Network Executive Software (NetEx) has announced an
update of its software accelerator for data over IP networks, and
now claims up to 48ombps - a speed increase of more than 200% over
its previous release.
HyperIP R5 is a plug-in appliance that produces an application
throughput boost of 300% to 1,000% compared to standard IP
networks. Customers can do data back-up/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 problems 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 65KBytes of data in
transmission at any one time. At that point it pauses until more
data can be sent. But the RFC3135 standard means long-distance
links can have more data "in the air". A cross-America OC-3 link
can have 1.16MBytes 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 Software's Volume
Replicator and NSI Software's Double-take.
Chris Mellorwrites for Techworld.com