Ip Phone Support - Nortel 1110 Installation And Operation Manual

IP Phone support

Appendix B: 802.1Q VLAN description
field is the Tag Protocol Identifier containing 8100 (hex), allowing the
Ethernet interface to distinguish it from standard Ethernet frames. The last 16
bits of the 802.1Q tag contain the following information:
• a 3-bit Priority field (the 802.1p defined bits)
• a 1-bit Canonical Field Identifier (CFI)
• a 12-bit VLAN ID field
The IP Phones support 802.1Q as follows:
• 802.1Q can be enabled or disabled at boot time using manual
configuration or control downloaded from the TPS.
• If 802.1Q is disabled, standard Ethernet frames are transmitted.
• If 802.1Q is enabled, all frames transmitted by the Ethernet driver have
the 802.1Q tag bytes inserted between the source MAC address and the
protocol type field. The tag protocol identifier field contains 8100 (hex)
and the CFI bit is set to 0.
• When 802.1Q is enabled, the configuration of separate voice and data
VLANs is possible. Each VLAN has its own ID and priority on the IP
Phone. Voice messages have the priority bits of all frames set to 6 (octal)
and the VOICE VLAN ID is set to 000 (hex) by default. Data messages
have the priority bits of all frames set to 0 and the DATA VLAN ID is
set to 000 (hex) by default. The GUI and TPS configured values override
these values.
• The IP Phone Ethernet driver receives any Ethernet frame destined for it,
regardless of whether 802.1Q is enabled or whether the received frame is
an 802.1Q tagged frame.
Note: The only exception is any 802.1Q tagged frame with the CFI = 1.
In this case the frame is discarded.
• The IP Phone Ethernet driver strips the 802.1Q tag information from the
frame prior to passing it on to the IP stack.
• The IP Phone Ethernet driver filters packets by the VLAN tag and MAC
address. Tagged traffic is prioritized and routed based on the priority bits.
IP Phones Description, Installation, and Operation
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