Highly elliptical orbits can be used to provide targeted satellite coverage of locations at high latitudes. We review the history of use of these orbits for communication. How elliptical orbits can be used for broadband communication is outlined. We propose an addition of known elliptical orbits to the new equatorial O3b satellite constellation, extending O3b to cover high latitudes and the Earth's poles. We simulate the O3b constellation and compare this to recent measurement of the first real Internet traffic across the newly deployed O3b network.

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There has been a great deal of research in recent years within the general field of mobile ad hoc networks (MANET) with many proposals submitted to the IETF for consideration. Delay or Disruption Tolerant Networking (DTN) is a relatively new field for routing, concerned with networks that experience long transmission delay or periods of disruption. Military forces around the globe have applied one or the other networking paradigm with varying degrees of success to their own problems of mobility at the lower tactical level (Brigade and below). The fundamental reason for this limited success is that many of the desired tactical scenarios at this level require a network that is not exclusively ad hoc nor exclusively disrupted, but rather a network that dynamically adapts to a variety of mobility situations ranging from relatively stable, almost enterprise like, to completely disrupted. Clearly, a routing protocol that is capable of seamlessly transitioning between synchronous and asynchronous modes of operation is needed for tactical (and other) networks. This paper will outline such a protocol, called NOMAD -Native OLSR for Mobile Ad hoc and Disrupted networks.