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ssh vs telnet - which is faster?

  [ Long mail , but interesting stuff. I'll put the question first here ,
and then a whole 2 pages of explanations/details/reasoning and then the
question once again ]

*  *  *  *
Question : ssh + compression is "faster" than telnet over ppp while telnet
is "faster" then ssh + compression over eth0 [ local network - *not* with
ISP ]  ... why ?
*  *  *  *


  I have this fundamental question , over the difference between ssh and
telnet .
  I can do a ....
        $ ssh -v -C -o CompressionLevel=9 symonds.net -l ravi
  and it would open an ssh connection with symonds.net and login 'ravi'
and in the verbose mode , with option CompressionLevel set to maximum ,
(9) . 
  and i can also try a 
        $ telnet symonds.net

  and it is more than obvious that ssh *WITH COMPRESSION* [ very important
that compression has to be used ] is "faster" than telnet ... 
  what I mean by "faster" is... transfer is obviously faster ... and I can
visually "see" things happening faster than it happens on a telnet.
  Now of course symonds.net blocks telnet ... so if you tried it , it
wouldn't work and you might think i'm pulling a lot of yarn ... but no...
i tried it out when it *did* allow telnet access. ;-)

  and for your reference , this is what I get when i logout of an ssh with
symonds.net ....
  *    *    *    *    *
$ logout
Connection to symonds.net closed.
rockford.myip.org: Transferred: stdin 16, stdout 1852, stderr 35 bytes in
rockford.myip.org: Bytes per second: stdin 0.1, stdout 6.8, stderr 0.1
rockford.myip.org: Exit status 0
rockford.myip.org: compress outgoing: raw data 233, compressed 211, factor
rockford.myip.org: compress incoming: raw data 1988, compressed 1328,
factor 0.67
 *   *    *   *    *   *

and if you're wondering what rockford.myip.org is , its my box.

  now , another thing is very obvious too ... ssh *WITHOUT COMPRESSION* is
"slower" than telnet ... [ over ppp ] 

  of course ...until now , i'm referring to both ssh and telnet over ppp

  Now comes the fun part... I tried all this over eth0 ... a local network
of 3 boxen , all running debian GNU/linux 2.1 (slink) . and now there is a
very very interesting observation .... ssh + compression [ probably more
secure etc since it supports encryption ] is *WAY* "slower" than a telnet
... what gives?

  This is very true , and you might trouble yourself to check it out if
you think i'm pulling your leg ;-)

  Now this beat me... I suppose its some networking fundas , which I badly
lack ...  and the only reason I could think up was , the compression over
eth0 bottlenecks because of the insanely high speeds over eth0 as compared
to ppp .... 

  Thats only a wild guess , and with *no* reasoning... 

  If you can think up a better reason as to why the behaviour is so funky
, [ I'm *SURE* there is some obvious reason that I've missed out somewhere
] ... mail the list ...


  And just in case all my ranting has been off course and digressed from
the actual question.... here it is again :

*  *  *  *
Question : ssh + compression is "faster" than telnet over ppp while telnet
is "faster" then ssh + compression over eth0 [ local network - *not* with
ISP ]  ... why ?
*  *  *  *

  Thanks for your time.


- Ravi.  


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