So far in the course it seems that most people are struggling with managing the access lists (ACL). At first this seemed kind of advanced, but the theory surrounding were quite simple to understand. ACLs really just is another level of enforcing the AAA triad previously mentioned in my journal (here). You can use it to discriminate at many different types of criteria from the person trying to enter your network. Like our lecturer T. Drange explains it, its like a bouncer at the door at the club reading a list of names of who can come in and not. This list can not only be the name of the person, but also how they should be dressed, can not be too drunk and so forth. As a former security guard this is something I could relate to easily.
And whilst some clubs only have a list of names, some other clubs are more strict on who they let inside – and have the aforementioned additional criteria on their list. This is also the difference between a Standard ACL (STA-ACL) and an Extended ACL (EXT-ACL). Apart from that they have their very own range of identifiable numbers (STA=1-99 and 1300-1999 / EXT=100-199 and 2000-2699) an EXT-ACL can be configured with a wide variety of discriminations (protocol, source, destination, ports and so on) that the STA-ACL can not.