[clue-tech] DSL providers

[Ken MacFerrin]

Mike Staver wrote:
> 
>> The basic benefit to interleaving is that it protects against
>> transmission errors and provides a more reliable connection by breaking
>> up and "mixing" several packets together before transmitting so that if
>> one packet gets corrupted, the remaining packets will still contain
>> enough information to recreate the corrupted packet without needing to
>> have data resent.  Unfortunately the mixing/de-mixing process nearly
>> doubles the latency of each packet.  If you have a poor physical
>> connection that's prone to errors then interleaving will be a good thing
>> as it will save packets from having to be constantly retransmitted.  If
>> your physical connection is good though, then it's just adding useless
>> latency.  I'm assuming the reason Qwest turns this on by default is
>> simple economics; most folks don't have a clue or care about latency so
>> it's not worth their time to do line testing.  In my case, turning off
>> interleaving dropped my average ping time from 70-80ms down to 35-45ms.
>>
> 
> Wow, that seems like a great incentive to turn it off if your connection
> is solid. I'll go ahead and call Qwest today and try having it turned
> off for my line since I think I have a pretty solid connection.  I guess
> if it doesn't help much with latency, then I'll have them turn it back
> on. I have a Cisco 678 - would that have to be rebooted after Qwest
> makes the change?
> 

I run an Actiontec modem in transparent bridge mode and didn't need a
reboot.  In fact, Qwest never even let me know they had removed
interleaving.  I just checked about a week after I put in the request
and my latency had dropped.  I called a tech and he confirmed it had
been removed the day before.
-Ken