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PVID
A Port VLAN Identifier is a classification mechanism that associates a port with
a specific VLAN and is used to make forwarding decisions for untagged packets
received by the port. For example, if port 2 is assigned a PVID of 3, then all
untagged packets received on port 2 will be assigned to VLAN 3. This number is
generally the same as the VID number assigned to the port in the Edit 802.1Q
VLANs window above.
GVRP
The Group VLAN Registration Protocol (GVRP) enables the port to dynamically
become a member of a VLAN. GVRP is disabled by default.
QoS
QoS settings allow customization of packet priority in order to facilitate delivery of data traffic that
might be affected by latency problems. The IEEE 802.1p Priority specification uses eight priority levels
to classify data packets. In 802.1p compliant devices, a tag inserted into the packet header is used to
identify the priority level of data packets.
The Switch implements 802.1p priority using eight hardware queues. Therefore, the Switch must have
a means of mapping the eight levels specified in the IEEE 802.1p standard to the eight hardware
queues used in the Switch. This is done using the Class of Service menu explained below. Further
customization of priority classification can be done with the Output Scheduling menu, also explained
below. Individual ports may still be assigned priority using the eight levels as defined by the 802.1p
standard. It is important to note that changes in a networks QoS scheme should be carefully consid-
ered, planned for and if possible tested for efficiency. When set up properly, it QoS can allow efficient
and timely delivery of data for video conferencing or IP telephony without causing unacceptable delays
of other network traffic. If QoS is not well set up however, significant delays and excessive packet loss
may result for data assigned to lower priority queues.
