Mohsen writes:
Brijesh> PS: By the way, ReFLEX is perfectly fine for two
way messaging
Brijesh> applications.
No.
ReFLEX is not perfectly fine.
It is not IP based.
Hi Mohsen,
What kind of argument is this?
If it is not IP based it is not good ! This is an emotional response,
not a technical one. Using the same arguments, the whole phone system
isn't good because it has nothing to do with IP (or at least was true
till VoIP came), and same is true of all G2 TDMA, CDMA and GSM
cellular systems (and don't forget AMPS, CDECT and many other wireless
standards).
If you want to say that WAP is not good because it closes alternative
solutions, I very much agree with you (which a good reason to fight
for). But to say that an existing wireless standard that has millions
of users is no good, isn't a proper argument. I agree that ReFLEX is a
proprietary standard, and proprietary standards (with controlled
licensing as ReFLEX is) are bad for consumers - you can definitely
argue on that basis.
But you cannot argue on technical merits of the protocol itself
because it is very efficient in delivery of email messages. Using a 25
KHz channel it can support thousands of devices. It is not only very
efficient in usage of radio spectrum, and it is well known that
under-ground or in-building penetration of FLEX/ReFLEX systems is far
better than any other cellular systems. Of course, it is not designed
for interactive real time operations - but email doesn't require
sub-milli seconds response nor do many telemetry systems such as coke
machine and electric meters in houses. Even ARDIS network, the grand
daddy of wireless data networking in US, has nothing to do with IP.
The WAP's goal was to support just about every possible Radio layer.
It is all inclusive and does support IP devices (which use CDPD, GPRS
or CDMA/GSM - IWUs).
Moreover, TCP/IP isn't designed for wireless channels which have
limitations on bandwidth, frequent handovers, channel errors, and
periods when channel isn't available at all (of course, number of
solutions some of them are pure software hacks, such as snooping TCP
halfway at BS etc., have been proposed. Of course, we haven't yet
figured out how to initiate an application between two devices when
both sit behind NATs at this scale (try sending a TCP connection
message from one cellular phone to another cellular phone in the car
and assume that both have them have no permanent IP addresses !). You
will need true IPv6 without which IP with NAT isn't going to go long
distance in wireless devices.
What I wished to point out was that you definitely have a good
objective, but the approach is not right. The real issue is should all
technology be supported by a single set of WAP Forum derived
specifications. What is good for ReFLEX (@9600 bauds) isn't good for
CDPD at 19.2 Kbps and definitely isn't good at 170kbps GPRS, or 2
Mbits/sec G3 micro cells. I think there you have some good arguments.
Given that most cellular devices or systems come from three super
heavy weights, and two heavy weights, any solutions that doesn't get
supported by some of them, has little chance to get adopted in near
future. But try - you definitely can, and should.
Cheers,
--brijesh
Ennovate Networks Inc.
(my personal views only, and in no way reflect opinions of my
organization.)