Cisco Cisco Expressway
Introduction
ENUM (E.164 Number Mapping) is a way of using DNS NAPTR (Name Authority PoinTeR) records to convert E.164
numbers into routable URIs. ENUM is defined in RFC 3761.
numbers into routable URIs. ENUM is defined in RFC 3761.
This document describes how to configure your network and your Cisco Expressway (Expressway) to enable calls to be
placed from inside or outside your network using ENUM dialing to endpoints that have registered using a URI.
placed from inside or outside your network using ENUM dialing to endpoints that have registered using a URI.
To support this deployment scenario:
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The Expressway must be configured with an ENUM zone and associated search rule that:
—
removes any suffixes, producing a digit-only dial string
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specifies a DNS domain where the NAPTR records for that E.164 can be found
■
The Expressway must be configured with the address of at least one DNS server that is capable of resolving the
NAPTR search request.
NAPTR search request.
■
A DNS server must be configured with NAPTR records that:
—
define (using regular expressions) the way in which a presented E.164 number is converted to a routable URI
—
define the transport protocol to be used for the call (SIP or H.323)
These steps are described in detail in the sections that follow.
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Cisco Expressway ENUM Dialing Deployment Guide