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Re: Tokyu CATV (was Re: Metallic DSL in Tokyo)



On Mon, Oct 30, 2000 at 02:39:10PM +0900, Stephen N. Carter wrote:
> Didn't I see a note by Simon Cozens when this thread started that he 
> was compiling some sort of useful FAQ? 

Patches are welcome!


        Tokyo High Speed Internet FAQ
 
1.0 About this FAQ

2.0 ISDN

3.0 OCN

OCN is a service offered by NTT; it looks like ISDN, smells like ISDN,
and requires an ISDN terminal adapter, but it isn't ISDN. It's an
unmetered, statically allocated digital service, and comes in three
flavours: Economy is probably the one you want, but a misnomer at
32,000Y a month.

This'll give you a 128kbps line which is shared between the other OCN
subscribers at your local exchange. Naturally, your actual download
rates will vary depending on how many other subscribers are on your
exchange and their bandwidth usage. Personally, I had this service in
Jiyugaoka and managed to almost always get the full bandwidth, with
downloads averaging around 10 kilobytes/s.

The economy service will give you 16 IP addresses, so to use them you'll
either need a router or a clever Linux box. To connect to OCN with
Linux, just use pppd and have it go off hook with "ATDT0" or similar.

Now, with ADSL approaching, I'd say the only reasons for getting OCN is
that you can run services freely, and that it's available pretty much
everywhere.

4.0 ADSL

If you live in one of the following areas:

    Kayaba-Kabuto (Chuo-ku) 
    Aoyama (Minato-ku) 
    Mita (Minato-ku)
    Yotsuya (Shinjuku-ku) 
    Yodobashi (Shinjuku-ku) 
    Ikebukuro (Toshima-ku)

you're greatly in luck - it's likely there'll be an ADSL service available
to you. As the ASDL rollout continues, we can expect this list to grow.

As far as providers:

    4.1 NTT-ME

This is an ADSL service offered by NTT: it comes in two brands,
the "Personal" service and the "Professional".

The Personal service gives you one IP address at 6,890Y per
month. The Professional service is 26,400Y a month, but gives
you 13 IP addresses, your own domain, primary DNS and all the
trimmings.

Ayako Kato reports:

   The speed they advertise is 512Kbps downstream, 224Kbps upstream for this
   "personal" service I use. I usually get up to 40 - 50KB/s down at night,
   which is not bad at all. I was told it may be slower during daytime, but
   I'm never home during the day anyway. I have never felt anything was
   "slow" since I started using it.

   There isn't any filter that block incoming traffic to ports < 1024. I have
   a few ports open on the gateway box but have never had problems reaching
   them from outside. (Configuring them correctly is a different issue. A few
   very skilled people helped me set things up and gave me tons of advice.
   Thanks Chris. :) )

   I can see that a lot of my neighbours (IP-address wise) are running Linux
   and have various services enabled, ... http, ftp and even telnet(!!).
     
    4.2 Tokyo Metallic

Tokyo Metallic (http://www.metallic.co.jp/) offer a "Single 640" plan at
5,500Y. While the address is theoretically dynamically allocated, it
seems not to change and is probably static DHCP. It used to be translated
using NAT so you couldn't connect to it from outside, but now they are
using real-world IP addresses; however, the DSL gateway they supply appears
to block well-known ports, so running servers from this is not an option.
(unless you want to run them on weird ports...)

According to Johnathan Shore:

    BTW, their service is excellent - have found that it delivers the
    advertised bandwidth (unlike many installations in the US).  I
    regularly get ~70KB/s on the 640, though you'll find that there are
    many places on the wan that cannot even sustain that. 

Their "business plan" is an SDSL which allows you to run servers is
32,000Y a month. (More information about this would be appreciated!)

5.0 Cable Modem

    5.1 Tokyu Cable

They use some sort of IP masquerading so that hosts inside their
net can not be seeing from outside. UDP packets are blocked at
the gateway. IP addresses assigned by DHCP are in the private
address space. Their own Internet connection is provided by IIJ
through a 100Mbps link. Internally, they have a 622Mbps ATM
backbone connecting their 6 re-broadcasting stations. Bandwidth
from these stations to the cable modem is said to be 14.3Mbps
(the cable modem rental fee is included in the service, 5200 yen
per month, or 7000 yen/month for the Internet+CATV service --
CATV alone is 3800 yen/month). The cable modem brand is "Terayon"
http://www.terayon.com/products/cablemodem/modem.shtml
A hub can be connected to it, allowing more than one computer
to be on the net (they all get their IP addresses by DHCP).

[Thanks, Alberto!]

-- 
There seems no plan because it is all plan.
		-- C.S. Lewis


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