Re: [Stox] Comments on draft-ietf-stox-im-11

[Ben Campbell <[e-mail]>]

On Feb 13, 2015, at 9:21 AM, Peter Saint-Andre - &yet <[e-mail]> wrote:

>> Proposed text for a new section in stox-chat...
>> 
>> ###
>> 
>> 8.  Message Size
>> 
>>    Unlike page-mode messaging [RFC3428] (which specifies that the size
>>    of a MESSAGE request is not allowed to exceed 1300 bytes), session-
>>    mode messaging [RFC4975] can be used to send larger messages.  MSRP
>>    includes a chunking mechanism such that larger messages can be broken
>>    up into multiple MSRP SEND requests.  Because the MSRP gateway at an
>>    XMPP service acts as an MSRP endpoint, it is responsible for
>>    receiving chunked messages and reconstructing them into a single
>>    message for delivery toward the XMPP recipient.  (Naturally,
>>    implementations need to be careful about accepting very large
>>    messages; see Section 14.5 of [RFC4975].)
>> 
>>    Although there is no hard limit on the size of an XMPP stanza, in
>>    practice most XMPP services (at least on the public Internet) are
>>    configured with a maximum stanza size in order to help prevent denial
>>    of service attacks.  As specified in Section 13.12 of [RFC6120], this
>>    maximum is not allowed to be less than 10,000 bytes.
>> 
>>    The administrators of an XMPP service need to ensure the associated
>>    MSRP gateway is configured with the same or smaller maximum MSRP
>>    message size as the maximum XMPP stanza size; this enables the
>>    gateway to return an appropriate value for the SDP "max-size"
>>    attribute and to properly handle messages larger than the configured
>>    limits.
>> 
>>    If an MSRP-to-XMPP gateway implementation receives an MSRP message
>>    that exceeds its configured limit as just described, it MUST return
>>    an MSRP 413 error (e.g., in response to the first SEND request whose
>>    Byte-Range header field indicates a byte total exceeding the limit).
>> 
>> ###
> 
> Ben, let me know if that text looks OK. It seems that we'll want to add a pointer from the -groupchat document to this section, too, eh?

Yes, and probably. 

> 
> I think this is the last open issue from your reviews, so once you say it's OK I'll submit revised I-Ds for -im, -chat, and -groupchat.

Agreed.