Medias Mediatrix 1204, Reference Manual

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Chapter 18 - SIP Protocol Features SIP Transport Type
224 Mediatrix 1204
2. Enter the public IP address of the NAT system in the localHostStaticWanAddress variable.
This is the public IP address used as Contact address by outgoing SIP packets crossing a NAT
system.
NAT System Configuration
You must configure the NAT system to some degree. The configuration required depends on the type of NAT
system you are using, but this usually involves port forwarding configuration.
SIP Transport Type
You can globally set the transport type for all the lines of the Mediatrix 1204 to either UDP (User Datagram
Protocol) or TCP (Transmission Control Protocol). The Mediatrix 1204 will include its supported transports in
its registrations.
Please note that RFC 3261 states the implementations must be able to handle messages up to the maximum
datagram packet size. For UDP, this size is 65,535 bytes, including IP and UDP headers. However, the
maximum datagram packet size the Mediatrix 1204 supports for a SIP request or response is 5120 bytes
excluding the IP and UDP headers. This should be enough, as a packet is rarely bigger than 2500 bytes.
You can also set these parameters via the web interface, as described in “SIP Transport Type” on page 70 .
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To set the transport type:
3. In the sipMIB , set the priority order of the transport in the sipTransportQValue variable.
A qvalue parameter is added to each contact. This only applies if the transport-specific registration
is enabled.
The qvalue gives each transport a weight, indicating the degree of preference for that transport. A
higher value means higher preference.
The format of the qvalue string must follow the RFC 3261 ABNF (a floating point value between
0.000 and 1.000). If you specify an empty string, no qvalue is set in the contacts.
Because this variable is located in a table, you can have a different value for each line.
4. Enable the transport by setting the sipTransportEnable variable to enable .
The UDP and TCP transport types are located in a table with two rows – one for each type. You can
enable/disable a type for the unit.
If the TCP transport type is not used, Mediatrix strongly suggests to disable it.
5. Enable the transport registration by setting the sipTransportRegistrationEnable variable to enable .
The Mediatrix 1204 includes its supported transports in its registrations. It registers with one contact
for each transport that is currently enabled. Each of these contacts contains a “transport” parameter.
Standards Supported RFC 3261 – SIP: Session Initiation Protocol