voip, pstn,

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2553 1

VOIP

(VoIP) (Voice over Internet Protocol) ( IP Telephony, Internet telephony, Digital Phone)

- SIP Internet Protocol

1.

2.

Soft Switch!

.. (PSTN : Public-Switched Telephone Network ) oriented switching (Soft switch network) 1

1

3

1. Media Gateway Controller (MGC) PSTN, IP H.323,SIP,MGCP,SS7

2. Signaling Gateway (SG) SS7 PSTN IP

3. Media Gateway (MG) ,,, PSTN IP

2 Gateway

2 Gateway IP (Internet Protocol) VoIP (Voice over Internet Protocol) IP Phone H.323, SIP

PSTN (Public-Switched Telephone Network) POT Signaling SS7 (Signaling System 7)

1. (Proprietary) 2. 3.

5 ()

1. (Sender) (Message)

2. (Receiver)

3. (Medium)

4. (Message)

(Information) 5

4.1 (Text)

4.2 (Number)

4.3 (Images)

4.4 (Audio)

4.5 (Video)

5. (Protocol)

X.25, SDLC, HDLC, TCP/IP

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