Re: tlug: cable modems

[Jonathan Byrne <j-byrne@example.com>]

shimpei@example.com (shimpei@example.com) wrote:

> Well, their top page claims that they just upgraded their uplink to 70Mbps
> (from 55Mbps). Assuming that the uplink from there has decent pipe to the
> world, it wouldn't be quite that pathetic. OTOH, Even 70Mbps doesn't sound
> all that big in this day and age.

Whether or not 70 mbps is big or not really depends on what you're trying
to push through it.  As long as the bandwidth isn't oversold, it
should be fine.

Where that 70 mbps goes is, of course, also important.  If it goes
straight to a NAP (JPIX or NSPIXP2), their connections with peers 
there would be pretty good.  If it only goes to a provider that
is at a NAP, that's another hop away.  If it goes to a provider
that isn't directly connected to a NAP, add at least one more hop.

And if that is just one pipe, beware the Day of the Backhoe.  Fibercuts
seem fairly uncommon in Japan, but they are practically a recreational
activity for backhoe operators in North America.

It's also possible that their 70 meg is their total aggregated 
bandwidth.  The fact that no network map or other detailed
info appears anywhere on the site (at least not that I could find)
makes we wonder about their network architecture, or what they might
be hiding.

Also, interestingly, this page seems to say that they have a 70 meg
uplink but the interal bandwidth of the network is 14.3 mbps, on a
total ATM backbone of 622 meg.

http://www.catv.ne.jp/internet/

Am I reading that correctly?



> The cable company with the really pathetic uplink is the company serving my
> area, Ota Cable Network, which proudly proclaims an uplink of 6Mbps. Sigh...

Well, as long as they only have a few dozen users that might be OK :-)

Jonathan

-- 
Jonathan Byrne <j-byrne@example.com>               Engineering Division
Exodus Communications K.K./Global Online Japan      http://www.gol.com/
Tel:  +81 3-5334-1700   Fax: +81 3-5334-1702        Direct: +81 3-5334-1756

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