Re: [hybi] hum #3: Message

[Douglas Otis <[e-mail]>]

On 8/6/10 1:19 PM, Dave Cridland wrote:
> On Fri Aug  6 15:17:19 2010, John Tamplin wrote:
>> Ok, does this summarize the various positions regarding chunking and
>> lengths?
>>
>>
>>    - We want to have a length of the complete message when it is 
>> available
>>    to make buffer management simpler for the receiver
>>    - We want to be able to fragment messages to avoid extra buffering 
>> when
>>    the length of the entire message is not known up front, such as 
>> when sending
>>    dynamic content, compressing frames, etc.
>>    - We want to keep small frames having small overhead (though there 
>> is a
>>    limit on how much this matters given TCP/IP overhead)
>>    - We want to be able to send very large files in a single fragment 
>> so we
>>    can just hand it off to sendfile or equivalent
>>
>> What about the following:
>>
>>    - 1 bit - Initial fragment
>>    - 1 bit - Final fragment
>>    - 1 bit - reserved
>>    - 5 bits - opcode
>>    - 8 bits - short length
>>    - [if length = 255: 8 bytes - length]
>>    - [if Initial = 1 and Final = 0: 8 bytes - overall message length, 
>> with 0
>>    meaning "unknown"]
>>    - length bytes of payload
>
> I'm fine with this.
>
> It feels like a solid starting point.
+1

-Doug