Cisco Cisco TelePresence Video Communication Server Expressway 관리 매뉴얼
URI Dialing via DNS for Incoming Calls
DNS record types
The ability of the VCS to receive incoming calls (and other messages, such as registrations) made using URI dialing
via DNS relies on the presence of DNS records for each domain the VCS is hosting.
via DNS relies on the presence of DNS records for each domain the VCS is hosting.
These records can be of various types including:
■
A records, which provide the IPv4 address of the VCS
■
AAAA records, which provide the IPv6 address of the VCS
■
Service (SRV) records, which specify the FQDN of the VCS and the port on it to be queried for a particular
protocol and transport type.
protocol and transport type.
■
NAPTR records, which specify SRV record and transport preferences for a SIP domain.
You must provide an SRV or NAPTR record for each combination of domain hosted and protocol and transport type
enabled on the VCS.
enabled on the VCS.
Incoming call process
When an incoming call has been placed using URI dialing via DNS, the VCS will have been located by the calling
system using one of the DNS record lookups described above. The VCS will receive the request containing the dialed
URI in the form user@example.com. This will appear as coming from the Default Zone. The VCS will then search for
the URI in accordance with its normal
system using one of the DNS record lookups described above. The VCS will receive the request containing the dialed
URI in the form user@example.com. This will appear as coming from the Default Zone. The VCS will then search for
the URI in accordance with its normal
, applying any pre-search transforms, Call Policy and
FindMe policy, then searching its Local Zone and other configured zones, in order of search rule priority.
SRV record format
_Service._Proto.Name TTL Class SRV Priority Weight Port Target
For the VCS, these are as follows:
■
_Service
and
_Proto
will be different for H.323 and SIP, and will depend on the protocol and transport type
being used
■
Name
is the domain in the URI that the VCS is hosting (such as
example.com
)
■
Port
is the IP port on the VCS that has been configured to listen for that particular service and protocol
combination
■
Target
is the FQDN of the VCS.
Configuring H.323 SRV Records
for resolving H.323 URL aliases. It also defines parameters for use with the H.323 URL.
The VCS supports the location, call and registration service types of SRV record as defined by this Annex.
Location service SRV records
Location records are required for gatekeepers that route calls to the VCS. For each domain hosted by the VCS, you
should configure a location service SRV record as follows:
should configure a location service SRV record as follows:
■
_Service
is
_h323ls
■
_Proto
is
_udp
■
Port is the port number that has been configured from Configuration > Protocols > H.323 as the Registration
UDP port
UDP port
203
Cisco TelePresence Video Communication Server Administrator Guide