I have a Cisco 827-4V ADSL router and I want to add an incoming ACL to the ADSL interface that will block attempts to spoof traffic from my network addresses (i.e. so someone outside my network cannot send a packet to a host on my network if the packet claims to be from another host on my network).
My network numbers look kinda like this (the last octet of the Broadcast and also the Netmask are the real numbers):
My router occupies 10.70.41.65
Would the correct ACL be --> access-list 123 deny ip 10.70.41.64 0.0.0.63