Cisco Cisco TelePresence Video Communication Server Expressway
Routing Configuration
Pre-search Transforms
Pre-search transform configuration allows the destination alias (called address) in an incoming search request to be
modified. The transformation is applied by the VCS before any searches take place, either locally or to external zones.
modified. The transformation is applied by the VCS before any searches take place, either locally or to external zones.
The pre-search transform configuration described in this document is used to standardize destination aliases originating
from both H.323 and SIP devices. This means that the same call searches will work for calls from both H.323 and SIP
endpoints.
from both H.323 and SIP devices. This means that the same call searches will work for calls from both H.323 and SIP
endpoints.
For example, if the called address is an H.323 E.164 alias “01234”, the VCS will automatically append the configured
domain name (in this case example.com) to the called address (that is, 01234@example.com making it into a URI),
before attempting to set up the call.
domain name (in this case example.com) to the called address (that is, 01234@example.com making it into a URI),
before attempting to set up the call.
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Pre-search transforms should be used with care because they apply to all signaling messages – if they match,
they will affect the routing of Unified Communications messages, provisioning and presence requests as well as
call requests.
they will affect the routing of Unified Communications messages, provisioning and presence requests as well as
call requests.
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Transformations can also be carried out in search rules – consider whether it is best to use a pre-search transform
or a search rule to modify the called address to be looked up.
or a search rule to modify the called address to be looked up.
Search Rules
Search rules define how the VCS routes calls (to destination zones) in specific call scenarios. When a search rule is
matched, the destination alias can be modified according to the conditions defined in the search rule.
matched, the destination alias can be modified according to the conditions defined in the search rule.
The search rules described in this document are used to ensure that SIP (and H.323) endpoints can dial H.323 devices
that have registered E.164 numbers or H.323 IDs without a domain portion. The search rules first search for received
destination aliases without the domain portion of the URI, and then search with the full URI.
that have registered E.164 numbers or H.323 IDs without a domain portion. The search rules first search for received
destination aliases without the domain portion of the URI, and then search with the full URI.
The search rules described here are used to enable the following routing combinations:
Calling party
Called party
Registered devices (VCS Control or VCS Expressway)
Registered devices (VCS Control or VCS Expressway)
Registered devices (VCS Control or VCS Expressway)
External domains and un-registered devices (via VCS
Expressway using DNS zone)
Expressway using DNS zone)
Registered devices (VCS Control or VCS Expressway)
Public external IP addresses (via VCS Expressway)
External domains and un-registered devices
Registered devices (VCS Control or VCS Expressway)
The routing configuration in this document searches for destination aliases that have valid SIP URIs (that is, using a valid
SIP domain, such as id@domain).
SIP domain, such as id@domain).
You can configure routing which enables calls to unregistered devices on an internal network (routing to the addresses
of IP of the devices) by configuring a search rule with a mode of
of IP of the devices) by configuring a search rule with a mode of
Any IP address with target Local Zone. However this is
not recommended (and not described in this document). The best practice is to register all devices and route using
destination aliases.
destination aliases.
Task 7: Configuring Transforms
The pre-search transform configuration described in this document is used to standardize destination aliases originating
from both H.323 and SIP devices.
from both H.323 and SIP devices.
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Cisco VCS Expressway and VCS Control - Basic Configuration Deployment Guide