One of the few predictions we can make with some confidence is that the global business climate will remain turbulent. Social, political and economic pressure will bring about new working practices in an endeavour to maximise the return on investment in people and working capital. Organisations will turn network-centric as computers and communications converge to play an increasingly critical role, and the information network will become a key enabler for many new applications. 

We are experiencing significant innovation in network technology, with 10 Gigabit operation, Virtual LANs, Voice-over-IP, multimedia protocols, high-speed cabling and new developments in broadband cable and wireless. Bandwidth consumption is growing fast. The explosion of Internet services and the formation of Intranets and Extranets are having a dramatic affect on traffic, and bandwidth prediction can no longer be extrapolated from historical data. 

While the business climate is expected to remain unpredictable, network infrastructure strategy is clear. Future designs must be multimedia-capable, highly scaleable, manageable, fail-safe and secure. The corporate network has become a pivotal component in business; poor performance and down-time can therefore have a devastating affect.

Claims that a low level of re-transmissions could have a devastating affect on LAN throughput prompted us to examine the mechanisms that might cause this.   The following analysis challenges the claim that just 1% packet re-transmission can reduce throughput by as much as 80% but illustrates that such claims are not without foundation. 

We will attempt to answer a number of related questions using basic technical assumptions but also by adopting a worst case scientific approach.