Cisco Cisco Expressway Maintenance Manual
Protocols
This section provides information about how to configure the Expressway to support the SIP and H.323 protocols.
Configuring H.323
Go to Configuration > Protocols > H.323 to configure the H.323 settings on the Expressway.
The configurable options are:
Field
Description
Usage tips
H.323 mode
Enables or disables H.323 on the Expressway.
H.323 support is On by default.
H.323 support is On by default.
You must enable H.323 mode if you are
clustering the Expressway, even if there are no
H.323 endpoints in your deployment.
clustering the Expressway, even if there are no
H.323 endpoints in your deployment.
Call signaling
TCP port
TCP port
The listening port for H.323 call signaling. Default
is 1720.
is 1720.
Call signaling
port range
start and end
start and end
Specifies the lower port in the range used by
H.323 calls after they are established. Default is
15000.
H.323 calls after they are established. Default is
15000.
The call signaling port range must be great
enough to support all the required concurrent
calls.
enough to support all the required concurrent
calls.
Call time to
live
live
The interval (in seconds) at which the
Expressway polls the endpoints in a call to verify
that they are still in the call. Default is 120.
Expressway polls the endpoints in a call to verify
that they are still in the call. Default is 120.
If the endpoint does not respond, the call will
be disconnected.
be disconnected.
Auto
discover
discover
Determines whether it will respond to Gatekeeper
Discovery Requests sent out by endpoints. The
default is On.
Discovery Requests sent out by endpoints. The
default is On.
About SIP
The Expressway supports the SIP protocol. It can act as a SIP registrar and proxy.
The Expressway can provide interworking between SIP and H.323, translating between the two protocols to enable
endpoints that only support one of these protocols to call each other.
endpoints that only support one of these protocols to call each other.
To support SIP:
■
■
At least one of the SIP transport protocols (UDP, TCP or TLS) must be active. Note that the use of UDP is not
recommended for video as SIP message sizes are frequently larger than a single UDP packet.
recommended for video as SIP message sizes are frequently larger than a single UDP packet.
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