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Does serial clock rate influence bandwidth?

Discussion in 'Routing & Switching' started by Septima77, Sep 27, 2009.

  1. Septima77

    Septima77 Nibble Poster

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    For my home lab I am using a serial connection between two routers and I am always using the clockrate 64000 and bandwidth 64 commands on the DCE side.
    I know the bandwidth command does not actually set the band width but is used for communicating the bandwidth for routing and QoS purposes.
    My question is, if I set the clockrate in my simulated setup higher, does that mean I have a higher bandwidth on that interface?
     
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  2. craigie

    craigie Terabyte Poster

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    You are simulating a WAN Link by using a Serial DCE/DTE cable.

    The clock rate is set by the ISP, which you would do at the DCE end.

    So yes, the higher the clockrate, the better the connection. All of this was covered in the CCENT.

    According to your signature you have the CCNA and CCNA Security and therefore would already know the answer to this question.
     
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  3. r.h.lee

    r.h.lee Gigabyte Poster

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    Septima77,

    It depends. Is there a cable end plugged into the physical port that is associated with that interface?
     
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  4. Septima77

    Septima77 Nibble Poster

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    Eh? Yes! :D

    I have two wic-1T cards (on two different routers that is :rolleyes:) connected with a DB-60 DCE-DTE cross-over cable.

    I agree wityh craigie that I should know this, but... I can't find any proper info on simulated connections.

    My Sybex CCNA book by Lammle has exactly one sentence on this matter. (page 786)
    "....you need to provide clocking on the DCE end of the cable........". That's it.

    Articles that I found on the internet talked about clocking mismatches, but not the effect of clock rate on bandwidth. Still not sure what that impact is. Is it linear: clock rate 128000 corresponds to bandwidth 128?
     
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  5. danielno8

    danielno8 Gigabyte Poster

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    ^ yep
     
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  6. Rich165

    Rich165 Bit Poster

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    Hi,
    I wondered about the same thing a few weeks back, I just did a constant ping to the remote router from my host and changed the clock speed, just watch the ping change it's response times as you increase/decrease the clock on the DCE end.....almost magical:blink
     
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  7. cisco lab rat

    cisco lab rat Megabyte Poster

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    Clockrate affects the interface bit rate.

    Bandwidth is a measure of the width of a range of frequencies, measured in hertz

    Hate to be pedantic, but termz iz termz init!!
     
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