Information Technology Reference
In-Depth Information
So, the calling number (CGN) is the number of the call originator, the forwarding number is the number of the extension that
forwarded the call to voicemail, and the called number is (in this example) the voicemail system.
Therefore, based on
Figure 5-1
and the configuration example given previously, the command
pattern ext-to-ext busy # FDN #2
would cause 955512345678 to be dialed and the DTMF pattern #1002#2 to be sent when extension 1002 is called from an internal
extension but it is busy. The number 955512345678 is the voicemail system number configured using the
voicemail
command, and
DTMF digit patterns (tones) corresponding to #1002#2 are played to the voicemail system when it answers; this causes the voicemail
system to route the call directly to the mailbox corresponding to extension 1002 and play the appropriate greeting. The precise DTMF
digit patterns that are required depend on the voicemail system.
Note that the command
pattern direct * CGN
would cause 955512345678*1002 to be dialed if the Messages button was pressed on
the phone corresponding to extension 1002. (There is no forwarding number in this case.)
Call Transfer
SRST routers support call transfer between Cisco IP phones that are registered with them by default. However, if call transfer to other
destinations is required, the following two commands are required:
■
transfer-pattern:
Specifies the destination phone numbers to which Cisco IP phones are allowed to transfer calls
■
transfer-system:
Configures the method used for call transfer
The following keywords can be used with the
transfer-system
command to configure the call transfer method:
■
blind:
When using this Cisco proprietary method, calls are transferred without the transferor first connecting to the
destination. This method is not recommended. (
full-blind
or
full-consult
are recommended instead.)
■
full-blind:
This specifies the H.450.2 standard for call transfer. Again, calls are transferred without the transferor first
connecting to the destination.
■
full-consult:
This again specifies the H.450.2 standard for call transfer but in this case, calls are transferred with the
transferor first connecting to the destination. Two lines are required for this type of call transfer, and if a second line is not
available, the
full-blind
method is used instead.
