User`s manual
H.323 User's Manual 5. Web Management
Version 5.0 101 December 2006
The call is then sent to the VoIP gateway channels assigned to that trunk group. The
specific channel, within a trunk group that is assigned to accept the call is determined
according to the trunk group’s channel selection mode which is defined in the Trunk Group
Settings screen (Section 5.5.10 on page 124) or according to the global parameter
‘ChannelSelectMode’ (refer to Table 5-7 on page 80). Trunk groups can be used on both
FXO and FXS modules; however, usually they are used with FXO modules.
Notes:
• When a Gatekeeper is used, before an incoming call is being routed to
the relevant trunk group an Admission request is sent to the
Gatekeeper. Calls that aren’t authorized are dropped. When the
parameter ‘PreferRouteTable’ is set to 1, the gateway checks the
'Source IP Address' field in the 'IP to Trunk Group Routing' table for a
match with the incoming call. If such a match is found, the call is
routed. If a match is not found, an Admission request is sent to the
Gatekeeper.
• When a release reason that is defined in the ‘Reasons for Alternative
IP to Tel Routing’ table is received for a specific IPÆTel call, an
alternative trunk group for that call is available. To associate an
alternative trunk group to an incoming IP call, assign it with an
additional entry in the ‘IP to Trunk Group Routing’ table (repeat the
same routing rules with a different trunk group ID). For detailed
information on the ‘Reasons for Alternative Routing Tables’, refer to
Section 5.5.4.5 on page 104.
To use trunk groups you must also do the following.
You must assign a trunk group ID to the VoIP gateway channels in the Trunk Group
Table screen. For information on how to assign a trunk group ID to a channel, refer to
Section 5.5.9 on page 122.
You can configure the Trunk Group Settings table to determine the method in which
new calls are assigned to channels within the trunk groups (a different method for
each trunk group can be configured). For information on how to enable this option,
refer to Section 5.5.10 on page 124. If a Channel Select Mode for a specific trunk
group isn’t specified, then the global ‘Channel Select Mode’ parameter (defined in
‘General Parameters’ screen under ‘Advanced Parameters’) applies.
You can also configure the IP to Trunk Group Routing table using the ini file parameter
PSTNPrefix (refer to Section 6.5.9 on page 236).