Enhanced Vlan Tagging - Nortel 2001 Installation And Operation Manual

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Enhanced VLAN Tagging

553-3001-368 Standard 7.00
Appendix B: 802.1Q VLAN description
4 The telephone rejects the DCHP offer (accepts it but immediately gives
up the lease).
5 The telephone reboots and sends a DHCP Discovery Request with the
first VLAN ID from the saved list. This is repeated for each VLAN ID in
the list until a response is received.
This works because the Layer 2 switch discards every DHCP Discovery
Request it receives from the IP Phone if the VLAN ID does not match the
VLAN IDs configured on the port. When the IP Phone sends a DHCP
Discovery Request with the port's configured VLAN ID, the packet passes
into the network and the DHCP server's Ack message is passed back.
Appendix A:When a DHCP Ack message is received, the IP Phone accepts
the offer and saves the IP address and Node IP address.
CS 1000 Release 4.5 introduces Enhanced VLAN, which has two main
functions:
• Enhance the current Voice VLAN by implementing the hardware VLAN
filter on the IP Phone port (SMP).
• Use TX High Priority Queue (HPQ) and 802.1P VLAN priority to
enhance the traffic control on the IP Phone and PC network interface.
August 2005