switches's address table size

[david90]

On newegg, I see "mac address table" size as one of the features of a switch. What is it and does the size of the mac address table effect performance? how?

 

[jmacavali]

The switch uses the table to know where to send packets of data. Every computer has a unique MAC address and the switch will record what port each MAC address is plugged into. It really doesn't effect performance enough to notice it. However, if it can hold more address than it has ports (an 8 port switch that holds 100 or whatever addresses) is because it can track a MAC address that may be hooked to another switch. This way it knows to send the data out port 8 (or whatever port the other switch is in) and it helps to speed traffic.

 

[david90]

The switch uses the table to know where to send packets of data. Every computer has a unique MAC address and the switch will record what port each MAC address is plugged into. It really doesn't effect performance enough to notice it. However, if it can hold more address than it has ports (an 8 port switch that holds 100 or whatever addresses) is because it can track a MAC address that may be hooked to another switch. This way it knows to send the data out port 8 (or whatever port the other switch is in) and it helps to speed traffic.

I saw an 8 port switch on newegg for about $20 and it has a 4K MAC address table. Isn't a 4k MAC address table overkill? Who is going to hook 500 switches together?

 

[jmacavali]

It maybe. However, the switch doesn't necissarily know what is hooked to it. It just knows that a certain MAC address is hooked up to port 8 or whatever. It could be across a whole network.

Really, I wouldn't get too worked up about the MAC address table. I don't even bother paying attention to them...