Avaya 555-245-600 Benutzerhandbuch
Resource sizing
Issue 6 January 2008
201
Although we stated that calls between two circuit-switched endpoints on different port networks
use an IP connection, the use of a circuit-switched center stage between the two PNs is also
supported. However, using circuit-switched facilities is not viable for interconnecting multiple
Media Gateways, or for interconnecting PNs and Media Gateways.
use an IP connection, the use of a circuit-switched center stage between the two PNs is also
supported. However, using circuit-switched facilities is not viable for interconnecting multiple
Media Gateways, or for interconnecting PNs and Media Gateways.
provides some insight into how a call between an IP endpoint and a circuit-switched
endpoint, as well as a call between two circuit-switched endpoints, utilizes media processing
and TDM resources. Calls between IP endpoints are addressed first.
Communication Manager supports three general modes of connectivity between IP endpoints:
IP-TDM-IP connectivity, hairpinning, and shuffling. Hairpinning can take one of two forms: deep
or shallow. These various modes of connectivity are described in more detail below.
and TDM resources. Calls between IP endpoints are addressed first.
Communication Manager supports three general modes of connectivity between IP endpoints:
IP-TDM-IP connectivity, hairpinning, and shuffling. Hairpinning can take one of two forms: deep
or shallow. These various modes of connectivity are described in more detail below.
IP-TDM-IP connectivity
A call that uses IP-TDM-IP connectivity between two IP endpoints requires one bidirectional
media processing “channel” for each IP endpoint involved, as well as a bidirectional TDM
resource on every PN (or Media Gateway) that is involved in the call. This option most often
applies in systems that use a circuit-switched center stage for interport network connectivity. In
such a system, IP-TDM-IP is required in order for two IP endpoints in network regions not
configured for connectivity (in the sense of the IRCM matrix) to talk to one another.
media processing “channel” for each IP endpoint involved, as well as a bidirectional TDM
resource on every PN (or Media Gateway) that is involved in the call. This option most often
applies in systems that use a circuit-switched center stage for interport network connectivity. In
such a system, IP-TDM-IP is required in order for two IP endpoints in network regions not
configured for connectivity (in the sense of the IRCM matrix) to talk to one another.
Hairpinning
Unlike the IP-TDM-IP connectivity option, hairpinning requires that all media processing
resources for a given call reside on a single TN2302AP or TN2602AP media processing circuit
pack or a single G350 or G700 Media Gateway VoIP Media Module. A hairpinned call is
originally set up as an IP-TDM-IP call, but once the set-up process is complete, no TDM
resources are required. However, resources on the Media Processing circuit pack or VoIP
Media Module are required for the duration of the call. A Media Processing circuit pack and a
VoIP Media Module each house an onboard Central Processing Unit (CPU) and Digital Signal
Processors (DSPs).
resources for a given call reside on a single TN2302AP or TN2602AP media processing circuit
pack or a single G350 or G700 Media Gateway VoIP Media Module. A hairpinned call is
originally set up as an IP-TDM-IP call, but once the set-up process is complete, no TDM
resources are required. However, resources on the Media Processing circuit pack or VoIP
Media Module are required for the duration of the call. A Media Processing circuit pack and a
VoIP Media Module each house an onboard Central Processing Unit (CPU) and Digital Signal
Processors (DSPs).
Shuffling
A shuffled call relinquishes all TDM and media processing resources after call setup. Therefore,
the media stream of a shuffled call traverses only an IP network. This is the most commonly
used mode of connectivity between two IP endpoints in the same system.
the media stream of a shuffled call traverses only an IP network. This is the most commonly
used mode of connectivity between two IP endpoints in the same system.
on page 202 shows the various
modes of connectivity between two IP endpoints.