Cisco Cisco TelePresence Video Communication Server Expressway 관리 매뉴얼
URI Dialing Without DNS
Without the use of DNS, calls made by a locally registered endpoint using URI dialing will be placed only if the
destination endpoint is also locally registered, or is accessible via a neighbor system. This is because these endpoints
would be located using the
destination endpoint is also locally registered, or is accessible via a neighbor system. This is because these endpoints
would be located using the
, rather than a DNS query.
If you want to use URI dialing from your network without the use of DNS, you would need to ensure that all the
systems in your network were connected to each other by neighbor relationships - either directly or indirectly. This
would ensure that any one system could locate an endpoint registered to itself or any another system, by searching
for the endpoint's URI.
systems in your network were connected to each other by neighbor relationships - either directly or indirectly. This
would ensure that any one system could locate an endpoint registered to itself or any another system, by searching
for the endpoint's URI.
This does not scale well as the number of systems grows. It is also not particularly practical, as it means that
endpoints within your network will not be able to dial endpoints registered to systems outside your network (for
example when placing calls to another company) if there is not already a neighbor relationship between the two
systems.
endpoints within your network will not be able to dial endpoints registered to systems outside your network (for
example when placing calls to another company) if there is not already a neighbor relationship between the two
systems.
If a DNS zone and a DNS server have not been configured on the local VCS, calls to endpoints that are not registered
locally or to a neighbor system could still be placed if the local VCS is neighbored (either directly or indirectly) with
another VCS that has been configured for URI dialing via DNS. In this case, any URI-dialed calls that are picked up by
search rules that refer to that neighbor zone will go via that neighbor, which will perform the DNS lookup.
locally or to a neighbor system could still be placed if the local VCS is neighbored (either directly or indirectly) with
another VCS that has been configured for URI dialing via DNS. In this case, any URI-dialed calls that are picked up by
search rules that refer to that neighbor zone will go via that neighbor, which will perform the DNS lookup.
This configuration is useful if you want all URI dialing to be made via one particular system, such as a VCS
Expressway.
Expressway.
If you do not want to use DNS as part of URI dialing within your network, then no special configuration is required.
Endpoints will register with an alias in the form of a URI, and when calls are placed to that URI the VCS will query its
local zone and neighbors for that URI.
Endpoints will register with an alias in the form of a URI, and when calls are placed to that URI the VCS will query its
local zone and neighbors for that URI.
If the VCS does not have DNS configured and your network includes H.323 endpoints, then in order for these
endpoints to be reachable using URI dialing either:
endpoints to be reachable 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
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
SIP endpoints always register with an AOR in the form of a URI, so no special configuration is required.
URI Dialing With DNS
By using DNS as part of URI dialing, it is possible to find an endpoint even though it may be registered to an unknown
system. The VCS uses a DNS lookup to locate the domain in the URI address and then queries that domain for the
alias. See the
system. The VCS uses a DNS lookup to locate the domain in the URI address and then queries that domain for the
alias. See the
URI dialing via DNS is enabled separately for outgoing and incoming calls.
Outgoing calls
To enable your VCS to locate endpoints using URI dialing via DNS, you must:
■
configure at least one DNS zone and an associated search rule
■
configure at least one DNS server
section.
Incoming calls
To enable endpoints registered to your VCS to receive calls from non-locally registered endpoints using URI dialing
via DNS, you must:
via DNS, you must:
■
ensure all endpoints are registered with an AOR (SIP) or H.323 ID in the form of a URI
■
configure appropriate DNS records, depending on the protocols and transport types you want to use
199
Cisco TelePresence Video Communication Server Administrator Guide