Cisco Cisco Expressway
Appendix 4: Additional information
IP address dialing
Unified CM cannot dial out to IP addresses, but the Expressway can. To support IP address dialing from
endpoints registered to Unified CM, we recommend the following procedure:
endpoints registered to Unified CM, we recommend the following procedure:
1. Define a prefix to use for dialing the IP address, for example 8.
2. Add a Route Pattern in Unified CM to match the prefix and send it via the SIP trunk to Expressway.
3. On Expressway, add a search rule (or transform) with a regex to match, for example: 8(\d{3})(\d
{3})(\d{3})(\d{3}).*
and then replace it with \1.\2.\3.\4
This example regex matches an IP address dialed in the format of 12 digits (inserting the leading zeroes in
each octet), so for example 64.102.6.247 would be dialed as prefix 8 followed by 064102006247. The
replace string then inserts dots after the 3rd, 6th and 9th digits.
each octet), so for example 64.102.6.247 would be dialed as prefix 8 followed by 064102006247. The
replace string then inserts dots after the 3rd, 6th and 9th digits.
Characters allowed in SIP URIs
The following character set is allowed in SIP URIs (further details may be found in RFC 3261):
a-z / A-Z / 0-9 / "-" / "_" / "." / "!" / "~" / "*" / "'"/ "(" / ")" "&" / "=" / "+" / "$" / "," / ";" / "?" / "/"
If other characters are needed they must be “escaped” using "%" followed by a pair of hexadecimal digits that
represents the ASCII value for the required character.
represents the ASCII value for the required character.
For example, "alice smith@example.com" must be encoded as alice%20smith@example.com (where %20
represents the space character).
represents the space character).
Unified CM with Cisco Expressway (SIP Trunk) Deployment Guide (X8.1)
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Appendix 4: Additional information