OpenNOP vs Riverbed SteelHead

OpenNOP is a free, GPLv3 open-source Linux network accelerator for point-to-point, partially meshed, and full-meshed IP networks. Its stated aim is improving performance on low-speed links such as ISDN, DSL, DS1, frame-relay, and VPN circuits. Implemented functionality includes LZ compression of TCP segment payloads and peer discovery through custom TCP options added to IP packets. A heartbeat between the user-space daemon and kernel module lets the module switch to bypass mode. The manual describes inline deployment and out-of-line deployment with policy-based routing. A prebuilt appliance image is identified as the easiest installation option. Custom Linux hosts require libnfnetlink, libnetfilter_queue, and libnl, and the manual says any Linux distribution should work. The project is self-hosted, with hybrid deployment listed, and system administrators are its intended audience using a command-line interface. Features marked todo include block-based data reduction, a WCCPv2 client, CLI configuration and statistics, and a web interface. SourceForge labels the project Alpha and lists its last update as 2015-12-28.

Riverbed SteelHead has no write-up on Specifiction yet; its figures are above.