Saturday, April 14, 2012

Arp cache aging time

Cisco routers
    4 hours
Cisco switches
    5 min
Windows Server 2003 and before
    2 min ( 10 min, if the address is reused )
Windows Vista and after
    Between 15 sec and 45 sec (random)
Linux box
    Various aging time

Switches are able to learn destination MAC addresses from client stations' arp request/query (because switches have longer aging time than client hosts). Those time differences keep them from flooding.

Refferences for Windows box
View the Address Resolution Protocol (ARP) cache

Description of Address Resolution Protocol (ARP) caching behavior in Windows Vista TCP/IP implementations