Re: [sip-overload] Local Policy Re: I-D Action: draft-ietf-soc-load-control-event-package-05.txt

["Vijay K. Gurbani" <[e-mail]>]

I think the text Volker proposed below works, although it appears that
the explanatory sentence Volker added is applicable to only the first
paragraph.  I think that the sentence is equally applicable to all the
three SHOULDs.

I would, thus, suggest a small modification as detailed below.

On 01/14/2013 08:21 AM, Volker Hilt wrote:
> A SIP client SHOULD honor the local policy for prioritizing SIP requests
> such as policies based on message type, e.g., INVITEs vs. requests
> associated with existing sessions. A SIP client is expected generally to
> honor local policy except for very rare occasions when, for example,
> overload is so severe that messages, which should be preserved according
> to local policy, need to be discarded or local policies are in conflict.
>
> A SIP client SHOULD honor the local policy for prioritizing SIP requests
> based on the content of the Resource-Priority header (RPH, RFC4412
> [RFC4412]).  Specific (namespace.value) RPH contents may indicate high
> priority requests that should be preserved as much as possible during
> overload.  The RPH contents can also indicate a low-priority request
> that is eligible to be dropped during times of overload.
>
> A SIP client SHOULD honor the local policy for prioritizing SIP requests
> relating to emergency calls, as identified by the SOS URN [RFC5031]
> indicating an emergency request.

I would re-word as:

    A SIP client is generally expected to honor local policy for
    prioritizing SIP requests except for very rare occasions, when,
    for example, overload is so severe that messages that would
    otherwise be preserved according to local policy need to be
    now discarded.  Another example where local policies may not be
    honored is if these are in conflict.  Accordingly, the normative
    statements in the next three paragraphs should be interpreted in
    the context provided here and with the understanding that the SIP
    client will aim to preserve local policy to the fullest extent
    possible.

    A SIP client SHOULD honor the local policy for prioritizing SIP
    requests such as policies based on message type, e.g., INVITEs vs.
    requests associated with existing sessions.

    A SIP client SHOULD honor the local policy for prioritizing SIP
    requests based on the content of the Resource-Priority header (RPH,
    RFC4412 [RFC4412]).  Specific (namespace.value) RPH contents may
    indicate high priority requests that should be preserved as much as
    possible during overload.  The RPH contents can also indicate a
    low-priority request that is eligible to be dropped during times of
    overload.

    A SIP client SHOULD honor the local policy for prioritizing SIP
    requests relating to emergency calls, as identified by the SOS URN
    [RFC5031] indicating an emergency request.

Unless someone has objections, I will put this into the
soc-overload-control draft, and I suspect that Charles will do the same
for his draft.

Thanks,

- vijay
-- 
Vijay K. Gurbani, Bell Laboratories, Alcatel-Lucent
1960 Lucent Lane, Rm. 9C-533, Naperville, Illinois 60563 (USA)
Email: vkg@{bell-labs.com,acm.org} / [e-mail]
Web:   http://ect.bell-labs.com/who/vkg/