The usage of W-LAN increases rapidly today, and may be seen as a
threat to GPRS and 3G. However a combination af all technologies seems
to be a good solution, and is sometimes referred to as 4G.
This thesis investigates the mobility management in 4G. This includes
moblility within a W-LAN hotspot based on IEEE 802.11b, mobility between
hotspot-subnets, mobility between different hotspots and mobility
between different network technologies such as W-LAN, GPRS and UMTS.
The protocols Dynamics HUT Mobile IP, Cellular IP and Mobile IP are
proposed to solve the mobility management and this thesis investigates
and compares them from different aspects. Both Dynamics HUT Mobile
IP and Cellular IP show a much better performance than Mobile IP,
but the performance between them is similar.
An alternative solution called Columbitech Wireless VPN based on
session mobility is investigated and compared to Mobile IP based solutions.
Columbitech Wireless VPN seems to adapt to different networks in a
more convenient way compared to Mobile IP based solutions.