Wireless Base Station Development
The TKN Group tests, measures and develops link and network layer protocols
and extensions designed to raise wireless network performance.
For our experimental wireless LAN setup environments, the mobile host is
generally some PC-type notebook computer, where we are able to implement
protocol changes in the link or network layer through the use of open
source
operating systems such as Linux. The commercially available wireless base
stations, however, have designated hardware and a proprietory programming
interface. In order to be able to implement such wireless base station
protocol extensions, we had to build our own base station.
Base Station Features
The base station is implemented on an ordinary PC running Linux. It is a
generic link level transparent bridge module with special extensions for
wireless devices. It can be used both as a testbed for link layer
extensions,
and also as a low cost wireless base station, running in the background of
any
PC workstation, needing only a wireless adapter card.
In short terms:
- generic link level base station (bridge)
- uses 802 type addressing (link layer transparent)
- to be used with any 802 network device (including 802.11)
- uses linux wireless extensions to identify wireless devices (and thus
staying device driver independant)
- packets can be passed through arbitrary protocol handlers
Different protocols have already been implemented: the Snoop protocol
and a new approach called remote
socket architecture.
Figure 1:
Schemativ overview of wireless base station and Snoop agent