An Architecture for Wireless LAN/WAN Integration 2004-21582 IDS LAB 이상희

Contents Introduction The Full Stack Adaptation Project Integrating Mobile-IP with Multi-cell Wireless LANs Background on Mobile IP Mobile-IP based Wireless LAN Experimental Analysis The Testbed Handoff coercion and propagation Experimental Results Conclusion

Introduction Two new paradigms of recent advances Nomadic computing Using IEEE 802.11 Low mobility (up to 5M/h) High bit rate (2 to 25 Mbps) Mobile computing GSM, CDPD, iDen High mobility (up to 60 M/h) Low bit rate (9.6 Kbps to 40 Kbps)

Introduction What is needed for truly ubiquitous connectivity is “Adaptability Infrastructure” So bridging wireless WAN and wireless LAN will fuse in the economical advantages and the high bit rate of wireless LAN with ubiquity and ad-hoc mobility allowed by wireless WAN.

Introduction To realize this vision Full Stack Adaptation Integrating Mobile IP into the FSA architecture Superimpose Mobile IP on Wireless LANs Subnet Architecture Using the Mobile IP protocol

The FSA Project No single wireless network technology meets the ideal of high bandwidth, low latency, universal availability, and low cost Full Stack Adaptation the architecture that integrates horizontal and vertical handoff, while allowing applications to participate fully in the handoff process

The FSA Project The FSA architecture allows A two-way interplay between applications and network connectivity on vertical handoffs. Applications to provide recommendations to the handoff mechanism that can result in substantial savings.

The FSA Project Using Mobile-IP protocol To integrate vertical and horizontal handoff To provide a fixed IP solution under multiple networks Enable handoff across Cells in same / different network

The FSA Project Role of each layer Vertical LAN/WAN handoff Layer Monitor network characteristics Power… etc Application Adaptation Layer Decide vertical handoff Thin Client The use of thin clients as an alternative to specialized proxies

Integrating Mobile-IP with Multi-cell Wireless LANs Background on Mobile IP

Integrating Mobile-IP with Multi-cell Wireless LANs Mobile-IP based Wireless LAN Simplest solution is to impose a one-to-one mapping between wireless cells and sub-networks. It calls Subnet Architecture, SA It requires The detection of the MAC-level handoff occurrence on the mobile node Subsequently initiating a Mobile IP handoff between the two networks

Integrating Mobile-IP with Multi-cell Wireless LANs Mobile-IP based Wireless LAN Generalization of SA is a many-to-one mapping of cells to subnets Case of intra-subnet mobility Only MAC-level handoff Case of inter-subnet mobility MAC-level and Mobile IP level handoff It allows for higher flexibility in the design of the subnet based on administrative or work affinity instead of spatial affinity

Integrating Mobile-IP with Multi-cell Wireless LANs

Experimental Analysis Testbed Mobile Node can hear from both of APs

Experimental Analysis Handoff Coercion and Propagation In the one-to-one mapping SA, the handoff at the MAC layer means that the Mobile IP handoff should be performed immediately. Using handoff controller, we make the handoff by software.

Experimental Results To quantify the overhead of the composite MAC/Mobile-IP handoffs and to compare it with MAC-only handoff To determine the range of acceptable handoff frequencies, within which degradation of TCP performance is acceptable

Experimental Results IEEE 802.11 Handoff only

Experimental Results Composite IEEE 802.11 and Mobile IP Handoff By Mobile IP Handoff

Experimental Results TCP Performance Evaluation

Conclusion We present An architecture that aims at integrating wireless LANs and wireless WANs The role of the Mobile-IP as an integrative layer A simple subnet architecture that allows us to superimpose Mobile-IP on wireless LANs Under practical values of handoff frequencies, the performance of Mobile IP based W-LAN handoff is almost identical to the performance of W-LAN handoff