WAFS - Wide Area File System
Well, it's technically easy enough to set up a scheme, a wide area file system or WAFS, whereby local and remote files can appear to be in the same 'space'. That's what the Unix Network File System does. But both it and any Windows implementation have to overcome a single, basic and real serious problem. Remote data takes far longer to arrive than local data. That's because there is network latency. It takes seconds, even minutes, for MB of data to arrive across a wide area network:- - The longer the distance the longer the delay. - The more data there is the longer the delay. - The more nack-ack messages there are in the network protocol the longer the delay. - The smaller the data transmission unit (packet) the longer the delay. According to Riverhead, WAN round trip latency is around 25 - 200ms whereas a LAN latency figure could be under 1ms, hundreds, even thousands of times less. Several suppliers are developing WAFS implementations that aim to overcome one or ...