Viagenie Private Octopus Inc. AlefEdge, Inc Deep space communications involve long delays (e.g., Earth to Mars is 4-20 minutes) and intermittent communications, because of orbital dynamics. Up to now, communications have been done on a layer-2 point to point basis, with sometimes the use of relays, therefore no layer-3 networking was possible. RFC4838 reports an assessment done around 25 years ago concluding that the IP protocol stack was not suitable for deep space networking. This result lead to the definition of a new protocol stack based on a store-and-forward paradigm implemented in the Bundle Protocol(BP). More recently, space agencies are planning to deploy IP networks on celestial bodies, such as Moon or Mars, ground, and vicinity. This document revisits the initial assessment of not using IP and provides solution paths to use the IP protocol stack, from IP forwarding to transport to applications to network management, in deep space communications.