[arin-ppml] Addressing for other planets

[John Curran]

On Mar 2, 2026, at 11:53 AM, Tony Li <tony.li at tony.li> wrote:

Hi John,

Perfectly sensible – and similar to what space agencies would are likely do if they were to receive their own allocation: allocating one prefix per body internally to allow per-body aggregation, and issuing space to projects based on the most expected celestial body of operation.

Unfortunately, that’s not what’s happening.  I’m told that agencies are picking random IPv4 prefixes from their normal assignments, without any thought to aggregation, either internally or cross-agency.

If agencies are currently picking random IPv4 prefixes from their normal assignments, then that is indeed unfortunate – particularly since optimization of routing traffic will inevitably involve some carefully consideration of aggregation options and network architecture choices

(regardless of whether provider topological or celestial-body based.)

We need this draft and corresponding RIR policies to take back to them and help them with aggregation.

It’s clear that some guidance is needed, but again, it appears that there are multiple approaches that such guidance could take; e.g.  establishment of a deep-space general purpose address range with provider-based allocations would also resolve the situation of agencies picking address space at random – and that is regardless of whether celestial-body topological considerations were incorporated into the accompanying allocation policy.

But of course that also means that if providers instead received their own aggregate blocks for all all activities  – regardless of celestial location – then under normal circumstances each provider would advertise a single covering aggregate across the deep space Internet. Aggregation would follow provider infrastructure, similar to terrestrial ISP models.

That works if and only if the topology is agency exclusive.

If, on the other hand, the agencies share infrastructure, as is now being proposed, it means that routing will need to carry per-mission prefixes throughout the infrastructure, as the topology no longer aligns with addressing.

Indeed – as I noted, the "actual operational aggegation and net routing load would be quite sensitive to number of celestial-body interconnects that end up in routine operation."

It does seem like the actual operational aggegation and net routing load would be quite sensitive to number of celestial-body interconnects that end up in routine operation – and that celestial-body-based allocation would in normal circumstances require each provider to carry N routes (N being number of celestial body-assigned allocations it received) on its own network both internally and to shared with others to maintain full connectivity.

That is correct.  Aggregation is sensitive to topology.  If the topology is provider-exclusive, then you would want to aggregate that way.  However, if the topology is provider-shared, then you would want to aggregate geographically.

Very challenging to perform any real optimization in advance absent some firmer planning assumptions, as either approach could easily end up being remarkably  sub-optimal.

The challenge with that is that we end up doing effectively random allocation and completely lose out on the ability to aggregate.  The primary purpose of all addressing is to make routing efficient, and it seems like we would be well served to take this opportunity to not repeat previous inefficiencies.

You suggest that a model where each space agency gets its own aggregate block for all its missions is effectively random allocation?? Could you elaborate on that?

Today, through lack of suitable authoritative direction, each agency is acting independently and allocating per-mission prefixes without any thought to aggregation, internally or externally.  One can hardly blame them, as this is well outside of the mission scope and expertise.

Are you suggesting that the community provide authoritative network architecture direction to the deep space agency networks?   (Yes, mandating a specific addressing plan which could result in highly suboptimal routing absent corresponding architectural decisions – i.e. celestial-body interconnections and transit – does indeed equate to providing binding architectural direction...)

Provider-based allocation allows naturally for aggregation across infrastructure – as you are aware, the IPv4 “swamp" referenced in the draft is a result of provider-independent (PI) assignments for terminus networks – many being made pre-CIDR era, and others due to provider-independent allocation policies at the RIRs since…    I guess the question is whether we expect a lot of requests for IP address space that not affiliated with any deep space network - do you have an estimate?

Provider-based allocation allows for natural aggregation if there is a provider-based topology.  Provider-shared topologies break that natural aggregation.

100% agreed - provider-shared topologies do have very distinct architectural and mission implications – but the mandate of the Internet Numbers Community to establish binding requirements of this nature (particularly on others not directly involved in the deliberations) certainly warrants some careful consideration by this community.

Thanks,
/John

John Curran
President and CEO
American Registry for Internet Numbers



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