User`s guide

MBR L13 – User’s Guide
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(for example, an IP phone). A SIP agent requires port forwarding configuration (refer to Section Port Forwarding,
which uses the same port—5060. This multiple use of the port causes failure of either or both services. Therefore,
when configuring port forwarding for a SIP agent, you must change L13 SIP port value (for example, to 5062).
Note that the calling party must be made aware of this value when initiating a direct call (not using a proxy).
Figure 104: Advanced – SIP
Set SIP related parameters:
Parameter
Description
Local SIP Port
L13 SIP protocol signaling port.
SIP Reconnect Timeout
The timeout for reconnecting the L13 SIP server
from each VoIP extension.
Use Strict SIP Message Checking
By default, L13 uses strict SIP message checking,
which includes checking of tags in headers,
international character conversions in URIs, and
multiline formatted headers. There are cases in
which this option should be disabled to ensure
interoperability with certain service providers or
third party user agents (SIP endpoints).
Enable Silence Suppression
Enables optimization when no speech is detected.
With this feature enabled, L13 is able to detect the
absence of audio and conserve bandwidth by
preventing the transmission of "silent packets" over
the network. By default this option is selected in
L13.
 To change the RTP start port (administrator only):
The voice stream is transmitted in Real Time Protocol (RTP) packets, which require a range of open ports. If the
default ports are required for another application, you can enter a different start port, thereby creating a new
range.
Under the Local RTP Port Range, specify the first port in the range of 16 ports to reserve for Real Time Protocol
(RTP) voice transport.
Figure 105: Advanced – RTP
 To configure the QoS parameters (administrator only):
Quality of Service (QoS) is aimed at improving the quality of voice traffic over VoIP external line.
In the Quality of Service section, configure the following options: