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Re: Tokyo high-speed access

Just a very rough description.  Somebody please fill in the blanks.

On Tue, 17 Apr 2001 13:35:43 +0100
Simon Cozens <> wrote:
> Tokyo High Speed Internet FAQ
> 2.0 ISDN
>     [You write this!]

2.1 INS64 & INS64-Lite

INS64 is NTT's name for their 2B+D ISDN service.  You can use each
B-channel as you would an analog phone line; basically, using it to dial
up to your ISP at up to 64kbps.  If your ISP supports it (most provide it
as an no-cost or extra-cost option), you can also use both B-channels to
dial up at speed up to 128kbps.  The connection is digital and symmetric;
there is little need to worry about line noise degrading the speed of your
connection like when using an analog modem.  (The reason I say 'up to
64kbps' is that there are different protocols you can use.  Most will use
the 64kbps one and almost all ISPs supports it.)

Other advantage of ISDN over an analog line is the line set-up time;
rather than waiting for modems to negotiate, which can take up to a minute,
ISDN line set-up takes only 1 or 2 seconds.

INS64-Lite is the same as INS64; the difference is political, and lies in
whether you want to purchase the <insert official name for 'Kanyu-Ken'
here>.  Kanyu-Ken is madatory for analog phone lines; without it NTT will
not provide you service.  You also need it for INS64 service.  However,
INS64-Lite service does not require it, at the expense of higher monthly

<insert section about cost here>

To use INS64 service, you will need to provide some equipments yourself,
namely (1) a DSU, and (2) an ISDN terminal adapter (TA) or an ISDN router.
A TA is usually connected to your computer via RS-232 or USB and looks
like a modem to it.  An ISDN router connects to your computer via ethernet,
routing traffic on your local LAN to your ISP.  Most modern ISDN routers
include functions such as NAT letting you share the same connection with
several computers on your private LAN, DHCP providing easy setup,
dial-on-demand, and etc.  TAs costs roughly 20,000Y to 30,000Y and routers
a little bit more.

2.2 Flet's ISDN

ISDN service, like analog phone service, is metered and local calls are
not free.  For the 'I must have internet 24 hours a day' crowd NTT
provides an option to INS64/INS64-Lite called Flet's ISDN.  For a monthly
fee of X,xxxY NTT gives you a special dial-up number which you can call
for free.  The number let you access a high-speed data network through
which you can access your ISP.  In practice, this just means you'll need a
TA or router that supports this service (most older ones have firmware
updates for it) and there is not much difference in setting up for this
service from normal dial-up.

You will also need an ISP that supports this service.  Most do but as an
extra-cost option.  IP address assignment is done by the ISP; most are
dynamic but some ISPs give you static IP if you pay for it.

This service is limited to 1 B-channel (64kbps) only.

> 3.0 OCN

> 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.

ADSL is now available to most of the 23-ward, and can be expected to
spread to close-by areas like Kawasaki.

As far as I know, all ADSL vendors rent their line from NTT; some provide
their own equipment and some uses NTT's.  No matter which vendor you
choose, there are two options: with or without analog phone service.  ADSL
is a data-only service.  If you want telephone service on the same line as
well, you will need Kanyu-ken (78,000Y from NTT, less from stores) and pay
the basic monthly fee for analog phone service.  As of now NTT does not
offer ADSL with ISDN on the same line.  If you just want a data-line, you
will not need Kanyu-ken, but the monthly service charge is higher and
comes out to be about 100Y less than ADSL+analog phone per month (i.e. you
basically only saves the Kanyu-ken money and sacrifice phone service).

>     4.1 NTT-ME
>     4.2 Tokyo Metallic

4.3 e-Access

4.4 Flet's ADSL

Flet's ADSL is NTT's own ADSL service.  It reuses the infrastructure for
Flet's ISDN.  You are connected to NTT's high-speed network which in turn
connects to your ISP.  Speed is up to 1.5Mbps downstream and 512kbps
upstream, depending on line quality.  IP address is assigned by the ISP
and most give you 1 dynamical IP.

Although the line is flat-rate and usable 24 hours a day, a connection
needs to be set-up when you use the line, like dial-up.

Advantage over other ADSL services is that you can provide your own ADSL
modem or rent it from NTT; if you choose to rent (about 500Y/month), then
the set-up fee would be only a few thousand yen, compared to the >30,000Y
sign-up for Metallic & e-Access (and I don't think you get to own the
modem even if you pay that.)

>     4.3 NTT's SDSL Plan

AFAIK not yet offered, still planning?

4.5 ...

There are other ADSL providers, but I don't remember them off-hand.

> 5.0 Cable Modem
>     5.1 Tokyu Cable

6.0 Fiber to the home (FTTH)

6.1 NTT's FTTH

6.2 Yusen's FTTH

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