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RE: WAN - serial link and RS-232 serial link [7:41670] posted 04/17/2002
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>I got my numbers from Cisco's Internetworking Terms and Acronyms (not
>that  Cisco is always right ;-) It says RS-232 was limited to 64 Kbps and
>that RS 449 is 2 Mbps.
>
>Here what that document says about RS-530:
>
>Refers to two electrical implementations of EIA/TIA-449: RS-422 (for
>balanced transmission) and RS-423 (for unbalanced transmission).

Here's a bit of the history.

RS-232 specified electrical, mechanical, and logical aspects of the 
interface. X.21 bis is _almost_ identical.

The next generation split up the electrical and mechanical:
    RS-422  relatively high speed, short-range, balanced
    RS-423  shorter unbalanced, longer range, lower speed, easily
interoperates
            with RS-232 electrical (well, with a resistor)
    RS-449  37-pin mechanical connector
    (No RS- but ISO-number) 15-pin connector originally used for X.21.

RS-530 cleaned up the act.

>
>I don't think the actual numbers matter to answer the fellow's question.
>The bottom line is that serial doesn't mean slow.

OC-768 isn't slow!

-- 
"What Problem are you trying to solve?"
***send Cisco questions to the list, so all can benefit -- not 
directly to me***
********************************************************************************
Howard C. Berkowitz      hcb@xxxxxxxxxxxx
Chief Technology Officer, GettLab/Gett Communications http://www.gettlabs.com
Technical Director, CertificationZone.com http://www.certificationzone.com
"retired" Certified Cisco Systems Instructor (CID) #93005




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