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Mac address aging
There is a field in MAC address table used to put the entry’s Age time which
determines how long a MAC entry can reside in a switch. The age time is refreshed
when a packet with that SA arrives. Usually, the age time is programmable.
Transmission schedule
In most layer 2 switches, the QoS is supported. QoS in a switch must
associate a transmission schedule to transmit the packet. This function is much to
do with the priority level that a packet has. With a given priority, the scheduler will
do the proper action on it. The scheduler has many ways to implement, and
different chips may support different schedule algorithms. Most common schedulers
are:
FCFS: First Come First Service.
Strictly Priority: All High before Low.
Weighted Round Robin:
Set a weight figure to the packet with a priority level, say 5-7, and next, set
another weight to the packet with a priority level, say 2-4 and so on. The WRR will
transmit the packet with the weight. So the packet of each priority level can be
allocated within a fixed bandwidth.
Bandwidth rating
Bandwidth rating is the limitation set by administrator, and it can be applied
to those with SLA. Bandwidth rating can be total bandwidth, types of service of a
port with many steps. The switch supports by-port Ingress and Egress total
bandwidth rate control capacity. The bandwidth rate resolution is 0.1 Mbps
(100Kbps) and ranges from 0 to 100Mbps.