WAN link using ethernet?

I swear that I once saw a diagram (don't remember where now) where one router was connecting to another with no LANs between them, and the interfaces were fast ethernet. Is this done? I thought router-to-router connections were only serial interfaces if there were no LANs on the segment?

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Comments

Bill Kaster

AFAIK you can only connect routers via serial links, be they DB60, smart serial, etc. Actually, a better question for us nobs would be, do serial and ethernet links on a router all each have their own broadcast domain? All ports no matter what kind should all have their own broadcast domains on a router, right?

rossonieri#1

hi tricon7,

ya sure, why not? i mean why cant we use ethernet as WAN connection?
same as we use a cable modem right? that was ethernet too.
but nowadays - thereis a new name called metro-ethernet, faster line using fiber optic connectivity, and terminated in T1 or E1 speed.

so - basically, about WAN and LAN it is only how we see our network from user perspective. about its physical device connector - true that most of them using serial interface, but not today - you can use many kinds of interface like wireless and ethernet.

HTH.

r_durant

Bill Kaster wrote:

Actually, a better question for us nobs would be, do serial and ethernet links on a router all each have their own broadcast domain? All ports no matter what kind should all have their own broadcast domains on a router, right?

I would think the answer to this is yes, remember routers break up broadcast domains...so each ethernet (or virtual ethernet) port would create/separate broadcast domains...

However, I don't think serial point-to-point connections create a broadcast domain, but may be point-to-multipoint connections, someone can verify this...

APA

Serial will be Point-to-Point but you can multiplex the connection (split into various channels depending on the bandwitdh)

This then theoretically should be called a Point-to-Multipoint connection.