ZyXEL Communications ES-3124 manual 79

	ES-3124 User’s Guide
Table 10 Switch Setup (continued)
LABEL	DESCRIPTION
Aging Time	Enter a time from 10 to 3000 seconds. This is how long all dynamically learned MAC
	addresses remain in the MAC address table before they age out (and must be
	relearned).
GARP Timer: Switches join VLANs by making a declaration. A declaration is made by issuing a Join
message using GARP. Declarations are withdrawn by issuing a Leave message. A Leave All message
terminates all registrations. GARP timers set declaration timeout values. See the chapter on VLAN
setup for more background information.
Join Timer	Join Timer sets the duration of the Join Period timer for GVRP in milliseconds. Each
	port has a Join Period timer. The allowed Join Time range is between 100 and
	65535 milliseconds; the default is 200 milliseconds. See the chapter on VLAN setup
	for more background information.
Leave Timer	Leave Time sets the duration of the Leave Period timer for GVRP in milliseconds.
	Each port has a single Leave Period timer. Leave Time must be two times larger
	than Join Timer; the default is 600 milliseconds.
Leave All Timer	Leave All Timer sets the duration of the Leave All Period timer for GVRP in
	milliseconds. Each port has a single Leave All Period timer. Leave All Timer must be
	larger than Leave Timer.

Priority Queue Assignment

IEEE 802.1p defines up to eight separate traffic types by inserting a tag into a MAC-layer frame that contains bits to define class of service. Frames without an explicit priority tag are given the default priority of the ingress port. Use the next two fields to configure the priority level-to-physical queue mapping.

The switch has eight physical queues that you can map to the 8 priority levels. On the switch, traffic assigned to higher index queues gets through faster while traffic in lower index queues is dropped if the network is congested.

Priority Level (The following descriptions are based on the traffic types defined in the IEEE 802.1d standard (which incorporates the 802.1p).

Level 7	Typically used for network control traffic such as router configuration messages.
Level 6	Typically used for voice traffic that is especially sensitive to jitter (jitter is the
	variations in delay).
Level 5	Typically used for video that consumes high bandwidth and is sensitive to jitter.
Level 4	Typically used for controlled load, latency-sensitive traffic such as SNA (Systems
	Network Architecture) transactions.
Level 3	Typically used for “excellent effort” or better than best effort and would include
	important business traffic that can tolerate some delay.
Level 2	This is for “spare bandwidth”.
Level 1	This is typically used for non-critical “background” traffic such as bulk transfers that
	are allowed but that should not affect other applications and users.
Level 0	Typically used for best-effort traffic.
Apply	Click Apply to save your changes to the switch’s run-time memory. The switch loses
	these changes if it is turned off or loses power, so use the Save link on the top
	navigation panel to save your changes to the non-volatile memory when you are
	done configuring.
Cancel	Click Cancel to reset the fields.

Chapter 7 Basic Setting 77