Interface Commands
Interface configuration is one of the most fundamental aspects of getting a router online. There are many kinds of interfaces, corresponding to different physical media and lower-level protocols; some of the interface types are listed in Table 5-1. For the most part, each media type has its own configuration commands, although a few commands are common to all interfaces. The interface is where much of IP configuration takes place: it's where you set addresses and netmasks and specify how the interface interacts with the routing protocol you have chosen.
|
Type |
Description |
|---|---|
|
async |
Async lines are for modem dial-in and dial-out connections. The AUX port is an async line. Terminal servers have numerous async lines for modem connections. |
|
atm |
ATM (Asynchronous Transfer Mode) interfaces are used for connections to an ATM switch. This includes DSL connections. |
|
serial |
Serial ports are often connected to CSU/DSUs for point-to-point leased lines (56k, T1, etc.). |
|
ethernet |
Ethernet ports supporting 10 megabits/second. |
|
fastethernet |
Ethernet ports supporting 10 and 100 megabits/second. |
|
gigabitethernet |
Gigabit Ethernet ports supporting 10/100/1000 megabits/second. |
|
bri |
BRI (Basic Rate Interface) for ISDN (2B + D service). |
|
tokenring |
Token ring network interfaces. |
|
fddi |
Fiber Distributed Data Interconnect. |
|
hub |
A hub that is built into the router and treated as an interface. |
|
hssi |
High-Speed Serial Interface. Supports speeds up to 52 Mbps. |
|
loopback |
A virtual interface on the router. |
|
null |
Bit bucket interface. Anything sent to this interface is discarded. Used for simple route filtering. |
|
pos |
Packet over SONET interfaces. |
|
vlan |
Virtual LAN interfaces. |