said by cramer: said by flq06:
layer 2 (only) switches doesn't keep any ARP info.
Yes they do; you just cannot see it on an unmanaged switch.
Layer-2 switch has no knowledge of IP address or anything concerning Layer-3 and up since Layer-2 switch deals with only MAC addresses. Therefore Layer-2 switch maintains CAM or MAC address table which correlate between MAC address and certain switch port. ARP Table keeps correlation between IP address and MAC address which typically Layer-3 capable devices maintain such as Layer-3 switch and router.
An exception is IGMP snooping feature where Layer-2 switch is capable to snoop Layer-3 info of Multicast group in order to associate the Multicast MAC address (as a result of the Multicast group translation from Layer-3 IP address to Layer-2 MAC address) with certain switch ports where the Multicast subscribers connect.
said by cramer:
Unless it's flooding every packet to every port all the time (which would make it a HUB), it does have tables of MAC's known to be on each port.
Layer-2 switches typically do not flood packets, however they flood frames since the switches only talk Layer-2.