Following is the summary of Group 4 discussion on: Performance of Wireless
Networks

1. Problems in wireless network performance
    - Most start by solving lower layer issues (e.g., PHY/MAC delay, bit
rate, propagation time enhancements)
2. What really needed is layer-by-layer optimizations
    - Each layer is improved in an isolated manner
3. Must also perform cross-layer work, which coordinates and realizes the
layer-by-layer optimizations
    - E.g., Use of bit error rate for wireless TCP, link layer triggers to
synchronize fast IP handovers
4. Most of all, understanding on mobility will bring good results
    - In relation to applications/services
5. Side issues discussed
    - Hardware for experiments: programmability and modularity very
significant
    - Need of new performance metrics: not only object measures but also
subjective (user perception reflecting) measures
    - QoS and mobility tradeoffs