Google, Inc. Google, LLC {Editor note (To be removed before publication): The high-level summary of this document is that the IANA allocates a block of IPv6 address space specifically for use in space environments. IP communication in space environments is fundamentally different from terrestrial communication; e.g., the speed-of-light RTT from Earth to Mars ranges from ~6 minutes to ~45 minutes, which means that traditional connections (e.g Telnet over TCP) won't work. For an IP stack to know that a connection will require special handling (e.g. adjusting timers, or using different protocols), it needs to know that the latency to the remote peer is going to be significantly higher than typical terrestrial latencies. By allocating a specific block of IPv6 address space for use in space environments, IP stacks can easily identify when they are communicating with a peer in space, and adjust their behavior accordingly. This document requests that the IANA allocate a block of IPv6 address space specifically for use in space environments and then delegate from that block to the existing RIRs. The RIRs can then set policies for address allocation and assignment within the space address block and make address allocations to their members from this block. This approach leverages the existing RIR systems, including their policy development processes, governance structures, and existing relationships with their members. This includes relationships with governments within their regions, thus bypassing many of the geopolitical issues, including dealing with sanctioned countries, etc. The only real change is that the RIRs would be allocating from a different block of addresses, and setting policies for that block; the overall process would be the same as it is today. This is a much simpler and more efficient approach than creating a new registry for space use, or having a single RIR manage the entire space address block, along with all of the geo-political issues that would entail. WK: This editor note seems to actually be most of the document... :-) } IP communication in space environments is fundamentally different from terrestrial communication; a primary difference is the likelihood of long round-trip times, potentially minutes or even hours, depending on the distance between the endpoints. Existing protocols are not designed for such environments and so may not work as expected. For example, TCP connections will fail due to timeouts unless IP stacks know that the remote peer is in space, and adjust their behavior accordingly. This document requests that the IANA allocate a block of IPv6 address space specifically for use in space environments, and then delegate from that block to Regional Internet Registries (RIRs) for space use. The RIRs can then set policies for address allocation and assignment within the space address block, and make address allocations to their members from this block.