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Vint Cerf Preps Interplanetary Internet Protocol
TechFiends32 writes "After years of working with NASA to bring Internet connectivity to deep space, scientists say Vint Cerf's efforts may be nearing completion. To combat the apparent challenges of extending the Internet into space (such as meteors and weighty, high-powered antennas), Cerf and others have made significant efforts, like adjusting satellite-based IP, and working on delay-tolerant networking (DTN) to address pure IP's limitations in space. According to principal engineer at The Mitre Corp., Keith Scott, 'The 2010 goal is designed to bring DTN to a sufficient level of maturity to incorporate it into designs for robotic and human lunar exploration.'"
Phil Karn's old KA9Q implementation of TCP (for amateur radio) was designed to accommodate very long delays.
The trick is that you don't have to use TCP as your transport layer. DTN bundles can be transmitted over UDP, NORM, sneakernet, carrier pigeon, or anything else you can write a convergence layer for. Since DTN abstracts away the lower levels, each hop can use the transport layer that is most appropriate, like TCP on an internet hop, SCPS on a satellite hop, etc...
More information is available on the DTN Research Group's homepage: http://dtnrg.org.
I read the internet for the articles.
actually there is no such thing as an earthrise on the moon, as the moon does not 'rotate' in relation to it's movement around the earth. At any point on the surface of the moon facing the earth, the earth will always be in the same point in the sky, always.
Wrong.
Libration causes the visible face of the moon to oscillate slightly.
Therefore, you can see an Earthrise from certain points on the moon without being in motion relative to the moon yourself.
http://en.wikipedia.org/wiki/Libration
Your argument seems good at the surface, but it's not true!
The truth is that the Moon librates a bit (a few degrees), so there actually ARE earthrises when you are near the edge of the Earth-observable Moon surface. The Earth just doesn't do a full circle around the sky, it travels along a Lissajous figure.
Even Wikipedia is incorrect on this, at least when you look up "Earthrise".
Those who would give up liberty to obtain working drivers, deserve neither liberty nor working drivers.
Before anyone questions this: The angular span of the Moon's libration is a few times larger than the angular diameter of the Earth as seen from Moon.
Those who would give up liberty to obtain working drivers, deserve neither liberty nor working drivers.