(keitai-l) Re: traffic management

From: Ian Mansfield <ian.mansfield_at_amplefuture.com>
Date: 03/22/05
Message-ID: <QjE2VFhINiV7IE45QF01NjkzMDIxNjI1@ianm>
I cant speak for Japanese networks, but certainly within the GSM system there is a capability for offering priority to select handsets during times of high congestion on a cell due to a local emergency.

This was even available back in the ye olde days of analogue (or analog for some of you!) - for the ETACS platform - part of the programming involved a two digit code, and some of the available numbers were reserved for use by the police etc., and we would need a government order to permit us to add them to handsets when issuing them to customers.

However, even without that - on a GSM network the data carrier is often separated from the voice channels, so it is quite easy for a cell to be flooded with voice callers and still have capacity on the data side.

This also applies for SMS which is carried on a totally different part of the network.

A final factor is the bursty nature of the data call - which means in an area where voice is unreliable, you can often still make a data connection, albeit a slower one as corrupted data packets are regularly resent over the network.

I have often advised people in rural or congested areas who are desperate to contact someone to use SMS as the data connection is traditionally a lot easier to make than a circuit voice connection.





---------- Original Message ----------

FROM:      nick may <nick@kyushu.com>
TO:        keitai-l@appelsiini.net
DATE:      Tue, 22 Mar 2005 16:41:45 +0900

SUBJECT:   (keitai-l) traffic management

Does anyone know what traffic management is available on Japanese 
carrier networks in emergencies? Is it done just by "number called" or 
are some handsets more equal than others?

It was quite noticeable in the immediate aftermath of the main (6.6) 
tremor Sunday's earthquake down here in sunny F. (which isn't actually 
finished yet - we had a 4.8 aftershock a few minutes ago...) that one 
could connect to send email, but not to make a call - which suggests 
that it wasn't cell capacity that was the issue.

I have a suspicion that in-network calls were easier than cross network 
calls - but can't confirm. Is that likely?

Nick

(For those looking for something new to have an office sweepstake on, 
we are having much fun locally with the following page - 
http://www.hinet.bosai.go.jp/ (Japanese - but with big map). It records 
tremor data within about 45 seconds of the tremor ending - impressive, 
even by Japanese standards. We wait for the walls to stop shaking, bet 
on the magnitude, then hit the net to check. Astonishing how many 
tremors Japan has each day. Of course, you could just bet on location 
and magnitude, no need to be in-situ...)


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Received on Tue Mar 22 11:15:47 2005