Dial plan

From Snom Asterisk Portal

Contents 1 Feature description 2 Configure Asterisk 3 Configure snom phones 3.1 snom 3xx 3.1.1 Firmware versions 6 and 7 3.2 snom m3

Feature description

"Dialplan" can refer either to the Asterisk dialplan (extensions.conf) or to the dialplan feature of the snom 3xx phones.

This article describes how to configure the snom phones dialplan feature in conjunction with the Asterisk PBX, which has its own, more flexible dialplan.

With the snom phones dialplan, you can match user input (digits via keyboard) to specific actions like dialing, using a distinct outgoing identity, etc. For a more detailed description of the dialplan feature on the snom phones, have a look at the white paper “Dial plan on snom phone” on our website.

Configure Asterisk

The most common case where you would use the phones dialplan feature is attaching the area code to a dialed local number. (e.g. transform local number "1234" to "030-1234" for the VoIP provider, but do not transform dialed numbers that already start with an area code)

This can be achieved in the Asterisk's dialplan. Below is an example implementation of extensions.conf, presumed your phones have their "context" set to "internal" in sip.conf.

[globals]
AREACODE=030

[internal]
include => dialout
exten => _XX,1,Dial(SIP/${EXTEN})
exten => _XX,n,Congestion

[dialout]
exten => _0XX.,1,Dial(SIP/trunk/${EXTEN})
exten => _0XX.,n,Congestion

exten => _XXX.,1,Dial(SIP/trunk/${AREACODE}${EXTEN})
exten => _XXX.,n,Congestion

In this example, Asterisk will append the local area code to each dialed number that is not prefixed with "0". (The example is valid for germany: When you dial across areas, the number is always prefixed with "0")

Configure snom phones

It is suggested to disable the snom phone's dialplan entirely and let the PBX handle call routing instead. That way it is guaranteed that all extensions have the same behavior. If a phone used its own dialplan, this would make debugging a complex asterisk dialplan even more complex.

snom 3xx

Firmware versions 6 and 7

1. Disable the feature by clearing out the contents of the input field beside the setting "Dial Plan String" via the Web User Interface under "Identity X" > tab "SIP" -> "Dial Plan String". Set this option to an empty string.

snom m3

The snom m3 does not support the "Dial Plan String" feature.