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DCE Clockrate 8000000 ?

Understand from CISCO that the recommended rate for serial is 2000000. I have a back-to-back serial conx & when I place a '?' at the suffix after 'clock rate', I observe a few options with clock rate 8000000. Is it ok to assign the clock rate to 8000000 & what is/are the possible implications ? Another thought is, why CISCO permit 8000000 if it is not used for implementation ? Appreciate your thoughts & info sharing.



Re: DCE Clockrate 8000000 ?

The clock rate command does show values upto 8000000.

But the speed at the which data will be send, depends again on,

1. cable length

2. for eia/tia-232 the speeds above 148kbps are too fast for the interface. Its recommended to use the 232 for speeds upto 64000. For speeds above this, its recommended to use eia/tia-449 or v.35

3.Except on the 7xxx series which take serial port adapters, all other routers, need a clock value which is standard, like 1200, 2400.....etc...while on the 7xxx we can enter a non standard clock value like 1234234 etc.


Re: DCE Clockrate 8000000 ?

This only show up on certain platforms. The original serial controllers in the 2500 serioes for example can only do up to 2Mbs, but some of the newer controllers can do up to 8Mbs. If both sides can handle the speed, give it a whirl...