[comp.sys.mac] TeleCommunications

fleabag@athena.mit.edu (Jeff Bellsey) (02/08/89)

While people seem to be talking quite a bit about better methods of 
file transmission, and the different protocols, I though I would ask
a (beginner's) question ---  which protocol is fastest?  That is, if
all I'm doing is simple standard uploading of BinHex'ed files, can (or
should) I use any protocol other than 'text' ?   Is Xmodem faster?

thanks in advance...
:bags
fleabag@athena.mit.edu

macak@lakesys.UUCP (James Macak) (02/09/89)

In article <9149@bloom-beacon.MIT.EDU> fleabag@athena.mit.edu (Jeff Bellsey) writes:
>While people seem to be talking quite a bit about better methods of 
>file transmission, and the different protocols, I though I would ask
>a (beginner's) question ---  which protocol is fastest?  That is, if
>all I'm doing is simple standard uploading of BinHex'ed files, can (or
>should) I use any protocol other than 'text' ?   Is Xmodem faster?

Although a straight text dump will be the quickest way to send/receive a
BinHexed file, you are taking a bit of a risk in performing the transfer this
way.  Since there is no error checking in this sort of info transfer, the
BinHexed file might pick up a glitch and you would never know it... until you
tried to unBinHex it, that is.  At that point you would get an error message
and the unBinHexing would fail.  Even one changed character in the file will
blow the whole BinHexed file.

So, it's best to use an error checking protocol.  ZModem would seem to be the
quickest of the protocols commonly available.  The Shareware program "ZTerm"
finally offers this protocol for Mac users.

Next in line would be 1K Y-Modem and X-Modem, and finally the original XModem
using 128 byte blocks.  Depending on your telecommunications program, there
may not be a huge diference between the file transfer rates of these X and Y
protocols.

So, to summarize, though a "text" transfer may be faster than the others,
since data integrity is not assured, it is more desirable to use an error
checking protocol.

Hope this helps.

Jim

-- 

Jim Macak  <lakesys!macak@csd1.milw.wisc.edu>