Aastra Telecom 57I CT, 55I, 53I manual Bridged Line Appearance BLA 55i, 57i, 57i CT only

IP Phone Administrator Guide Operational Features

Operational IP Phone Features

Bridged Line Appearance (BLA) (55i, 57i, 57i CT only)

A SIP bridge line appearance (BLA) on the IP phones allows multiple devices to share a single directory address (DA).

For example, people working at a technical support department could be located in different places. If their desktop phones are configured for BLA DA, when customer calls come in, all the phones with the BLA DA would ring but the call can only be answered by one of them.

Once the call is answered, the rest of the phones reflect the status of the call. If the call was put on "hold" by the original recipient, any one from the group can pick up the call.

Notes:

1. This feature is dependent on the IP telephony system to which the IP phone is registered and according to draft-anil-sipping-bla-02.txt.

2.Interactive Intelligence and Sylantro servers support the single BLA group with single line appearance feature only.

You can apply BLA on the IP phones as follows:

•As a single BLA group - One BLA DA is shared among multiple phones. Only one phone at a time can pick up an incoming call or initiate an outgoing call on the BLA DA. All phones reflect the usage of the BLA DA. If the call is put on "hold", any one from the group can pick up the "held" call.

•As a multiple BLA group - On one single phone, multiple BLA DA can be associated with different line appearances. Every BLA DA is independent from each other and follows the same rules as "a single BLA group".

•As multiple instances of a BLA DA - A "x-line-id" parameter was defined in draft-anil-sipping-bla-02.txtto present the incoming call to or place an outgoing call on the specified line appearance instance. The parameter is carried in "Alert-Info" header field over the request-URI (INVITE e.g.) or in the NOTIFY messages to report the status of a dialog.

BLA DA can be configured on a global basis or on a per-line basis on the IP phones using the Aastra Web UI or the configuration files.

5-144 41-001160-00, Release 2.1, Rev 04