Re: quick failover in SCTP

[Michael Tüxen <[e-mail]>]

On Oct 14, 2010, at 4:14 PM, David Lehmann wrote:

>>>>> I would like to see some extensions to you suggestion:
>>>>> * Introduce a threshold (call it PFMR for now).
>>>>>  Then use
>>>>>  if (error counter > PMR)
>>>>>     the path is inactive.
>>>>>  if (error counter <= PMR) && (error counter > PFMR)
>>>>>     the path is potentially failed.
>>>>>  Using PFMR = 0 is what you suggest, PFMR=PMR gives
>>>>>  the old behavior.
>>>> 
>>>> I thought similar thing and I agree with providing a way to disable PF.
>>>> I tend to agree with this idea, but one thing I'm not very sure is how
>>>> PFMR != 0 && PFMR < PMR can be useful.
>>> I could image someone wanting to call a path potentially failed
>>> after 2 consecutive timer based retransmission instead of 1.
>>> Just being a bit more conservative. This might help deploying
>>> such a feature in SIGTRAN networks where CMT is not deployed.
>>> For CMT traffic, PFMR==0 is the right choice, I guess.
>>> But I think PF is also very helpful in non-CMT scenarios.
>> 
>> OK. I think it would be good to have tunable parameter for users. I
>> agree with this.
> 
> Just to be clear the default would be PFMR == 0, which means use another path if the error count is non-zero.  Correct?
Correct.

Best regards
Michael
> 
> -David
> 
>