Cisco Cisco Expressway Maintenance Manual
2. If the match is successful, any associated zone transform (where the Mode is Alias pattern match and the
Pattern behavior is Replace or Strip) is applied to the alias.
3. The search rule's Target zone or policy service is queried (with the revised alias if a zone transform has
been applied) using the same protocol (SIP or H.323) as the incoming call request. Note that if there are
many successful matches for multiple search rules at the same priority level, every applicable Target is
queried.
many successful matches for multiple search rules at the same priority level, every applicable Target is
queried.
l
If the alias is found, the call is forwarded to that zone. If the alias is found by more than one zone, the
call is forwarded to the zone that responds first.
call is forwarded to the zone that responds first.
l
If the alias is not found using the native protocol, the query is repeated using the interworked protocol,
depending on the
depending on the
l
If the search returns a new URI or alias (for example, due to an ENUM lookup, or the response from a
policy service), the entire
policy service), the entire
starts again
4. If the alias is not found, the search rules with the next highest priority are applied (go back to step 1) until:
l
the alias is found, or
l
all target zones and policy services associated with search rules that meet the specified criteria have
been queried, or
been queried, or
l
a search rule with a successful match has an On successful match setting of Stop searching
Note the difference between a successful match (where the alias matches the search rule criteria) and an
alias being found (where a query sent to a target zone is successful). The Stop searching option provides
better control over the network's signaling infrastructure. For example, if searches for a particular domain
should always be routed to a specific zone this option lets you make the search process more efficient and
stop the Expressway from searching any other zones unnecessarily.
alias being found (where a query sent to a target zone is successful). The Stop searching option provides
better control over the network's signaling infrastructure. For example, if searches for a particular domain
should always be routed to a specific zone this option lets you make the search process more efficient and
stop the Expressway from searching any other zones unnecessarily.
Configuring search rules
The
Search rules
page (
Configuration > Dial plan > Search rules
) is used to configure how the
Expressway routes incoming search requests to the appropriate target zones (including the Local Zone) or
policy services.
policy services.
The page lists all the currently configured search rules and lets you create, edit, delete, enable and disable
rules. You can click on a column heading to sort the list, for example by Target or Priority. If you hover your
mouse pointer over a search rule, the rule description (if one has been defined) appears as a tooltip.
rules. You can click on a column heading to sort the list, for example by Target or Priority. If you hover your
mouse pointer over a search rule, the rule description (if one has been defined) appears as a tooltip.
Up to 2000 search rules can be configured. Priority 1 search rules are applied first, followed by all priority 2
search rules, and so on.
search rules, and so on.
The configurable options are:
Field
Description
Usage tips
Rule name
A descriptive name for the search rule.
Description
An optional free-form description of the search
rule.
rule.
The description appears as a tooltip if you
hover your mouse pointer over a rule in the
list.
hover your mouse pointer over a rule in the
list.
Cisco Expressway Administrator Guide (X8.1.1)
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Dial plan and call processing
About transforms and search rules