After the good experiences we had made with offline editing of patient data and with mobile QA data acquisition, the next logical step was to build up a wireless network (WLAN). In 2004, we entered the wireless world by installing four WLAN access points (Cisco Aironet 1200), two on each floor.
Using WLAN in radiotherapy departments is a challenge, since treatment rooms are usually well shielded. To get equal coverage in all rooms, several access points are necessary.
The
WEP encrypted hospital network, using Protected EAP. |
WLAN connection quality was tested by performing an Eclipse dose calculation in different rooms. With the four access points, this is no problem in most areas of the institute (roaming is also supported). In the linac treatment rooms, signal strength is poor due to shielding:
The
Error message "DBPROCESS is dead or not enabled" indicates that
Eclipse lost connection to the calculation server. |
Only near the maze, dose calculations are possible:
Due
to poor connection quality, it takes quite a long time until the patient
is loaded. |
Finally,
the dose calculation shows progress. |
This simply means that treatment rooms require additional access points if WLAN is needed there.
In
areas with high signal strength, speed is 54 Mbps. |
Inside
the treatment room, speed is reduced to 18 Mbps. |
After nearly one year of usage, WLAN proved to be a useful and reliable networking extension. The Cisco components can be highly recommended in the hospital environment. And last but not least: wiring laptops is simply not sexy.