Cisco Cisco Customer Voice Portal 8.0(1)
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Cisco Internet Service Node (ISN) Product Description
OL-1250-03
Chapter 4 VoIP Routing
Inbound Routing
Each ISN node contains three Voice Browsers, with the IP addresses shown, each of the Voice Browsers
is registered with its Gatekeeper, and the Gateways are configured to perform RAS lookups in their
Gatekeeper for incoming calls.
is registered with its Gatekeeper, and the Gateways are configured to perform RAS lookups in their
Gatekeeper for incoming calls.
Figure 4-2
Inbound Call Routing, With Gatekeepers
The Gatekeeper is divided into three logical Gatekeepers (GK1, GK2, and GK3); the ISN Nodes register
with their appropriate Gatekeeper. Gateways would, in turn, be assigned to a zone, based upon the
nearest ISN node. Each logical Gatekeeper is configured with the same list of supported numbers, but
associated with Voice Browsers in their own zone’s ISN node. (For example, GK1 would point
800-555-0010 toward Voice Browsers at ISN_Node1, while GK2 would point 800-555-0010 toward
Voice Browsers at ISN_Node2.)
with their appropriate Gatekeeper. Gateways would, in turn, be assigned to a zone, based upon the
nearest ISN node. Each logical Gatekeeper is configured with the same list of supported numbers, but
associated with Voice Browsers in their own zone’s ISN node. (For example, GK1 would point
800-555-0010 toward Voice Browsers at ISN_Node1, while GK2 would point 800-555-0010 toward
Voice Browsers at ISN_Node2.)
Calls which enter the IP network thorough a Gateway in Zone 1 (GW Huey) would query GK1 for
routing information, which would return the IP Address for a Voice Browser at ISN_Node1.
routing information, which would return the IP Address for a Voice Browser at ISN_Node1.
Note
More than one ISN node may be placed in each zone, in which case prioritized routing and/or alternate
endpoints capabilities may also be used. However, alternate endpoints cannot be used to reroute calls to
a different zone if all targets in the first zone are unreachable.
endpoints capabilities may also be used. However, alternate endpoints cannot be used to reroute calls to
a different zone if all targets in the first zone are unreachable.
Another method of implementing nearest node routing is to use multiple tech-prefixes, where
“neighboring” Gateways and Voice Browsers can be configured to support the same tech-prefix.
Referring to
“neighboring” Gateways and Voice Browsers can be configured to support the same tech-prefix.
Referring to
again:
•
The Voice Browsers at ISN_Node1 would register at a Gatekeeper with the tech-prefix 2#.
•
The Voice Browsers at ISN_Node2 would register at the same Gatekeeper with the tech-prefix 3#.
•
Gateway Huey’s dial-peers would be configured to pre-pend 2# to all RAS queries to the Gatekeeper.
•
Gateway Dewey’s dial-peers would be configured to pre-pend 3# to all RAS queries to the
Gatekeeper.
Gatekeeper.
With this configuration in place, when Huey performs a RAS lookup at the Gatekeeper, the Gatekeeper
will only return IP addresses for the Voice Browser’s at ISN_Node1.
will only return IP addresses for the Voice Browser’s at ISN_Node1.
Note
For detailed instructions on how to configure Gatekeepers for inbound routing, see the Cisco Internet
Service Node (ISN) Configuration and Administration Guide.
Service Node (ISN) Configuration and Administration Guide.