Remote observing with the Keck Telescopes

We describe the remote observing capabilities currently provided at the Keck Headquarters in Waimea (located approximately 32 km from the Keck summit and at an elevation of 850 m) as well as the subset of capabilities now available from the mainland via the Internet. The bandwidth available between the telescope and the remote observing site determines which of several remote observing software and networking architectures is most cost-effective. We describe our operational experience with several different architectures, differentiating between those used at Keck headquarters and those used for remote observing from the mainland. Methods for optimizing bandwidth are explored, including the pipelining of image readout with data compression and transmission to the remote site. Tradeoffs between network bandwidth, security, and portability of software to remote observing sites are also explored.