3Com 4500 PWR 26-Port Configuration Manual page 465

Meanings of the sub-options for Option 184
Table 39-1 Meanings of the sub-options for Option 184
Sub-option
NCP-IP
(sub-option 1)
AS-IP
(sub-option 2)
Voice VLAN
Configuration
(sub-option 3)
Fail-Over Call
Routing
(sub-option 4)
For the configurations specifying to add sub-option 2, sub-option 3, and sub-option 4 in the response
packets to take effect, you need to configure the DHCP server to add sub-option 1.
Feature
The NCP-IP sub-option
carries the IP address of
the network call processor
(NCP).
The AS-IP sub-option
carries the IP address of
the alternate server (AS).
The voice VLAN
configuration sub-option
carries the ID of the voice
VLAN and the flag
indicating whether the voice
VLAN identification function
is enabled.
The fail-over call routing
sub-option carries the IP
address for fail-over call
routing and the associated
dial number. The IP
address for fail-over call
routing and the dial number
in sub-option 4 of Option
184 refer to the IP address
and dial number of the
Session Initiation Protocol
(SIP) peer.
39-12
Function
The IP address of the
NCP server carried by
sub-option 1 of Option
184 is intended for
identifying the server
serving as the network
call controller and the
server used for
application
downloading.
The alternate NCP
server identified by
sub-option 2 of Option
184 acts as the backup
of the NCP server. The
NCP server specified
by this option is used
only when the IP
address carried by the
NCP-IP sub-option is
unreachable or invalid.
The sub-option 3 of
Option 184 comprises
two parts:
One part carries the
flag indicating
whether the voice
VLAN identification
function is enabled.
The other part
carries the ID of the
voice VLAN.
When the NCP server
is unreachable, a SIP
user can use the
configured IP address
and dial number of the
peer to establish a
connection and
communicate with the
peer SIP user.
Note
When used in Option
184, this sub-option
must be the first
sub-option, that is,
sub-option 1
The AS-IP sub-option
takes effect only when
sub-option 1 (that is,
the NCP-IP
sub-option) is defined
A flag value of 0
indicates that the
voice VLAN
identification
function is not
enabled, in which
case the
information carried
by the VLAN ID part
will be neglected.
A flag value of 1
indicates that the
voice VLAN
identification
function is enabled.
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