NEC Electra Elite IPK Programming Manual page 776

Electra Elite IPK
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Programming Manual
VLAN Mode Selection (Memory Block 1-16-04)
Use this Memory Block to specify whether or not IEEE 802.1q VLAN Tagging
is enabled for each HUB(8)-U( ) ETU. This Memory Block must also be
enabled to use IEEE 802.p Priority. Priority options can be enabled in
Memory Block 1-16-06 (Port Based Priority Selection), Memory Block 1-16-07
(High Priority RX Tag Threshold), Memory Block 1-16-08 (High Priority TX
Tag Assignment), and Memory Block 1-16-09 (Low Priority TX Tag
Assignment).
Default VLAN ID Tag Insertion Assignment (Memory Block 1-16-05)
Use this Memory Block to insert VLAN ID tagging to data frames from network
devices that cannot insert VLAN tags. When data without a VLAN tag is
transmitted by the device on the port, a tag is inserted with the VLAN ID
assigned by this Memory Block.
Port Based Priority Selection (Memory Block 1-16-06)
Use this memory block to specify how frames, reaching the ingress port
without VLAN tags are marked for queuing internally in the HUB(8). The
HUB(8) has two queues: High Priority and Low Priority. When the frame
reaches the egress port, settings for Memory Blocks 1-16-08 (for High Priority
frames) and 1-16-09 (for Low Priority frames) for the egress port are used to
convert the low or high priority queue to a VLAN tag priority (0~7). Set to NO
(default), this Memory block does not mark frames for either queue; Memory
Block 1-16-07 then determines the priority queue for where the frame is sent.
High Priority RX Tag Threshold (Memory Block 1-16-07)
The HUB(8) has two queues: High Priority and Low Priority. When Memory
Block 1-16-06 is set to NO, and the priority of the VLAN tag is equal to or
greater than the setting in this block, the tag is queued for high priority.
Otherwise, it is queued for low priority. When it is transmitted out the egress
port of the HUB(8), it retains its original VLAN tag priority value.
High Priority TX Tag Assignment (Memory Block 1-16-08)
For frames marked at the ingress port by Memory Block 1-16-06 as High
Priority, this memory block setting on the egress port assigns a value (0 ~7) to
the priority field of the VLAN tag. The default is 7.
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