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Community Member

What or how define de real bandwitch

I know that the bandwitch command is use for QoS and protocols, so, what define the real bandwitch of one serial interface ?

What define that my router comunicate with other, in other city, with 2048Mbps ?

Hall of Fame Super Gold

What or how define de real bandwitch

The real bandwidth for a serial interface is determined by the clocking supplied for that circuit.



Community Member

What or how define de real bandwitch

Ok, this can be a "clock rate" or some QoS method ? Traffic Shaping, class map ...?

I dont know if u can understand me, but, how my router know the bandwitch of the other side (ISP) is providing ?

Sorry for my english :/

Hall of Fame Super Bronze

What or how define de real bandwitch

Your router won't know the bandwidth supplied by the ISP unless it's configured as such.

If you are subscribed to a sub-rated service, we recommend configuring QoS to avoid drops in the ISP side.

For instance, if you have a DS3 serial interface and you've only purchased half of that, the router will attempt to deliver up to 45Mbps and the ISP router will drop data over 22.5Mbps.

Hope this helps.


Super Bronze

Re: What or how define de real bandwitch


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I think serial interfaces will "pick up" the clock rate for their bandwidth.  If not, or on any interface where available end-to-end transit bandwidth is less than what the physical interface supports, the bandwidth statement will "inform" other "things" about the interface bandwidth (although it won't, by default, limit the interface's physical bandwidth).

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