Cisco Cisco Expressway
Configuring NAPTR on a DNS Server
A DNS server that can be queried by the Expressway for ENUM lookups needs to be configured with NAPTR records
containing a <reverse digit order dotted E164 number> mapped to a routable address or regular expression to convert
the dialed number into a routable address + transport specification (SIP or H.323)
containing a <reverse digit order dotted E164 number> mapped to a routable address or regular expression to convert
the dialed number into a routable address + transport specification (SIP or H.323)
BIND Style Configuration
For example, setting up:
■
557120 to call john.smith@example.com using SIP or H.323
■
557121 to call mary.jones@example.com using SIP
■
557122 to call peter.archibald@myco.com using H.323
/etc/named.conf File
The named.conf file specifies (among other things) zones with specific domains and the files (in the /var/named
directory) that specify the zones’ configuration.
directory) that specify the zones’ configuration.
For example:
zone "enum.search.com." IN {
type master;
file "enum.enumlookups";
};
/var/named/<filename>
Contained in the file /var/named/enum.enumlookups are the details of the configuration of the zone; for an enum zone
this contains the Start Of Authority header followed by the NAPTR records containing the reverse ordered dotted digit
lookups, their translations and details of the protocol to use to route the call.
this contains the Start Of Authority header followed by the NAPTR records containing the reverse ordered dotted digit
lookups, their translations and details of the protocol to use to route the call.
For example:
$TTL 60
@INSOA<server name> root (
2009041201 ; serial number !!! change this to update record
60 ; refresh period
60 ; retry time
120 ; expire time
60 ; min ttl
)
SOA = Start of Authority record
INNS<server name>
NS = Name Server name
0.2.1.7.5.5 IN NAPTR 10 100 "u" "E2U+sip" "!^.*$!john.smith@example.com!" .
IN NAPTR 12 100 "u" "E2U+h323" "!^.*$!john.smith@example.com!" .
1.2.1.7.5.5 IN NAPTR 10 100 "u" "E2U+sip" "!^.*$!mary.jones@example.com!" .
2.2.1.7.5.5 IN NAPTR 10 100 "u" "E2U+h323" "!^.*$!peter.archibald@myco.com!" .
<digits dotted and reversed>
IN = Internet routing
NAPTR = record type
10 = order value (use lowest order value first)
100 = preference value if multiple entries have the same
order value
"u" = the result is a routable URI
"E2U+sip" to make SIP call
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Cisco Expressway ENUM Dialing Deployment Guide