0aa000007 Sip Protocol Issue2.0

ISSUEISSUE

Fixed Network Curriculum

Development Section

Fixed Network Curriculum

Development Section

OAA000007 Call controlprotocol – SIP protocolOAA000007 Call controlprotocol – SIP protocol

2.02.0

Confidential Information of Huawei. No Spreading without Permission.

Security Level: Internal

2

ObjectiveObjective

Functions of SIP protocol

SIP commands

Meanings and usage of the parameters in

SIP commands

Message interaction process of SIP

After this session, you will learn:



3

ReferencesReferences

Product Manual – Technical Manual – Signaling and

Protocols – Chapter 6 SIP



4

About this Session About this Session

Overview

Message Structure

Call Flow



5

OverviewOverview

SoftX3000 supports such call control protocols as ISUP,

SIP, H.323, etc. ISUP is used for interworking with the exi

sting PSTN while SIP and H.323 protocols are used for int

erworking with SIP domain, H.323 domain or other softsw

itch systems



6

Concept of SIPConcept of SIP

The Session Initiation Protocol (SIP) is an application-layer

control protocol used to establish, modify and terminate

multimedia sessions or calls. These multimedia sessions

include multimedia conferences, remote education, Internet

telephony and similar applications.

SIP can be used to initiate sessions as well as inviting

members to sessions that have been advertised and

established by other means.

SIP transparently supports name mapping and redirection

services, allowing the implementation of ISDN, IN, and

subscriber mobile services.



7

Support of SIP to MultimediaSupport of SIP to Multimedia

SIP is a light-weight signaling protocol, which can be

used in conjunction with other call setup and signaling

protocols.

SIP does not offer conference control services such as

site control or voting and does not prescribe how a

conference is to be managed, but SIP can be used to

introduce conference control protocols. SIP does not

allocate multicast addresses.

SIP can invite users to sessions with and without

resource reservation. SIP does not reserve resources

itself, but can convey to the invited system the

information necessary to do this.



8

Support of SIP to MultimediaSupport of SIP to Multimedia

SIP supports five facets of establishing and terminating

multimedia communications:

User location: determination of the end system to be used

for communication.

User capabilities: determination of the media and media

parameters to be used.

User availability: determination of the willingness of the

called party to engage in communications.

Call setup: "ringing", establishment of call parameters at

both called and calling party.

Call control : establish, modify and terminate multimedia

sessions or calls.



9

TermsTerms

Location Service

to obtain information about a called subscriber's possi

ble location(s).

Proxy、 Proxy sever

Redirect server

A redirect server is a server that accepts an SIP request,

maps the address into zero or more new addresses an

d returns these addresses to the client.

Registrar

A registrar is a server that accepts REGISTER requests.

A registrar is typically co-located with a proxy or redire

ct server and MAY offer location services.



10

TermsTerms

User Agent Client

A user agent client is a client application that

initiates the SIP request.

User Agent Server

A user agent server is a server application that

contacts the user when a SIP request is received

and that returns a response on behalf of the user.

The response accepts, rejects or redirects the

request.

User Agent

An application which contains both a user agent

client and user agent server.



11

Protocol StackProtocol Stack

H.323 SIP RTSP RSVP RTCPH.263 etc.

RTP

TCP UDP

IP

PPP

Sonet

AAL3/4 AAL5

ATM Ethernet

PPP

V.34



12

SoftX3000

SoftPhoneIP Core

SoftX3000

SoftPhone

SIP/SIP-TSI

PSIPIP IP

IP IP

SIP Implementation in Softx3000SIP Implementation in Softx3000



13


Overview

Message Structure

Call Flow



14

Classification of SIP MessagesClassification of SIP Messages

There are two types of messages :

Request messages:

sent by the client to the server

including : INVITE, ACK, BYE, CANCEL, REGISTER,OPTION, etc.

Response messages:

Used to display the responses of the server to the requests of client

s

including 1xx, 2xx, 3xx, 4xx, 5xx and 6xx and ACK.

Both the request and response messages contain SIP head

er fields and SIP message fields.。



15

Request MessagesRequest Messages

Message Function

INVITE To initiate a session request

ACK The response message to the INVITE message

BYE End session command

CANCEL To cancel an unfinished request

REGISTER Register

OPTIONS To query the server’s capabilities.

INFO Interactive contents when a call is being

processed.

MESSAGE Short message

SUBSCRIBE To subscribe an event

NOTIFY To send event notice



16

Response MessagesResponse Messages

Message Function

1XX Temporary response

2XX Success

3XX Redirection

4XX Client error

5XX Server error

6XX Global failure



17

SIP Request Command FormatSIP Request Command Format

Command name Peer-end URL

Call-id: value

via: value

Protocol version

Message Header

Parameter line

To: value

Contact: value

From: value

Content-Length: value

Max-Forward: value

White Space

SDP

Content-Type: value

Cseq: value



18

Example of SIP Request Message Example of SIP Request Message

INVITE sip:[email protected]:5060;User=phone SIP/2.0

Call-ID:[email protected]

Via:SIP/2.0/UDP 127.0.0.1:5061

From:<sip:[email protected]:5061;User=phone>;tag=29005

358336B534F610A000

To:<sip:[email protected]:5060;User=phone>

Contact: sip:[email protected]:5061

CSeq:1 INVITE



19

Example of SIP Request Message (Cont.)Example of SIP Request Message (Cont.)

Max-Forwards:70

Content-Type: application/SDP

Content-Length:168

v=0

o=UserA 2890844526 2890844526 IN IP4 here.com

s=Session SDP

c=IN IP4 192.0.0.1

t=0 0



20

Example of SIP Request Message (Cont.)Example of SIP Request Message (Cont.)

m=audio 49172 RTP/AVP 0 8

a=rtpmap:0 PCMU/8000

a=rtpmap:8 PCMA/8000

a=sendonly



21

Response FormatResponse Format

SIPProtocol version Response message header

Call-id: value

via: value

Message header

parameter

To: value

Contact: value

From:value

Content-Length: value

Max-Forward: value

White Space

SDP

Content-Type: value

Cseq: value



22

Example of SIP Response MessageExample of SIP Response Message

SIP/2.0 200 OK

Content-Type:application/SDP

Via:SIP/2.0/UDP 127.0.0.1:5061

Call-ID:[email protected]

CSeq:1 INVITE

From:<sip:[email protected]:5061;User=phone>;tag=29005

358336B534F610A000

To:<sip:[email protected]:5060;User=phone>;tag=5358336B5

34F2900CD1B0000

Contact:<sip:[email protected]:55061>



23

Example of SIP Response Message (Cont.) Example of SIP Response Message (Cont.)

Content-Length:156

v=0

o=HuaweiSoftX3000 1073741824 1073741824 IN IP4

127.0.0.1

s=Sip Call

c=IN IP4 110.111.112.113

t=0 0

m=audio 5060 RTP/AVP 0

a=rtpmap:0 PCMU/8000



24


Overview

Message Structure

Call Flow



25

Registration FlowRegistration Flow

SoftX3000SIP Phone

Register

401 Unauthorized

Register

200 OK



26

SoftX3000SIP PhoneA SIP PhoneB

INVITE1

100 Trying2

INVITE3

100 Trying4

180 Ringing5180 Ringing6

200 OK8200 OK7

SIP Phone to SIP Phone SIP Phone to SIP Phone



27

SoftX3000SIP PhoneA SIP PhoneB

Conversation

ACK9

ACK10

BYE11

200 OK12

BYE13

200 OK14

SIP Phone to SIP Phone (cont.)SIP Phone to SIP Phone (cont.)



28

SoftX3000SoftX3000

INVITE1

100 Trying2

180 Ringing3

200 OK4

ACK5

BYE6

200 OK 7

Call Between SIP Trunk Call Between SIP Trunk



29

SGA SoftX3000A SoftX3000B SGB

IAMIAM

ACM

ANM

ANM

REL

REL

RLC

RLC

Conversation

INVITE1

100 Trying2

180 Ring3

200 OK4

ACK5

BYE6

200 OK7

ACM

Successful call flow with SIP-T Successful call flow with SIP-T



30

Summary Summary

SIP is used to establish, modify and terminate a multimedia

conference, such as conference call over Internet. SIP can be

used to initiate sessions as well as inviting members to

sessions that have been advertised and established by other

means.

SIP request messages: SIP messages sent by a client to the

server on the basis of designated operation for activation,

which include such messages as INVITE, PRACK, BYE,

CANCEL, UPDATE, etc.

SIP Response Messages: Used to display the status of the

requests sent by clients to the server, including the 1xx, 2xx,

3xx, 4xx, 5xx and 6xx responses and ACK.

The functions of each command in SIP call process should be

mastered as the key points.



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0aa000007 Sip Protocol Issue2.0