NetEx has announced [pdf] an update of its software accelerator for data over IP networks, and now claims up to 480Mbit/s - a more than 200 percent speed improvement over its previous release.

HyperIP R5 is a plug-in appliance that produces an application throughput boost of 300 percent to 1,000 percent compared to standard IP networks. Customers can do data backup/replication faster over WAN distances, lose less data in the event of an accident, and restore locally lost data faster.

HyperIP appliances run a Linux software application and are configured on each side of the WAN in pairs. They operate as a gateway for destination IP addresses, and intercept TCP packets from the application based on filtering address rules. The intercepted packets are then aggregated and compressed and sent over the network.

The speed increase depends upon two things. One is the degree of compression (the higher the compression the faster the speed increase), which depends upon the data type. The second is the TCP/IP configuration and the state of the link. Part-packet loss and latency problerms that would cause the sending and receiving applications to resend entire packets or restart the session are prevented by the appliances.

Ordinarily a TCP/IP connection can have 65KB of data in transmission at any one time. At that point it pauses until more data can be sent. But the RFC3135 standard means that long-distance links can have more data "in the air". A cross-America OC-3 link can have 1.16MB theoretically available to be in transmission. The amount of data permitted in transmission increases based on the link's bandwidth and the round-trip delay. HyperIP uses this to increase the data transmission rate.

In this example it means a sending application could pump out 17.9 times more data before it paused than with the ordinary TCP/IP configuration. The result is vastly fewer pauses when sending large amounts of data over long distances.

There are other TCP/IP characteristics, such as slow session starts and duplicate data transmission when part of a transmitted segment is lost. HyperIP compensates for these too, and so increases bandwidth use. NetEx claims to have tested and seen improvements when used with EMC's SRDF, Veritas' Volume Replicator and NSI's Double-take.