Subject: [core] #123: Etag size

From: "core issue tracker" <[email-masked]>
Date: Thu, 10 Mar 2011 13:52:07 -0000

#123: Etag size

 In November we had a discussion of the sizes of the two opaque strings we
 have (Etag and Token):
 http://www.ietf.org/mail-archive/web/core/current/msg01116.html

 We did adjust Token to be 1-8 bytes, but not Etag.  Even though they serve
 different purposes, this looks like an omission.  E.g. looking at HTTP
 mappers, it is clear that it is hard to do stateless mapping (hashing) of
 HTTP Etags to four bytes (birthday paradox).  Enabling up to 8 bytes of
 CoAP Etag would significantly reduce the collision probability.  (Still
 not "correct", but maybe tenable for certain applications.)

-- 
----------------------------------+-----------------------------------------
 Reporter:  cabo@…                |       Owner:        
     Type:  protocol enhancement  |      Status:  new   
 Priority:  minor                 |   Milestone:  ietf80
Component:  coap                  |     Version:        
 Severity:  Active WG Document    |    Keywords:        
----------------------------------+-----------------------------------------

Ticket URL: <http://trac.tools.ietf.org/wg/core/trac/ticket/123>
core <http://tools.ietf.org/core/>

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From: Zach Shelby <[email-masked]>
Date: Fri, 11 Mar 2011 11:00:41 +0200

> not "correct", but maybe tenable for certain applications.)

Good point, I am OK with this change, although we should recommend that short Etags should be used whenever possible. 

Zach 

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Zach Shelby, Chief Nerd, Sensinode Ltd.
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From: "core issue tracker" <[email-masked]>
Date: Sat, 12 Mar 2011 15:08:39 -0000

#123: Etag size

Changes (by hartke@…):

  * status:  new => closed
  * resolution:  => fixed

Comment:

 Fixed in [235]:

 Fix #123

-- 
----------------------------------+-----------------------------------------
 Reporter:  cabo@…                |        Owner:        
     Type:  protocol enhancement  |       Status:  closed
 Priority:  minor                 |    Milestone:  ietf80
Component:  coap                  |      Version:        
 Severity:  Active WG Document    |   Resolution:  fixed 
 Keywords:                        |  
----------------------------------+-----------------------------------------

Ticket URL: </ticket/123#comment:1>
core <http://tools.ietf.org/core/>