Administering Telephone Options
74 Avaya 1600 Series IP Deskphones Administrator Guide
has absolute authority. Otherwise, you can set VLAN tagging manually, by DHCP, or in the
46xxsettings.txt file.
If VLAN tagging is enabled (L2Q=0 or 1), the 1600 Series IP Telephones set the VLAN ID to
L2QVLAN, and VLAN priority for packets from the telephone to L2QAUD for audio packets and
L2QSIG for signalling packets. The default value (6) for these parameters is the recommended
value for voice traffic in IEEE 802.1D.
Regardless of the tagging setting, a 1600 Series IP Telephone will always transmit packets from
the telephone at absolute priority over packets from secondary Ethernet. The priority settings
are useful only if the downstream equipment is administered to give the voice LAN priority.
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).
If you do not want the default VLAN to be used for voice traffic:
●Ensure that the switch configuration lets frames tagged by the 1600 Series IP Telephone
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 1600 IP Series Telephone waits for a DHCPOFFER message when using a
non-zero VLAN ID. The VLANTEST default is “60” seconds. Using VLANTEST ensures that the
telephone 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 telephone restarts for
any reason and the VLANTEST time limit expires, the telephone assumes the administered
VLAN ID is invalid. The telephone 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 telephone does not return to the default VLAN.
Note:
Note: If the telephone returns to the default VLAN but must be put back on the
L2QVLAN VLAN ID, you must Reset the telephone. See the Reset procedure in
the Avaya 1600 Series IP Deskphones Installation and Maintenance Guide.