[Bloat] If you were me, and talking at NANOG....

[BeckW at telekom.de]

> I have yet another talk to give next week at NANOG. http://www.nanog.org/
>
> Some of you on this list have lots more experience running networks than
> I do, and are at least noddingly familiar with bufferbloat, or would not
> have subscribed.
>
> What points would you make to a group like NANOG?  Send to me privately
> unless you think your insights are of general interest.

some random points:
- Some regulatory bodies require that an operator can only charge for packets that are really delivered to the customer. If you sell volume-based plans, you better queue packets, even if that means non-optimal service for your customer..
- ISPs often sell/provide home routers; the buffering behaviour varies a lot. Specifying -- and testing -- proper buffering is necessary.
- slow upstream links cause a lot of inherent delay that looks like bufferbloat (well, the slow link *is* a buffer); some home routers fragment packets into small chunks so that real-time flows don't get delayed too much. This does not work with IPv6 as the minimum fragment size is pretty large. Manipulating TCP headers (MSS, receive window) might help.

Regards,

Wolfgang Beck