Hi,
Following my earlier posting, I've had qute a few people ask me about how
(and why) we use AOLServer in a mobile context. Apologies if this is not
entirely appropriate to the list but as so many people asked....
We develop services that are 'mobilized' which means that they can be used
from a range of interfaces, all essentially communicating with a single
server-side application.
WAP (or more correctly WML) is essentially a mobile-specific attempt at a
markup language not entirely dissimilar to HTML (although there is no direct
relation between the two). I'll refrain from offering my personal opinion on
WAP/WML, as I'm sure everyone whose had to work with it is already painfully
aware of it shortcomings ;-)
When a mobile phone issues a WAP based request, it essentially connects to a
WAP gateway, more often than not provided by the mobile operator. This
gateway acts as a more intelligent node, on behalf of the phone. On good
gateways this will handle things like session management, billing
interconnectivity, and most importantly from a web development perspective,
it maintains 'cookies' on behalf of the phone user.
The wap gateway then issues requests to whatever service the user has
requested. These services are essentially websites capable of understanding
WML.
We use AOLServer as our general web server software, but we also extended it
so that it can understand (and serve up) WML as well as HTML. This is
actually achieved by extending the mime type/headers that AOLServer is able
to recognise. This allows us to use a common architecture for delivering both
kinds of content, with all the performance benefits of AOLServer. Performance
is of course critical for mobile services due to the very low bandwidth
available.
It goes a little further than this for us. In order to simplify the
production of web content for many devices types we also have to employ
clever, dynamic content management to serve up the correct content
appropriate for the interface, whilst ensuring that concurrent access from
any other device is also handled. We therefore also use the excellent ACS and
OpenACS to provide a starting point for this. There's actually a good piece
on the ArsDigita site about WAP but I don't have the URL to hand
unfortunately.
We use AOLServer for a number of other mobile based problems as well. Briefly
this covers:
- We extend AOLServer to act as an agent for interconnecting business systems
(such as billing and mediation) by serving up XML content appropriate for
Machine-Machine connectivity.
- We have a specialised service for the management of SMS traffic. This means
we can use text Messages to notify subscribers, or even support very simple
session management based on Text Messages, i.e. users can submit commands,
queries and responses via SMS.
- Support for mediation and micro-billing, v.useful when your dealing with a
mobile operator ;-)
As an interesting aside, AOLServer is also very competent for serving up
content based on i-Mode / cHTML. This is most interesting as we're likely to
see the Japanese technology emerging in Europe later this year.
Apologies for the length, hope its of some use. Don't hesitate to mail us if
you wanted to know anything else (if its not appropriate for the list).
Cheers
Simon
www.open-msg.com
