Hình ảnh chuẩn H323.doc

Hình ảnh chuẩn H323

Network

Data link

Physical

H2:H.323 Protocols in relation to the OSI model

G.711

G.722

G.728

G.729 G.723.1.1

Presentation

T.127

T.126

T.124

T.125/T.1222

H.450.1

H.450.3 H.450.2

X.244.0

H.235

UDB

TCP

Audio signal Application

Video signal

Data signal

Transport

supplementary Services

Control

zone 1 zone 2

H×nh 3: kiÕn tróc t¹i Terminal H.323 cña Cisco

Video Conference Architecture

a typical H.323 Terminal

Video I/O

Equipment

Audio I/O

Equipment

User Data

Applications

System

Control

User

Interface

H.225.0 Layer

Locall Area Network Intererface

recovery Path Delay

Video codec H261, H263

Audio condec G711, G722, G723, G728 G729

System control

1 Setup

2 Alerting

3 Connect

4 TermCapSet

5 TermCapAck

6 mSDet

7 mSDetAck

8 mSDetConfirm

9 openReq

10 openAck

11 endSession

12.ReleaseComplet

Q.931 messages

H.245 messages

1

4

A 5

6

8

9

10

11

12

H245 control

Call control H226.0 RAS Control

zone 1 zone 2

yes you can! H×nh4: Admission - Cisco Admission Control With Cisco IOS MCM Gatekeeper – Call Across WAN IP WAN Admission Control Via Zone BandWidth in the Cisco IOS MCM Gatepeer May I call 2111 with a bandwidth of 384K? 1 Setup 2 Alerting 3 Connect 4 TermCapSet 5 TermCapAck 6 mSDet 7 mSDetAck 8 mSDetConfirm 9 openReq 10 openAck 11 endSession 12.ReleaseComplet Q.931 messages H.245 messages 1

4

A 5

6

8

9

10

11

12

Call flow H.323 RAS signaling

hình 6:Trao đổi thông điệp Q.931 Và H.245 giữa hai H.323 Terminal

1 Setup

2 Alerting

3 Connect

4 TermCapSet

5 TermCapAck

6 mSDet

7 mSDetAck

8 mSDetConfirm

9 openReq

10 openAck

11 endSession 12.ReleaseComplet

Q.931 messages

H.245 messages

1

4

A 5

6

8

9

10

11

12

2 3

5

4 B

7

10 9

11