Gigabit Ethernet

As the amount of data that needed to be backed up grew exponentially, backup software became more and more efficient. Advanced features like dynamic parallelism and software compression made backing up such large amounts of data possible. However, the amount of data on a single server became so large that it could not be backed up over a normal LAN connection. Even if the LAN were based on ATM, only so many bits can be sent over such a wire. (This is why I believe that 2000 will be the year of the SAN. For more information on SANs, read Chapter 5.)

Gigabit Ethernet was supposed to save the backup world. Ten times faster than its closest cousin (Fast Ethernet), surely it would solve the bandwidth problem. Many people, including me, designed large backup systems with gigabit Ethernet in mind. Unfortunately, we were often disappointed. While a gigabit Ethernet connection could support 1000 Mb/s between switches, maintaining such a speed between a backup client and backup server was impossible. The number of interrupts required to support gigabit Ethernet consumed all available resources on the servers involved.[97] Even after all available CPU and memory had been exhausted, the best you could hope for was 300 Mb/s. While transferring data at this speed, the systems could do nothing else. This meant that under normal conditions, the best you would get was around 200 Mb/s.

One company believes it has the solution for this problem. Alteon Networks (http://www.alteon.com ...

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