Fred;
For the record, I'm sitting at this instant in Tokyo Station, and am on my
way from Narita to Yokohama. I am sitting in the green car, and I accessed
the appropriate web page.
Note that that is an experimental service of JR, itojun mentioned,
and has nothing to do with MIS service, I mentioned, subject line
of which you copied.
Anyway,
I have wonderful 802.11 connectivity, and I have an IP address. Whether
that means I can use the Internet is another question. On the parts of the
track where the connectivity is there, we see ping round trip delays
varying from 380 ms to over four seconds. There are fairly large parts of
the track where the NTT DoCoMo 3G data connectivity appears to simply not
be there - especially when in concrete tubes and ditches, but also on
places with open track.
As you know, JR uses not IP mobility but telephone network mobility.
So, it is a problem of a plain old telephone system so called 3G. :-)
So I think here the term "seamless", when applied to connectivity, doesn't
really apply.
Direct WLAN service, today, has much less service area.
However, in the future, inexpensive base stations of WLAN are
essential to cover small holes of connectivity.
Masataka Ohta