[core] draft-ietf-core-observe-05 - "obs"

[Klaus Hartke <[e-mail]>]

In the spirit of "In protocol design, perfection has been reached not
when there is nothing left to add, but when there is nothing left to
take away" [1]:

Do we really need the "obs" link attribute?

Some thoughts:

* If a client wants to have a fresh representation of a resource over
a period of time, it can include the Observe option in its request. If
the server does not support -observe, the client can poll the resource
to achieve its goal.

* If a client for whatever reason only wants to have a fresh
representation of a resource over a period of time if the server
supports -observe, it can include Observe option in its request and
not poll if the if the server does not support -observe.

* If a client wants a single snapshot representation of a resource, it
can omit the Observe option from its request.

Under what circumstances can a client not be sure if it wants to have
a fresh representation of a resource over a period of time, so a hint
from the server is needed?


Klaus


[1] http://tools.ietf.org/html/rfc1925