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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 the SA. 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 a packet has. With the
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: WRR
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 that
the packet of each priority level can be allocated 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.
