Avaya one-X 1603SW, Administrator'S Manual, Page: 85 / 124

VLAN Considerations
Issue 1 June 2010 85
Note:
Note:
Regardless of the setting of L2Q, VLANTEST, or L2QVLAN, you must have
DHCP administered so that the telephone will get a response to a
DHCPDISCOVER when it makes that request on the default (0) VLAN.
After VLANTEST expires, if a 1603SW-I SIP IP Deskphone receives a non-zero
L2QVLAN value, the telephone will release the IP Address and send
DHCPDISCOVER on that VLAN. Any other release will require a manual reset
before the telephone will attempt to use a VLAN on which VLANTEST has
expired. See the Reset procedure in Chapter 3 of the
Avaya one-X™ Deskphone
Value Edition SIP for 1603SW-I Deskphones Installation and Maintenance Guide .
The telephone ignores any VLAN ID administered on the Communication
Manager call server.
VLAN Default Value and Priority Tagging
The system value L2QVLAN is initially set to “0” and identifies the 802.1Q VLAN Identifier. This
default value indicates “priority tagging” as defined in IEEE 802.IQ Section 9.3.2.3. Priority
tagging specifies that your network closet Ethernet switch automatically insert the switch port
default VLAN without changing the user priority of the frame (cf. IEEE 802.1P and 802.1Q).
The VLAN ID = 0 (zero) is used to associate priority-tagged frames to the port/native VLAN of
the ingress port of the switch. But some switches do not understand a VLAN ID of zero and
require frames tagged with a non-zero VLAN ID.
If you do not want the default VLAN to be used for voice traffic:
●
Ensure that the switch configuration lets frames tagged by the 1603SW-I SIP IP
Deskphone through without overwriting or removing them.
●
Set the system value L2QVLAN to the VLAN ID appropriate for your voice LAN.
Another system value you can administer is VLANTEST . VLANTEST defines the number of
seconds the 1603SW-I SIP IP Deskphone waits for a DHCPOFFER message when using a
non-zero VLAN ID. The VLANTEST default is “60” seconds. Using VLANTEST ensures that the
deskphone returns to the default VLAN if an invalid VLAN ID is administered or if the phone
moves to a port where the L2QVLAN value is invalid. The default value is long, allowing for the
scenario that a major power interruption is causing the phones to restart. Always allow time for
network routers, the DHCP servers, etc. to be returned to service. If the deskphone restarts for
any reason and the VLANTEST time limit expires, the telephone assumes the administered
VLAN ID is invalid. The deskphone then initiates registration with the default VLAN ID.
Setting VLANTEST to “ 0 ” has the special meaning of telling the phone to use a non-zero VLAN
indefinitely to attempt DHCP. In other words, the deskphone does not return to the default
VLAN.