Subject: [Dots] Achieving smaller DOTS messaging through compression

From: Robert Moskowitz <[email-masked]>
Date: Wed, 9 Mar 2016 09:48:51 -0500

XML for DOTS messages seems to be in a couple proposals.  Yet XML is 
often dragged out as a bad player in constrained communications (look at 
CoAP as an example of avoiding XML).

Almost 20 years ago IPCOMP (currently RFC 3173) was done for IPsec and 
some interesting analyses back then showed that it really helps.

If DOTS secure communications mechanism is IPsec, then IPCOMP is 
automatically an available option for implementors.  IKEv2IANA provides:

http://www.iana.org/assignments/ikev2-parameters/ikev2-parameters.xhtml#ikev2-parameters-17

Value     Compression Type     Reference
0         Reserved             [RFC7296]
1         IPCOMP_OUI           [RFC7296]
2         IPCOMP_DEFLATE       [RFC2394]
3         IPCOMP_LZS           [RFC2395]
4         IPCOMP_LZJH          [RFC3051]
5-240     Unassigned
241-255   Private use          [RFC7296]

I am not aware of a compression option for TLS or DTLS.  If it exists, 
can someone point me to the information on it.

Thus I am thinking about a Generic Protocol Compression document on how 
to effectively do compression within any security wrapper that can 
negotiate the inclusion of a GPCOMP option.

Potentially it would only take one bit from a header to say if this 
envelope content is compressed using the compression algorithm 
negotiated for this Security Association (unlike the 4 bytes of 
IPCOMP).  Or it could use the same format as IPCOMP...

Does anyone (particularly anyone using XML) have any experience to offer?

---

From: Robert Moskowitz <[email-masked]>
Date: Thu, 10 Mar 2016 15:15:52 -0500

I have learned a few things about TLS compression.  Basically it is a 
problem.  And a problem that ESP with IPCOMP would not have.  Or SSE 
with a GPCOMP option.  But NOT an XML compress object.

On 03/09/2016 09:48 AM, Robert Moskowitz wrote:
> often dragged out as a bad player in constrained communications (look 
> at CoAP as an example of avoiding XML).
>
> Thus I am thinking about a Generic Protocol Compression document on 
> how to effectively do compression within any security wrapper that can 
> _______________________________________________
> Dots mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/dots
>