Cisco Cisco TelePresence Video Communication Server Expressway 관리 매뉴얼
■
SRV record for
_sip._tcp.example.com
returns
vcs.example.com
■
SRV record for
_sips._tcp.example.com
returns
vcs.example.com
■
A record for
vcs.example.com
returns the IPv4 address of the VCS
■
AAAA record for
vcs.example.com
returns the IPv6 address of the VCS
How you add the DNS records depends on the type of DNS server you are using. Instructions for setting up two
common DNS servers are given in the
common DNS servers are given in the
section.
For locally registered H.323 endpoints to be reached using URI dialing, either:
■
the H.323 endpoints should register with the VCS using an address in the format of a URI
■
an appropriate transform should be written to convert URIs into the format used by the H.323 registrations. An
example would be a deployment where H.323 endpoints register with an alias, and incoming calls are made to
alias@domain.com. A local transform is then configured to strip the @domain, and the search is made locally
for alias. See
example would be a deployment where H.323 endpoints register with an alias, and incoming calls are made to
alias@domain.com. A local transform is then configured to strip the @domain, and the search is made locally
for alias. See
for an example of how to do this.
SIP endpoints always register with an AOR in the form of a URI, so no special configuration is required.
Several mechanisms could have been used to locate the VCS. You may want to enable calls placed to
user@<IP_
address>
to be routed to an existing registration for
user@example.com
example.com
.
URI Dialing and Firewall Traversal
If URI dialing via DNS is being used in conjunction with firewall traversal, DNS zones should be configured on the VCS
Expressway and any VCSs on the public network only. VCSs behind the firewall should not have any DNS zones
configured. This will ensure that any outgoing URI calls made by endpoints registered with the VCS will be routed
through the VCS Expressway.
Expressway and any VCSs on the public network only. VCSs behind the firewall should not have any DNS zones
configured. This will ensure that any outgoing URI calls made by endpoints registered with the VCS will be routed
through the VCS Expressway.
In addition, the DNS records for incoming calls should be configured with the address of the VCS Expressway as the
authoritative gatekeeper/proxy for the enterprise (the
authoritative gatekeeper/proxy for the enterprise (the
section for more
information). This ensures that incoming calls placed using URI dialing enter the enterprise through the VCS
Expressway, allowing successful traversal of the firewall.
Expressway, allowing successful traversal of the firewall.
About ENUM Dialing
ENUM dialing allows an endpoint to be contacted by a caller dialing an E.164 number - a telephone number - even if
that endpoint has registered using a different format of alias.
that endpoint has registered using a different format of alias.
Using ENUM dialing, when an E.164 number is dialed it is converted into a URI using information stored in DNS. The
VCS then attempts to find the endpoint based on the URI that has been returned.
VCS then attempts to find the endpoint based on the URI that has been returned.
The ENUM dialing facility allows you to retain the flexibility of URI dialing while having the simplicity of being called
using just a number - particularly important if any of your callers are restricted to dialing using a numeric keypad.
using just a number - particularly important if any of your callers are restricted to dialing using a numeric keypad.
The VCS supports outward ENUM dialing by allowing you to configure ENUM zones on the VCS. When an ENUM zone
is queried, this triggers the VCS to transform the E.164 number that was dialed into an ENUM domain which is then
queried for using DNS.
is queried, this triggers the VCS to transform the E.164 number that was dialed into an ENUM domain which is then
queried for using DNS.
Note:
ENUM dialing relies on the presence of relevant DNS NAPTR records for the ENUM domain being queried. These
are the responsibility of the administrator of that domain.
ENUM Dialing Process
When the VCS attempts to locate a destination endpoint using ENUM, the general process is as follows:
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Cisco TelePresence Video Communication Server Administrator Guide