Abstract
This thesis comprises two topics for the integrated 3GPP and WLAN networks. First, IP Header Compression protocol (IPHC) is implemented to reduce packet loss rate over lossy links. Second, the proposed pre-authentication could reduce the handoff delay in integrated 3GPP/WLAN networks. 3GPP has already proposed an architecture for the interworking of 3GPP and WLAN systems. However, the 3GPP solution leads to one issue: each time when handoff happens, there is a long delay incurred by authentication before one can access to WLAN or 3GPP system. This is unfavorable for the integration of 3GPP and WLAN systems. Based on 3GPP architecture, this thesis presents a pre-authentication technique in which the authentication procedure could be executed before handoff.