developerWorks: Build a WAP Gateway On Linux
Jun 13, 2004, 19:30 (1 Talkback[s])
(Other stories by Manas Ranjan Behera)
The WAP gateway works by letting a telephone act as a simple Web
browser with optimized markup language, scripting language, and the
transmission protocols for wireless-over-the-air use. It talks to
the phone using the WAP protocol stack and translates the requests
it receives to normal HTTP. Therefore, content providers can use
any HTTP server and utilize existing know-how about HTTP service
implementation and administration.
"In addition to protocol translations, the gateway also
compresses the WML (Wireless Markup Language) pages into a more
compact form, which saves bandwidth on the air and further reduces
the phone's processing requirements. It also compiles WMLScript
programs into a bytecode format.
"There are various commercial WAP gateways available on the
market that are quite expensive. Kannel, on the other hand, is an
open source gateway; you don't need to pay for it, you can edit the
source code yourself, and you can construct your own customized
gateway. Because Kannel is being developed on Linux systems (RedHat
and Debian), it can be smoothly ported to other UNIX-like operating
systems. However, in this article, I illustrate building the
gateway for these two Linux systems only..."