This area is for handsets, softphones, paging systems, or anything
else that could be considered an 'extension' in the classical PBX
Defining and editing extensions is probably the most common task
performed by a PBX administrator, and as such, you'll find you'll
become very familiar with this page. There are presently four types of
devices supported - SIP, IAX2, ZAP and 'Custom'. This page also
configures how voicemail is handled on a per-extension basis.
Adding a new extension
Pick one of SIP, IAX, ZAP or Custom
- SIP is the Standard protocol for VoIP handsets and ATA's. The Session Initiation Protocol (SIP) is a signalling protocol, widely used for setting up and tearing down multimedia communication sessions such as voice and video calls over the Internet.
- IAX is 'Inter Asterisk Protocol', a newer protocol supported by only a few devices (eg, PA1688 based phones, and the IAXy ATA)
- ZAP is a hardware device connected to your Asterisk machine - Eg, a TDM400, TE110P.
- Custom is a 'catch all', for any non standard device, eg
H323. It can also be used for "mapping" an extension to an "outside"
number. For example, to route extension 211 to 1-800-555-1212, you
could create a custom extension 211 and in the "dial" text box you
could enter: Local/18005551212@outbound-allroutes
This must be unique. This is the number that can be dialled from any other extension, or directly from the Digital Receptionist if enabled. This
may be any length, but conventionally a three or four digit extension is used.
CID Num Alias The CID Number to use for internal calls, if different from
the extension number. This is used to masquerade as a different user. A
common example is a team of support people who would like their internal
callerid to display the general support number (a ringgroup or queue).
There will be no effect on external calls.
SIP AliasIf you want to support direct sip dialing of users internally
or through anonymous sip calls, you can supply a friendly name that can
be used in addition to the users extension to call them.
Secret, aka 'Extension Password'
This is the password used by the telephony device to authenticate
to the Asterisk server. This is usually configured by the administrator
before giving the phone to the user, and is usually not required to be
known by the user. If the user is using a soft-phone, then they'll need
to know this password to configure their software.
very important to set this to 'yes' if you want to be able to use
your phone behind a nat firewall seperate from the lan that your
asterisk box is on.
disallow any codec you do not want to use. common setting for this
if you want to make sure a device only uses the codec set in the allow
section is "all" (without the quotes).
allow a codec of your choice. primarily as an example i would use
"g729" or "GSM" (without the quotes), only one codec can be set here.
This is usefull if used with the disallow option set to "all" and you
set the definitive codec you want to use on allow, garunteing that you
will use that codec.
This option allows you to set what mailbox you would like to use.
Normally you would use 'your extension'@device . but if you want to say
have an extension's phone's light or dial tone indicate when a
different box has voicemail you can set it to 'extension vm'@device. so
say extension 1002 wants to know when 1001 has vm, then set this to
1001@device on 1002's mailbox setting.
Option to record the calls received on this extension. There are three options:
- On-Demand (User can dial '*1' to enable whilst in a call)
Same as above but for outgoing calls
Voicemail and Directory
Selecting 'Disabled' turns off voicemail for this extension totally, and these further options are hidden.
This is the password used to access the voicemail system (*98). It
can be changed by the user when they log into their voicemail (after
logging in, they dial 0 then 5).
The address that voicemails notifications will be sent to
Pager email address
This email address will be sent a small message notifying of voicemail messages, suitable for an email-to-pager service.
Read back caller's telephone number prior to playing the incoming
message, and just after announcing the date and time the message was
Envelope controls whether or not the voicemail system will play
the message envelope (date/time) before playing the voicemail message.
This settng does not affect the operation of the envelope option in the
advanced voicemail menu.
If set to "yes" the message will be deleted from the voicemailbox
(after having been emailed). Provides functionality that allows a user
to receive their voicemail via email alone, rather than having the
voicemail able to be retrieved from the Webinterface or the Extension
CAUTION: You must have email attachment set to yes if you
don't want your voicemail system to email you a notification saying
'You have a voicemail' and then immediately delete the voicemail. Make sure you've fully tested voicemail-to-email before you turn this on. See Email Problems for hints.