(keitai-l) Re: AW: Re: SMS/mobile Internet/TV

From: Ken Chang <kench_at_hotmail.com>
Date: 10/16/02
Message-ID: <F134SQeSOzNCWbzwWJv000002eb@hotmail.com>
I'm sorry to drive the thread off marketing and to the mail system,

one point I wanted to make was that if you choose to use a proprietary
system, i-mode, and new handsets, you can have tagged messages to include
color, format, emoji, etc., as an extension or parallel to the ITS on top
of SMS.

i-mode took off with two engines: text messaging and ring-tone download.
you can do both with SMS (not the new 32/40 polyphonic melodies though).

about the speed of wireless messaging, the i-mode mail is quite fast,
about 3 sec from submission to delivery finishes (handset rings, would
please someone give us test results around clock to PDC/FOMA handsets?),
if network can reach the handset (70% of time as we discussed before).

but this is possible because,
(a) only short text messages of up to 500 bytes (no attachment)
(b) one shot delivery as opposed to notification-retrieve used by ezweb
(c) J-Phone uses 3 concatenated short messages and takes twice the time

there two kinds of delayed delivery
(1) the first is many students chat with classmates in classroom using
mobile phones.  they found that after you press the send button, the one
with a DoCoMo handset will feel the vibration almost immediately while
an au/KDDI guy will get it after some 20 sec or more, because the au
network sends an SMS (Cmail) first and then the handset calls back to
start an IMAP4 session.

the classroom case is not considered in any mail system design (incl.
IM), because a mail system is not real-time and 3 or 30 sec are normally
considered same as no delay.  if you configure to choose Cmail, to
trade-off large message with attachments, the handset will ring within
3-5 sec.

(2) the second is retry.  a busy system may delay messages for several
minutes, but I think if you get a message delayed for long time, the most
likely reason is your signal was not reliable, or the base station was
too busy, in the first 30 min or so that the server failed first several
retries.  this happens more frequently with J-Phone's PDC network than
au's cdma2000 network.

DoCoMo has poorer radio because it has smaller cells interfering with
each other.  it should have worse mail delay problem if it had had retry.

in conclusion, the au's problem is slow message retrieval, resulting a
delay of about 20 sec.  the J-Phone's problem is PDC network capacity,
and delays for ten minutes or so.  if your messages get delayed for
hours many times in a month, then the problem may be that J-Phone axed
their capex too much to accommodate increased traffic.

cheers,

Ken

_________________________________________________________________
Get a speedy connection with MSN Broadband.  Join now! 
http://resourcecenter.msn.com/access/plans/freeactivation.asp
Received on Wed Oct 16 18:15:45 2002