ATA over Ethernet

ATA over Ethernet (AoE) is a network protocol developed by the Brantley Coile Company, designed for simple, high-performance access of block storage devices over Ethernet networks. It is used to build storage area networks (SANs) with low-cost, standard technologies. In 2015 Coraid filed for bankruptcy, however the multitude of AoE implementations, both open source and proprietary, means AoE is still a viable technology.

Protocol description

AoE runs on layer 2 Ethernet. AoE does not use internet protocol (IP); it cannot be accessed over the Internet or other IP networks. In this regard it is more comparable to Fibre Channel over Ethernet than iSCSI.

With fewer protocol layers, this approach makes AoE fast and lightweight. It also makes the protocol relatively easy to implement, provides intrinsic security protections by virtue of its being non-routable, and offers linear scalability with high performance. The AoE specification is 12 pages compared with iSCSI's 257 pages.