Re: ADSL vs Leased line

Re: ADSL vs Leased line

[Florian Weimer]

John Bradford <john@grabjohn.com> writes:

> A leased line is guaranteed bandwidth,

Not at all.  Welcome to the wonderful world of ATM Traffic Management.

[DEFINITELY OFF-TOPIC] Re: ADSL vs Leased line

[Henning P. Schmiedehausen]

Florian Weimer <fw@deneb.enyo.de> writes:

>John Bradford <john@grabjohn.com> writes:

>> A leased line is guaranteed bandwidth,

>Not at all.  Welcome to the wonderful world of ATM Traffic Management.

That's the very point John was trying to make. A leased line in the
classic sense (E1/T1/ISDN) _is_ guranteed bandwith. You get 64k, 128k,
1920k, 1984k 2048k [1] guranteed, fixed bandwith synched with a master
clock.

And: bandwidth on a leased line != IP bandwidth. And with DSL lines
(which are either HDLC over copper (e.g. Lucent HST-DST) or simply
ATM-25 over copper (Cisco 14xx / Lucent Cellpipes) you can even get
both.

So your "wonderful world of ATM traffic management" is only correct
for some flavours of DSL lines.

	Regards
		Henning

Let's kill this thread. :-)

[1] 1920k = 1 slot for network management,
            1 slot for connection management, 
            30 channels data
    1984k = 1 slot for connection management,
            31 channels data (G.704)
    2048k = 32 channels data (G.703)

    A least in Germany, a "2 MBit leased line" can come in any of
    these flavours.

-- 
Dipl.-Inf. (Univ.) Henning P. Schmiedehausen          INTERMETA GmbH
hps@intermeta.de        +49 9131 50 654 0   http://www.intermeta.de/

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