Configuring Dns Servers For Enum And Uri Dialing - Cisco TelePresence Administrator's Manual

ENUM relies on the presence of NAPTR records, as defined by
H.323 or SIP URI from an E.164 number.
The record format that the VCS supports is:
order flag preference service regex replacement
where:
order and preference determine the order in which NAPTR records are processed. The record with the
n
lowest order is processed first, with those with the lowest preference being processed first in the case of
matching order.
flag determines the interpretation of the other fields in this record. Only the value u (indicating that this is
n
a terminal rule) is currently supported, and this is mandatory.
service states whether this record is intended to describe E.164 to URI conversion for H.323 or for SIP.
n
Its value must be either E2U+h323 or E2U+SIP.
regex is a regular expression that describes the conversion from the given E.164 number to an H.323 or
n
SIP URI.
replacement is not currently used by the VCS and should be set to . (the full stop character).
n
Non-terminal rules in ENUM are not currently supported by the VCS. For more information on these, see
section 2.4.1 of RFC 3761.
For example, the record:
IN NAPTR 10 100 "u" "E2U+h323" "!^(.*)$!h323:\1@example.com!" .
would be interpreted as follows:
10 is the order
n
100 is the preference
n
u is the flag
n
E2U+h323 states that this record is for an H.323 URI
n
!^(.*)$!h323:\1@example.com! describes the conversion:
n
! is a field separator
l
the first field represents the string to be converted. In this example, ^(.*)$ represents the entire E.164
l
number
the second field represents the H.323 URI that will be generated. In this example,
l
h323:\1@example.com states that the E.164 number will be concatenated with @example.com. For
example, 1234 will be mapped to 1234@example.com.
. shows that the replacement field has not been used.
n

Configuring DNS servers for ENUM and URI dialing

DNS servers are required to support ENUM and URI dialing:
ENUM dialing: to query for NAPTR records that map E.164 numbers to URIs
n
URI dialing: to look up endpoints that are not locally registered or cannot be accessed via neighbor
n
systems
To configure the DNS servers used by the VCS for DNS queries:
Cisco VCS Administrator Guide (X7.1)
Dial plan and call processing
RFC 2915. These are used to obtain an
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