Wednesday, February 25, 2009

UCT's extra bandwidth redux

[from a comment on the last post:]
Of course, SANREN is what's supposed to provide the drastically improved last-mile.
SANReN will eventually provide the core of the new network, and maybe the access leg too. Some Gauteng institutions have access via the fibre ring there and are happy. Many large institutions elsewhere don't have that yet (and are waiting, waiting, waiting) and are unhappy.

However, if the UCT link was increased from ~32 to ~44 Mbps (coincidentally this is like going from an E3 to a DS-3), what's to prevent it from being increased further? Why not a DS-4 (~274 Mbps) :)
BTW, the Google caches are already live. [We don't know for sure that these are GGCs, but see below ] Their effectiveness seems to be improving (presumably their caches are still filling), but they do still use quite a lot of incoming (international) bandwidth.
If these are Google caches (GGCs), I doubt they will have reduced international bandwidth usage much. The local usage would spike because access is so much quicker and easier.
Traceroute (ICMP, rather than UDP) to v1.cache.googlevideo.com
mt.google.com is also mapping to a TENET IP block, so Google Maps tiles should be served from somewhere local [TENET or GGC or who-knows-what].

kh.google.com [Google Earth] is still mapping to the Google IP addresses overseas.

mail.google.com and docs.google.com still map to the Google IP blocks overseas.

So either TENET has some sort of fancy caching and line-rate traffic redirection going on, or Google is doing something interesting.

Hopefully the local build-out will be finished soon.

1 comment:

Anonymous said...

SANReN will be providing access for a large number of institutions (though probably not all). See the first question in their FAQ and the Network Design Diagram later in the FAQ, too.

Re: E3/DS3/DS4. I doubt that technologies like that are playing any part in UCT's GEN3 connection.

Re: why not 274 Mbps? The simplest explanation is that UCT have just ordered more GEN3 bandwidth. GEN3 bandwidth is charged by the Mbps, so money (rather than the technology that's in use) limits how much bandwidth you can get.

Re: Google's buildout. Google have been promising local services for ages, but to date, South Africa's got nothing to show for all that talk except for a couple of caches on TENET. I guess I'm more cynical about what Google promises than you are.... :-|