Solutions

In-Band TCP Acceleration

Anagran can instantly accelerate TCP traffic via optional advanced in-band rate signaling. The figure below illustrates a TCP/IP application over a secure satellite link. Conventional IPv4-capable satellite base stations compensate for the high error rate and long delay of a satellite connection by locally spoofing TCP acknowledgements. This requires access to the TCP header. With IPv6, the TCP header is encrypted and thereby completely concealed, thus requiring another approach.

For any high delay path (cross U.S. or trans-ocean) the round trip delay reduces TCP throughput considerably. High error rate paths such as wireless links also cause TCP to lose throughput. With an error rate of 20% TCP throughput nears zero. The Anagran advanced in-band rate signaling protocol improves TCP block delivery time and throughput in both cases, by separating the network congestion issue from the link errors and allowing the available end-to-end network rate to be communicated back to the sender. The figure below shows the impact on TCP delivery time for a 1 megabyte page using this advanced QoS signaling and receiving approval for 32 Mbps.