This completely stops traffic from 172.16.40.0 from getting out Ethernet 1. It has no effect on the
hosts from the Sales LAN accessing the Marketing LAN and the Internet since traffic to those
destinations doesn’t go through interface E1. Any packet trying to exit out E1 will have to go
through the access list first. If there were an inbound list placed on E0, then any packet trying to
enter interface E0 would have to go through the access list before being routed to an exit
interface.
//Let’s take a look at another example of a standard access list. Figure 7.2 shows an internetwork
of two routers with three LANs and one serial WAN connection.
You want to stop the Accounting users from accessing the Human Resources server attached to
the Lab_B router but allow all other users’ access to that LAN. What standard access list would
you create and where would you place it?
//The real answer is that you should use an extended access list and place it closest to the source,
but the question specifies that you should use a standard access list. Standard access lists, by rule
of thumb, are placed closest to the destination—in this example, Ethernet 0 outbound on the
Lab_B router. Here is the access list that should be placed on the Lab_B router: