Sip Network Definitions; Sip Dialog Initiation Process - AudioCodes Mediant 3000 User Manual


SIP normalization: The device supports SIP normalization, whereby the SBC
application can overcome interoperability problems between SIP user agents. This is
achieved by the following:
•
Manipulation of SIP URI user and host parts
•
Connection to ITSP SIP trunks on behalf of an IP-PBX - the device can register
and utilize user and password to authenticate for the IP-PBX

Survivability: The device's SBC application provides two survivability features:
•
Routing calls to alternative routes such as the PSTN
•
Routing calls between user agents in the local network using a dynamic database
(built according to registrations of SIP user agents)

Routing:
•
IP-to-IP routing translations of SIP, UDP, TCP, TLS (when extensive transcoding
is not required)
•
Load balancing and redundancy of SIP servers
•
Routing according to Request-URI\Specific IP address\Proxy\FQDN
•
Alternative routing
•
Routing between different Layer-3 networks (e.g., LAN and WAN)

Load balancing\redundancy of SIP servers

Internet Telephony Service Providers (ITSP) accounts

SIP URI user and host name manipulations

Coder Transcoding

19.1.1 SIP Network Definitions

The device's SBC application can implement multiple SIP signaling and RTP (media)
interfaces. For more information, see 'Mutiple SIP Signaling/Media Interfaces Environment'
on page 221.

19.1.2 SIP Dialog Initiation Process

The device's SIP dialog initiation process concerns all incoming SIP dialog initiation
requests. This includes SIP methods such as INVITE, SUBSCRIBE, OPTIONS, REFER,
INFO, UNSOLICITED NOTIFY, MESSAGE, and REGISTER.
The SIP dialog initiation process consists of the following stages:

Determining Source and Destination URL (see 'Determining Source and Destination
URL' on page 362)

Classifying Source IP Group (see 'Source IP Group Classification' on page 362)

IP-to-IP Routing (see 'SBC IP-to-IP Routing' on page 363)

Manipulating IP-to-IP Inbound and Outbound SIP dialogs (see 'IP-to-IP Inbound and
Outbound Manipulation' on page 364)
For a description of the Registration process, see 'User Registration and Internal Database'
on page 367.
SIP User's Manual 360
Mediant 3000
Document #: LTRT-89712