I am preparing to take the CCNA exam and have been both hitting the books and searching wikipedia for some answers to some questions might be too basic to ask on serverfault, although I'm not sure.
I've spent more time than I'd like to admit trying to figure these out:
- (for the CCNA) does "T1", "T3" mean anything besides a speed? The books seems to only refer to it in regards to WANs, so is a T1 connection ever used for anything besides WANs? Do all the different WAN protocols (e.g. Frame Relay, ISDN, PPP, Cable, DSL, MPLS) belong to one of these classes, T1-T5?
- As I understand it, the reason we have a separate term "WAN" defined is because a "WAN" is physically different from a "LAN"; it spans a large distance, so it requires serial transimission protocols, (e.g. X.25) instead of Ethernet, is that correct? Is this why a Cisco router might have certain "interfaces" designated for FastEthernet connections and others for serial (WAN) connections?
- When we're talking about controllers, DCEs, DTEs, DSUs are we talking about the data link layer or physical layer?
- Why would WICs be necessary instead of a NIC?
Would any one of these questions be considered on-topic here? If these questions are not suitable for serverfault, where are they better directed? Cisco's community forums? Thanks for any help.