[e2e] end2end-interest Digest, Vol 25, Issue 26

[Fred Baker]

If you're interested in maintaining connections, then why would you  
not use SCTP? SCTP allows you to maintain an overall connection and  
then do fast transaction-like sessions at will within the context.

http://www.ietf.org/rfc/rfc2960.txt
2960 Stream Control Transmission Protocol. R. Stewart, Q. Xie, K.
      Morneault, C. Sharp, H. Schwarzbauer, T. Taylor, I. Rytina, M.  
Kalla,
      L. Zhang, V. Paxson. October 2000. (Format: TXT=297757 bytes)
      (Updated by RFC3309) (Status: PROPOSED STANDARD)

http://www.ietf.org/rfc/rfc3257.txt
3257 Stream Control Transmission Protocol Applicability Statement. L.
      Coene. April 2002. (Format: TXT=24198 bytes) (Status:  
INFORMATIONAL)

http://www.ietf.org/rfc/rfc3286.txt
3286 An Introduction to the Stream Control Transmission Protocol
      (SCTP). L. Ong, J. Yoakum. May 2002. (Format: TXT=22644 bytes)
      (Status: INFORMATIONAL)


On Mar 26, 2006, at 9:57 PM, Michael Welzl wrote:

>>> To me, there's just one open question. When all nodes authenticate
>>> themselves in a Grid, why don't they just set up and maintain TCP
>>> connections to each other forever?
>>
>> Because processes come and go, I'd think.  Plus, perhaps, a dose
>> of "basic TCP can work to anywhere; it saves on management costs
>> to use it everywhere".
>>
>> On the other side of the coin, in such a trusted environment, I
>> don't see why you shouldn't send
>>
>>   1) -> SYN, query data, FIN
>>   2) <- SYN, response data, FIN, ACK(SYN+query+FIN)
>>   3) -> ACK(SYN+response+FIN)
>>
>> without going the whole hog on T/TCP.
>
> Hm, isn't doing this type of communication what T/TCP is
> all about?
>
> With normal TCP, the host which is contacted in 1) would
> be allowed to receive the "query data" and buffer it
> somewhere, but not deliver it to the application before
> the handshake is over according to RFC 793. While this
> offers some protection against DoS attacks, I think we
> could drop this requirement in a trusted environment.
>
> The question is really whether this is a big issue for
> anything except my Grid scenario  :-)   , and if this
> particular scenario couldn't also be handled by
> maintaining connections instead of changing TCP...
>
> Cheers,
> Michael