Velocity Reviews

Velocity Reviews (http://www.velocityreviews.com/forums/index.php)
-   Cisco (http://www.velocityreviews.com/forums/f27-cisco.html)
-   -   FTP vs TFTP (http://www.velocityreviews.com/forums/t34957-ftp-vs-tftp.html)

JR 08-15-2004 07:10 PM

FTP vs TFTP
 
Greetings all,

I know that FTP rides on TCP (connection-oriented, reliable) and that TFTP
rides on UDP (connectionless, unreliable). To me this means that the TCP
session used for FTP conducts a three-way handshake, uses variable
windowing, and acknowledges all packet receipt. I'm assuming that the UDP
session for TFTP does not have acknowledgement or windowing.

This in mind, all conditions being the same except for the use of FTP or
TFTP; why would it take longer to transfer a file using TFTP than it would
for that same file with FTP?

To this point I have been told that the TFTP actually DOES use
acknowledgements and that the difference is that it does not have the
capability to use windowing. I'm not quite convinced that this is correct.
Everything I can find states that UDP does not acknowledge. I have not
actually found anything that states that TFTP does not use some sort of
"unreliable" acknowledgement, but I know that it rides on UDP, therefore my
conclusion is that there is no acknowledgement associated with TFTP.

Does anybody have any information to the contrary, or any evidence that
supports either side of this discussion?

TIA,
JR



Mirko Kulpa 08-15-2004 07:24 PM

Re: FTP vs TFTP
 
JR wrote:
> Greetings all,
>
> I know that FTP rides on TCP (connection-oriented, reliable) and that TFTP
> rides on UDP (connectionless, unreliable). To me this means that the TCP
> session used for FTP conducts a three-way handshake, uses variable
> windowing, and acknowledges all packet receipt. I'm assuming that the UDP
> session for TFTP does not have acknowledgement or windowing.
>
> This in mind, all conditions being the same except for the use of FTP or
> TFTP; why would it take longer to transfer a file using TFTP than it would
> for that same file with FTP?


TFTP uses a stop-and-wait-protocol an a maximum packet size of 512
bytes. It sends 512 bytes and wait for the ack.
FTP uses sliding windows ans bigger packets.

So FTP is faster, especially on links with a high RTT-


Mirko
--
http://uridium.net/net/guide2na - Fehlersuche in Netzwerken

Leon McCalla 08-16-2004 03:32 AM

Re: FTP vs TFTP
 
Think of it this way....
your HTTP browser request a web page at layer 4 level and TCP/IP takes care
of delivery and acknowledgements. The end result is that you get a fast
stream of data. (FTP is similar to this)

TFTP requests one packet at a time similarly to the way that a command line
ping waits for a reply before sending a second packet. The end result is a
slow back and forth process. (it is possible to stream UDP data the way
real-audio does but that is not what TFTP does)

TFTP is a trade of transfer speed for simplicity and quick setup time. FTP
is good for large file transfers or transfering groups of files. TFTP is
usually used for loading hardware code on the fly. ie when routers are
booted or upgraded or also for audio prompts.

Leon
leonmccalla at hotmail.com




J R 08-19-2004 03:16 AM

Re: FTP vs TFTP
 
Thanks for the reply Mirko.

J R


"Mirko Kulpa" <spam.trap@kamp-dsl.de> wrote in message
news:2o9rk7F84vebU1@uni-berlin.de...
> JR wrote:
> > Greetings all,
> >
> > I know that FTP rides on TCP (connection-oriented, reliable) and that

TFTP
> > rides on UDP (connectionless, unreliable). To me this means that the TCP
> > session used for FTP conducts a three-way handshake, uses variable
> > windowing, and acknowledges all packet receipt. I'm assuming that the

UDP
> > session for TFTP does not have acknowledgement or windowing.
> >
> > This in mind, all conditions being the same except for the use of FTP or
> > TFTP; why would it take longer to transfer a file using TFTP than it

would
> > for that same file with FTP?

>
> TFTP uses a stop-and-wait-protocol an a maximum packet size of 512
> bytes. It sends 512 bytes and wait for the ack.
> FTP uses sliding windows ans bigger packets.
>
> So FTP is faster, especially on links with a high RTT-
>
>
> Mirko
> --
> http://uridium.net/net/guide2na - Fehlersuche in Netzwerken




J R 08-19-2004 03:18 AM

Re: FTP vs TFTP
 
"TFTP requests one packet at a time similarly to the way that a command line
ping waits for a reply before sending a second packet."

Good example, Leon. Thanks.

J R



mohit.nmims 02-16-2010 04:28 AM

but what is the difference in the application of ftp and tftp?

bryanpalacios 02-16-2010 04:56 AM

Quote:

Originally Posted by mohit.nmims
but what is the difference in the application of ftp and tftp?


i kinda see it this way

--- if you want to risk to get errors in your transefer u can use tftp
--- if u want a more reliable transfer u can use ftp...:driver:


All times are GMT. The time now is 12:21 AM.

Powered by vBulletin®. Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO ©2010, Crawlability, Inc.