Cisco Cisco TelePresence Video Communication Server Expressway 관리 매뉴얼
Dial plan and call processing
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The Cisco VCS sends SRV queries for each result returned from the NAPTR record lookup. A
prioritized list of A/AAAA records returned is built.
prioritized list of A/AAAA records returned is built.
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The Cisco VCS sends an A/AAAA record query for each name record returned by the SRV
record lookup.
record lookup.
The above steps will result in a tree of IP addresses, port and transport protocols to be used to
contact the target domain. The tree is sub-divided by NAPTR record priority and then by SRV
record priority. When the tree of locations is used, the searching process will stop on the first
location to return a response that indicates that the target destination has been contacted.
contact the target domain. The tree is sub-divided by NAPTR record priority and then by SRV
record priority. When the tree of locations is used, the searching process will stop on the first
location to return a response that indicates that the target destination has been contacted.
2. If the search process does not return a relevant SRV record:
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If the Include address record setting for the DNS zone being queried is set to On, the system
will fall back to looking for an A or AAAA record for the domain in the URI. If such a record is
found, the call will be routed to that IP address and the search will terminate. Note that if the A
and AAAA records that are found at this domain are for systems other than those that support
SIP or H.323, the Cisco VCS will still forward the call to this zone, and the call will therefore
fail. For this reason, you are recommended to use the default setting of Off.
will fall back to looking for an A or AAAA record for the domain in the URI. If such a record is
found, the call will be routed to that IP address and the search will terminate. Note that if the A
and AAAA records that are found at this domain are for systems other than those that support
SIP or H.323, the Cisco VCS will still forward the call to this zone, and the call will therefore
fail. For this reason, you are recommended to use the default setting of Off.
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If the Include address record setting for the DNS zone being queried is set to Off, the Cisco
VCS will not query for A and AAAA records and instead will continue with the search, querying
the remaining lower priority zones.
VCS will not query for A and AAAA records and instead will continue with the search, querying
the remaining lower priority zones.
URI dialing via DNS for outgoing calls
When a user places a call using URI dialing, they will typically dial an address in the form
name@example.com from their endpoint. Below is the process that is followed when a URI address
is dialed from an endpoint registered with your Cisco VCS, or received as a query from a neighbor
system:
name@example.com from their endpoint. Below is the process that is followed when a URI address
is dialed from an endpoint registered with your Cisco VCS, or received as a query from a neighbor
system:
1. The Cisco VCS checks its
to see if any of them are configured with a Mode of either:
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Any alias, or
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Alias pattern match with a pattern that matches the URI address
2. The associated target zones are queried, in rule priority order, for the URI.
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If one of the target zones is a DNS zone, the Cisco VCS attempts to locate the endpoint
through a DNS lookup. It does this by querying the DNS server configured on the Cisco VCS
for the location of the domain as per the
through a DNS lookup. It does this by querying the DNS server configured on the Cisco VCS
for the location of the domain as per the
. If the domain part of
the URI address is resolved successfully the request is forwarded to those addresses.
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If one of the target zones is a neighbor, traversal client or traversal server zones, those zones
are queried for the URI. If that system supports URI dialing via DNS, it may route the call
itself.
are queried for the URI. If that system supports URI dialing via DNS, it may route the call
itself.
Adding and configuring DNS zones
To enable URI dialing via DNS, you must configure at least one DNS zone. To do this:
1. Go to the Zones page (
VCS configuration > Zones
).
2. Click New. You are taken to the Create zone page.
3. Enter a Name for the zone and select a Type of DNS.
3. Enter a Name for the zone and select a Type of DNS.
Cisco VCS Administrator Guide (X6)
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