[mmox] Field names as numbers?

Catherine Pfeffer <cathypfeffer@gmail.com> Thu, 26 February 2009 13:59 UTC

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Date: Thu, 26 Feb 2009 14:59:22 +0100
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From: Catherine Pfeffer <cathypfeffer@gmail.com>
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Subject: [mmox] Field names as numbers?
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> Does the current binary encoding encode the actual names and types of
> properties before sending the values?

It does not encode them *before* sending them. It intermixes the data, the
data types and the field names. The data is always next to its type and next
to its name.

> If so, you could probably cut out
> at least half, if not more, using the separate schema method.

Yes we could. Yes it would be a significant bandwidth win.

I am not sure I like this idea of replacing keys like "Nose_Orientation"
with numbers like 443:
 - a protocol dump would be harder to debug (you'd need a table to know what
each field means).
 - it would be less simple in a program because you would need to look up in
a table to solve the indirections
 - it is error prone (it is easier to mix field 443 with field 442 than to
mix field "Nose_Orientation" with field "Associated_Sound")
 - if you have been unable to transmit the packet containing the table, you
can't do anything anymore
I have very bad memories of ISO 2709 (http://en.wikipedia.org/wiki/ISO_2709)
which also takes the "tags are numbers" approach.

But I realize the reasons above are somehow weak. With such a reasoning, we
would not use schemas with XML files either. Perhaps Infinity has better
arguments pro or against it.

-- 
Cathy