Re: Suggestions for custom application-layer protocol?

From: Grant Edwards (grante_at_visi.com)
Date: 05/27/05 

Date: Fri, 27 May 2005 00:04:16 -0000

On 2005-05-26, Mark <mark_2811nospam@excite.com> wrote:

> I expect I will end up with a text-based protocol, with a header
> that indicates the number of bytes in the payload.

If you're using a text-based protocol, you don't nead a header
with a payload count to tell you where the message ends. Use
an end-of-message character or string. The cr/lf pair is used
as the end-of-message delimiter by a lot of text-based
runs-on-top of TCP protocols. That approach works wonderfully
with line-oriented high-level text-handling libraries and
utilties -- you can do all sorts of useful stuff using nothing
but a few utilities like netcat, expect, and so on.

I've also seen protocols that use STX/ETX to frame messages,
and that works nicely as well, but isn't as compatible with
pre-existing utilities.

> The payloads will be composed of field=value pairs.

That Sounds like a good plan.

> Thanks guys I really appreciate it, this discussion has helped
> me out a great deal! 

-- 
Grant Edwards                   grante             Yow!  Hey, LOOK!! A pair of
                                  at               SIZE 9 CAPRI PANTS!! They
                               visi.com            probably belong to SAMMY
                                                   DAVIS, JR.!!

Relevant Pages

  • Re: Suggestions for custom application-layer protocol?
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