Zone Configuration For Enum Dialing - Cisco TelePresence Administrator's Manual

If a target zone is an ENUM zone, the VCS attempts to locate the endpoint through ENUM. As and
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when each ENUM zone configured on the VCS is queried, the E.164 number is transformed into an
ENUM domain as follows:
i. The digits are reversed and separated by a dot.
ii. The DNS suffix configured for that ENUM zone is appended.
5. DNS is then queried for the resulting ENUM domain.
6. If the DNS server finds at that ENUM domain a NAPTR record that matches the transformed E.164
number (that is, after it has been reversed and separated by a dot), it returns the associated URI to the
VCS.
7. The VCS then initiates a new search for that URI (maintaining the existing hop count). The VCS starts at
the beginning of the search process (applying any pre-search transforms, then searching local and external
zones in priority order).From this point, as it is now searching for a SIP/H.323 URI, the process for
dialing is followed.
In this example, we want to call Fred at Example Corp. Fred's endpoint is actually registered with the URI
fred@example.com, but to make it easier to contact him his system administrator has configured a DNS
NAPTR record mapping this alias to his E.164 number: +44123456789.
We know that the NAPTR record for example.com uses the DNS domain of e164.arpa.
1. We create an ENUM zone on our local VCS with a DNS suffix of e164.arpa.
2. We configure a search rule with a Pattern match mode of Any alias, and set the Target to the ENUM
zone. This means that ENUM will always be queried regardless of the format of the alias being searched
for.
3. We dial 44123456789 from our endpoint.
4. The VCS initiates a search for a registration of 44123456789 and the search rule of Any alias means the
ENUM zone is queried. (Note that other higher priority searches could potentially match the number first.)
5. Because the zone being queried is an ENUM zone, the VCS is automatically triggered to transform the
number into an ENUM domain as follows:
a. The digits are reversed and separated by a dot: 9.8.7.6.5.4.3.2.1.4.4.
b. The DNS suffix configured for this ENUM zone, e164.arpa, is appended. This results in a
transformed domain of 9.8.7.6.5.4.3.2.1.4.4.e164.arpa.
6. DNS is then queried for that ENUM domain.
7. The DNS server finds the domain and returns the information in the associated NAPTR record. This tells
the VCS that the E.164 number we have dialed is mapped to the SIP URI of fred@example.com.
8. The VCS then starts another search, this time for fred@example.com. From this point the process for
URI dialing is followed, and results in the call being forwarded to Fred's endpoint.

Zone configuration for ENUM dialing

For locally registered endpoints to use ENUM dialing, you must configure an ENUM zone and related search
rules for each ENUM service used by remote endpoints.
Adding and configuring ENUM zones
To set up an ENUM zone:
Cisco VCS Administrator Guide (X7.1)
Dial plan and call processing
URI
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