Good day, To start off, I am new to Cisco and networking and am currently taking a course.  I configured an ACL, per our assignment, to accomplish what the task was, and it worked but was not the standard ACL configuration command that the instructor said we were to use; and I don't know why it worked.  Let me describe what's going on.  Here's the configuration of the lab: We have 12 computers.  Each computer is connected to its own 3750 and 2960.  Every pair of computers (1&2, 3&4, etc) is a "pod" which connects together to a LAN.  6 separate LANs connect together to a single 3750.  Say we give the WAN an IP address of 187.149.150.X (where X is the computer number: 1-12). The task is to configure the ACL to allow telnet in the port range 22 - 23.  I am computer 2 and need to access computer 4, while computer 12 needs to access me at computer 2 (repeat for all computers this pattern).  I should enter the following into the console for my 3750: permit tcp host 187.149.150.12 any range 22 23 permit tcp host 187.149.150.4 any range 22 23 established I did not enter this.  Instead, I entered: permit tcp host 187.149.150.12 any range 22 23 permit tcp 187.149.150.4 187.149.150.2 any range 22 23 established When I displayed my ACL, it changed 187.149.150.4 to 0.0.0.4 so it read: 30 permit tcp 0.0.0.4 187.149.150.2 any range 22 23 telnet My questions are why does my ACL work?  And does this open any problems up, besides the fact that it's telnet? From what I am understanding is it used the second IP address given as a wildcard and defaulted the first address to 0.0.0.4, and now it allows all TCP connections on ports 22-23 from 0.0.0.4 to 187.149.150.6 that are established by my IP address which is why I was able to connect to 187.149.150.4 via telnet.  Is this correct?   Thanks in advance! ... View more