ACL's - my brain is not working.

My brain is dumb today. I can't remember how to determine which interface to apply an ACL on. Lets use this ACL as an example:

access-list 101 permit icmp any any
access-list 101 deny tcp any any eq 80

This would allow icmp to go through but block any web requests. Lets say I want this applied on the LAN intferace (Fa0/0). Is this inbound or outbound? My brain isn't working... lol.

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nice343

outbound on LAN

inbound on WAN

I undestood ACL by doing trial and error. Try doing that You will be suprised how easy it is to see the direction of where to apply the ACL

gojericho0

Think of inbound and outbound from the routers perspective:

Inbound on a LAN interface would be any LAN traffic going into that interface, outbound would be on the return trip or where the LAN is the destination.

The same thing would hold true for the WAN or serial links. Outbound on the serial link would be anything leaving the router out the serial interface. Inbound would be anything incoming on that serial interface

phantasm

Gotcha. Thanks again guys.

gojericho0

ICMP will pass, but TCP 80 will be dropped