9. Gii phng

Khi mt trong hai thu bao gc my, bn tin gc my s c CSND gi v cho MR, MR s ra lnh cho MQ ngt ng ni gia hai thu bao qua ma trn chuyn mch v kt ni thu bao cn li ti ETA nhn m hiu bn, ng thi MR s gi bn tin yu cu ngng tnh cc ti cho TX.

++++++++++++++++++++++++++++++++++++++STM-1 (Synchronous Transport Module level-1 (M un Vn chuyn ng b mc-1) is the SDH ITU-T fiber optic network transmission standard. N c mt tc truyn theo bit la 155.52 Mbit/s.. (Higher levels go up by a factor of 4 at a time: the other currently supported levels are STM-4, STM-16, STM-64 and STM-256 ). Nhng mc Bc cao ln bi mt nhn t (h s) ca 4 ti mt thi im (K) khc hin thi h tr nhng mc STM-4, STM-16, STM-64 and STM-256. Bn ngoi iu ny chng ti c b a hp, (s) a l ha, (s) dn knh b phn bc sng (WDM) thng s dng trong tu ngm bng dy cp.[1][ 2]

Khung STM-1 l khun dng truyn c bn (cho) SDH (s Phn cp S ng b). Mt khung STM-1 c Mt cu trc hng byte vi 9 hng v 270 ct of bytes, Mt tng ca) 2,430 bytes ( 9 hng* 270 ct= 2430 bytes). Mi bytes tng ng ti mt 64 kbit/s channel.___________________________________

Mch vng thng tin

GX

MR

MQ

TX

TR

PC

OM

TMN

Alarms

URM

CSND

CSNL

Ma trn chuyn mch chnh

COM

BT

ETA

PUPE

LR

LR

LR

SN

SU2A

L

S

N

SMB_A

PUPE

ETA

AN

SMM OM &OC

SMT2G URM

OCB LAN

SMB_ACTX

TX TR MQ GX PC MR CC GS

SMB_THD URM

STS BT

SMB_X COM

RCH