Re: [tlug] Network issues Japan -> USA?

[Curt Sampson <cjs@example.com>]

On 2008-12-10 14:25 +0900 (Wed), Ian Barwick wrote:

> The network people at the US hoster say the problem is with the ISP's
> upstream provider...
> I've tried contacting our ISP (AsahiNet) in the hope they will pass
> the message on to someone who knows about these things (rather than
> asking me to reboot my PC).
> 
> Does anyone have any experience in contacting  Asia Netcom directly
> (or getting the ISP to deal with this kind of issue)?

The issue here, and one of the reasons that I've not replied to this
(besides that I've not been involved in inter-AS routing for a decade or
so now) is that these sorts of problems are tricky, and debugging them
is a problem of great subtlety.

Your best bet is to put together the simplest way you can find to
reproduce the problem, perhaps along the lines of a couple of wget
commands. One would be to a site reached though the problematic upstream
provider, and the other not, and the first would demonstrate the problem
and the second wouldn't. Then you can ask an AsahiNet tech. to try to
reproduce it from one of his machines.

(Incidently, AsahiNet does have some good techs. in there somewhere, and
they are reachable through front-line support if you can provide the
right information. They helped me debug an annoying PPPoE authentication
problem a year or so ago without any serious difficulties or delays.
However, "the right information" often turns out to be things like a
pcap packet dump file along with an annotated dump of that showing where
things appear to be going wrong.)

Going up to the upstream provider is very unlikely to help, in my
opinion, especially given that they're not in as good a position to
debug the issue as the guys downstream from them. I'm also suprised you
got a reply at all.

So sorry about this, but I guess the only useful advice I can provide is,
buy and study a copy of Richard Stevens _TCP/IP Illustrated_[1] Volume 1.
It's not a quick way to get to a solution, however.

[1] Oh, the full text is on-line! http://www.uic.rsu.ru/doc/inet/tcp_stevens/

cjs
-- 
Curt Sampson       <cjs@example.com>        +81 90 7737 2974
           Functional programming in all senses of the word:
                   http://www.starling-software.com