<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><br>Regarding the allocations for celestial objects, a few points.<div><br></div><div>One, the asteroid belt is more of a swamp of little regions with constantly shifting topology. I am not on first impression immediately seeing how either a singular nor diffuse allocation (per object?…) would work for managing routing complexity. The objects have relatively predictable orbits, but they’re all over the solar system. As a mesh, we know how dynamic meshes work, but it doesn’t feel on first impression like top down IP space topology would help there. Open to learning how if someone has a plan.</div><div><br></div><div>Two, a good portion of near term spaceflight is spent in transit between major locations as laid out in the plan. Would we generate transition allocations for spacecraft en route? Expanding on the problem…</div><div><br></div><div>Three, spacecraft in transit are not predictably topologically aligned in spacetime. For each pair of bodies, there are three basic and one hopelessly complex classes of transfer orbits only one of which tends towards topological alignment.</div><div><br></div><div>3 A: The minimum energy for transfer with chemical rockets is a Hohmann Transfer, a grazing elliptical orbit at particular timing of the two relative orbits, practically in a window somewhat around the optimal time and shape. That transfer window would have network topology alignment in that everything in for example the Summer 2026 transfer window from Earth to Mars are generally in flight on similar paths and times and physically nearby each other.</div><div><br></div><div>3 B: Transfer orbits using very slow, low acceleration propulsion spiral out between bodies and the spirals depend more on acceleration and relative planetary orbital speed. Existing examples include a small number of ion thruster propelled asteroid explorers. These would not topologically align for networking as one can depart and arrive at arbitrary times on unrelated paths.</div><div><br></div><div>3 C: Transfer orbits with very high velocity change propulsion evolve away from minimum energy ellipses and towards more point and shoot straight lines at the extreme, losing dependence on orbital alignment and timing etc. These would not topologically align for networking as one can similarly start and end on unrelated paths and times far apart.</div><div><br></div><div>3 D: There are a whole class of orbital transfers taking less than Hohmann minimum energy, making it up using one or more flybys (unpowered gravitational slingshot trajectories, or powered flybys using gravity and the Oberth effect to multiply the velocity change of propulsive burns near closest approach in flybys). These go from simple one flyby cases to orbits using four or more, and they’ve become standard for missions beyond the moon or Mars. These in my impression definitively don’t usefully align to topological network addressing and approach the madness of the old ones to try to follow their planning by hand.</div><div><br></div><div>None of this invalidates topological assignment for major bodies and locations such as L5. And those could logically be extended for common new interplanetary locations. But it does ruin everyone’s day for these other spacecraft in transit cases.</div><div><br></div><div>Perhaps the more complex flightpaths get an allocation into a dedicated mesh address space where figuring out where they are is necessarily not usefully simplified and dynamic approaches are necessary, at least telling routers consistently to go dig up the mesh announcements the hard way for these vehicles.</div><div><br></div><div>Another option for some of these might be encoding the orbital parameters in the address allocations somehow. With a little math that lets the sender know what direction the recipient is at a given time. Great for asteroids and possibly Hohmann transfers, but won’t work for flybys, slow acceleration, or high energy transfers though. Still a mess there.</div><div><br></div><div><br></div><div>-george </div><div><br><div dir="ltr">Sent from my iPhone</div><div dir="ltr"><br><blockquote type="cite">On Feb 19, 2026, at 1:02 PM, Tony Li <tony.li@tony.li> wrote:<br><br></blockquote></div><blockquote type="cite"><div dir="ltr"><meta http-equiv="content-type" content="text/html; charset=us-ascii"><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);">Hi,</div><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);"><br></div><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);">As part of the IETF TIPTOP working group, we are working towards enabling the Internet in outer space. We would like to direct your attention to a couple of recent Internet drafts that may be of interest:</div><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);"><br></div><div><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); display: block;"><div style="-webkit-user-select: all; -webkit-user-drag: element; display: inline-block;" class="apple-rich-link" draggable="true" role="link" data-url="https://datatracker.ietf.org/doc/draft-many-tiptop-ip-architecture/"><a style="border-radius:10px;font-family:-apple-system, Helvetica, Arial, sans-serif;display:block;-webkit-user-select:none;width:300px;user-select:none;-webkit-user-modify:read-only;user-modify:read-only;overflow:hidden;text-decoration:none;" class="lp-rich-link" rel="nofollow" href="https://datatracker.ietf.org/doc/draft-many-tiptop-ip-architecture/" dir="ltr" role="button" draggable="false" width="300"><table style="table-layout:fixed;border-collapse:collapse;width:300px;background-color:#E6E6E6;font-family:-apple-system, Helvetica, Arial, sans-serif;" class="lp-rich-link-emailBaseTable" cellpadding="0" cellspacing="0" border="0" width="300"><tbody><tr><td vertical-align="center"><table bgcolor="#E6E6E6" cellpadding="0" cellspacing="0" width="300" style="table-layout:fixed;font-family:-apple-system, Helvetica, Arial, sans-serif;background-color:rgba(230, 230, 230, 1);-apple-color-filter:initial;" class="lp-rich-link-captionBar"><tbody><tr><td style="padding:8px 0px 8px 0px;" class="lp-rich-link-captionBar-textStackItem"><div style="max-width:100%;margin:0px 16px 0px 16px;overflow:hidden;" class="lp-rich-link-captionBar-textStack"><div style="word-wrap:break-word;font-weight:500;font-size:12px;overflow:hidden;text-overflow:ellipsis;text-align:left;" class="lp-rich-link-captionBar-textStack-topCaption-leading"><a rel="nofollow" href="https://datatracker.ietf.org/doc/draft-many-tiptop-ip-architecture/" style="text-decoration: none" draggable="false"><font color="#272727" style="color: rgba(0, 0, 0, 0.847059);">An Architecture for IP in Deep Space</font></a></div><div style="word-wrap:break-word;font-weight:400;font-size:11px;overflow:hidden;text-overflow:ellipsis;text-align:left;" class="lp-rich-link-captionBar-textStack-bottomCaption-leading"><a rel="nofollow" href="https://datatracker.ietf.org/doc/draft-many-tiptop-ip-architecture/" style="text-decoration: none" draggable="false"><font color="#808080" style="color: rgba(0, 0, 0, 0.498039);">datatracker.ietf.org</font></a></div></div></td><td style="padding:6px 12px 6px 0px;" class="lp-rich-link-captionBar-rightIconItem" width="30"><a rel="nofollow" href="https://datatracker.ietf.org/doc/draft-many-tiptop-ip-architecture/" draggable="false"><img alt="ietf-logo-nor-180.png" src="cid:7AB67099-6268-4D06-9EEB-B4FBF4D3B6F0"></a></td></tr></tbody></table></td></tr></tbody></table></a></div></div><font color="#000000"><span style="caret-color: rgb(0, 0, 0);"></span></font></div><div><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);"><div class="apple-rich-link" draggable="true" role="link" data-url="https://datatracker.ietf.org/doc/draft-many-tiptop-ip-architecture/" style="-webkit-user-select: all; -webkit-user-drag: element; display: inline-block;"></div></div><div><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);"><div class="apple-rich-link" draggable="true" role="link" data-url="https://datatracker.ietf.org/doc/draft-li-tiptop-address-space/" style="-webkit-user-select: all; -webkit-user-drag: element; display: inline-block;"></div></div><font color="#000000"></font></div><font color="#000000"></font></div><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);"><div class="apple-rich-link" draggable="true" role="link" data-url="https://datatracker.ietf.org/doc/draft-many-tiptop-ip-architecture/" style="-webkit-user-select: all; -webkit-user-drag: element; display: inline-block;"></div></div><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);"><div class="apple-rich-link" draggable="true" role="link" data-url="https://datatracker.ietf.org/doc/draft-li-tiptop-address-space/" style="-webkit-user-select: all; -webkit-user-drag: element; display: inline-block;"></div></div><div><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); display: block;"><div style="-webkit-user-select: all; -webkit-user-drag: element; display: inline-block;" class="apple-rich-link" draggable="true" role="link" data-url="https://datatracker.ietf.org/doc/draft-li-tiptop-address-space/"><a style="border-radius:10px;font-family:-apple-system, Helvetica, Arial, sans-serif;display:block;-webkit-user-select:none;width:300px;user-select:none;-webkit-user-modify:read-only;user-modify:read-only;overflow:hidden;text-decoration:none;" class="lp-rich-link" rel="nofollow" href="https://datatracker.ietf.org/doc/draft-li-tiptop-address-space/" dir="ltr" role="button" draggable="false" width="300"><table style="table-layout:fixed;border-collapse:collapse;width:300px;background-color:#E6E6E6;font-family:-apple-system, Helvetica, Arial, sans-serif;" class="lp-rich-link-emailBaseTable" cellpadding="0" cellspacing="0" border="0" width="300"><tbody><tr><td vertical-align="center"><table bgcolor="#E6E6E6" cellpadding="0" cellspacing="0" width="300" style="table-layout:fixed;font-family:-apple-system, Helvetica, Arial, sans-serif;background-color:rgba(230, 230, 230, 1);-apple-color-filter:initial;" class="lp-rich-link-captionBar"><tbody><tr><td style="padding:8px 0px 8px 0px;" class="lp-rich-link-captionBar-textStackItem"><div style="max-width:100%;margin:0px 16px 0px 16px;overflow:hidden;" class="lp-rich-link-captionBar-textStack"><div style="word-wrap:break-word;font-weight:500;font-size:12px;overflow:hidden;text-overflow:ellipsis;text-align:left;" class="lp-rich-link-captionBar-textStack-topCaption-leading"><a rel="nofollow" href="https://datatracker.ietf.org/doc/draft-li-tiptop-address-space/" style="text-decoration: none" draggable="false"><font color="#272727" style="color: rgba(0, 0, 0, 0.847059);">IP Address Space for Outer Space</font></a></div><div style="word-wrap:break-word;font-weight:400;font-size:11px;overflow:hidden;text-overflow:ellipsis;text-align:left;" class="lp-rich-link-captionBar-textStack-bottomCaption-leading"><a rel="nofollow" href="https://datatracker.ietf.org/doc/draft-li-tiptop-address-space/" style="text-decoration: none" draggable="false"><font color="#808080" style="color: rgba(0, 0, 0, 0.498039);">datatracker.ietf.org</font></a></div></div></td><td style="padding:6px 12px 6px 0px;" class="lp-rich-link-captionBar-rightIconItem" width="30"><a rel="nofollow" href="https://datatracker.ietf.org/doc/draft-li-tiptop-address-space/" draggable="false"><img alt="ietf-logo-nor-180.png" src="cid:7AB67099-6268-4D06-9EEB-B4FBF4D3B6F0"></a></td></tr></tbody></table></td></tr></tbody></table></a></div></div><font color="#000000"><span style="caret-color: rgb(0, 0, 0);"></span></font></div><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);"><br></div><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);">The latter has direct implications for the ARIN community,</div><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);"><br></div><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);">I would welcome any and all comments.</div><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);"><br></div><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);">Regards,</div><div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0);">Tony</div><span>_______________________________________________</span><br><span>ARIN-PPML</span><br><span>You are receiving this message because you are subscribed to</span><br><span>the ARIN Public Policy Mailing List (ARIN-PPML@arin.net).</span><br><span>Unsubscribe or manage your mailing list subscription at:</span><br><span>https://lists.arin.net/mailman/listinfo/arin-ppml</span><br><span>Please contact info@arin.net if you experience any issues.</span><br></div></blockquote></div></body></html>