Polycom SIP 3.1 Administrator's Manual page 263

Attribute
reg.x.lineKeys
reg.x.callsPerLineKey
reg.x.bargeInEnabled
reg.x.outboundProxy.address
reg.x.outboundProxy.port
Permitted
Values Default
1 to max 1
1 to 34 OR 24 OR
1 to 24 OR 8
1 to 8
0, 1 Null
dotted-decimal IP Null
address or host
name
1 to 65535 5060
Interpretation
max = the number of line keys on the phone.
max = 1 on SoundStation IP 4000, 6000,
7000,
max = 2 on IP 301, 320, 330, 430,
max = 3 on IP 501,
max = 4 on IP 550, 560,
max = 6 on IP 600,
max = 48 on IP 601, 650, 670 (without any
Expansion Modules attached, only 6 line keys
are available)
The number of line keys on the phone to be
associated with registration 'x'.
For the SoundPoint IP 650 and 670, the
permitted range is 1 to 34 and the default is
34.
For the SoundPoint IP 550, 560, 600, and
601, the permitted range is 1 to 24 and the
default is 24.
For all other phones the permitted range is 1
to 8 and the default is 8.
This is the number of calls or conferences
which may be active or on hold per line key
associated with this registration.
Note that this overrides
call.callsPerLineKey for this registration.
Refer to Call Handling Configuration <call/>
on page A-64.
Note: A call active on another phone on a
shared line counts as a call for every phone
sharing that registration.
Allow remote user of SCA to interrupt call.
(Works in a similar way to resume.)
If set to 1, barge-in is enabled for line x.
If set to 0 or Null, barge-in is disabled for line
x.
IP address or host name and port of a SIP
server to which the phone shall send all
requests.
Configuration Files
A - 109