[comp.sys.mac.comm] Kermit and MNP5

gandrews@netcom.COM (Greg Andrews) (04/06/91)

In article <1991Apr5.145642.3715@ux1.cso.uiuc.edu> dorner@pequod.cso.uiuc.edu (Steve Dorner) writes:
>
>Kermit uses 7-bit data, right?  MNP-5 would help on such transfers.
>

Kermit wouldn't do any better.  Sure it encodes the data into printable
characters, but that doesn't make the data redundant.

If the data was already compressed, the character patterns can't be
compressed further.  No matter how you re-code the data bytes, the
*patterns* can't be compressed.  Using Kermit won't help you get
better throughput over MNP5 links.


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|  Greg Andrews   |       UUCP: {apple,amdahl,claris}!netcom!gandrews    |
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dorner@pequod.cso.uiuc.edu (Steve Dorner) (04/08/91)

>>Kermit uses 7-bit data, right?  MNP-5 would help on such transfers.
>Kermit wouldn't do any better.  Sure it encodes the data into printable
>characters, but that doesn't make the data redundant.

Yes, it does increase redundancy, by wasting 1/8 of the bandwidth of the
connection with 0 bits.  MNP5 could (in theory) squeeze that 1/8 back out.

>Using Kermit won't help you get
>better throughput over MNP5 links.

No, but using MNP 5 can take some of the penalty out of using Kermit,
which is what I said.
--
Steve Dorner, U of Illinois Computing Services Office
Internet: s-dorner@uiuc.edu  UUCP: uunet!uiucuxc!uiuc.edu!s-dorner