Efficient and Quantum-safe Internet Key Exchange Protocols for Satellite Communications

Alessandro Cammarano; Daniele Romano; Davide De Zuane; Gr\'egoire Anchelergues; Juan Jos\'e Grosso; Marco Baldi; Paolo Santini

arxiv: 2605.28660 · v1 · pith:N2VOY4JYnew · submitted 2026-05-27 · 💻 cs.CR · cs.NI

Efficient and Quantum-safe Internet Key Exchange Protocols for Satellite Communications

Davide De Zuane , Marco Baldi , Paolo Santini , Gr\'egoire Anchelergues , Daniele Romano , Alessandro Cammarano , Juan Jos\'e Grosso This is my paper

Pith reviewed 2026-06-29 11:32 UTC · model grok-4.3

classification 💻 cs.CR cs.NI

keywords satellite communicationsInternet Key Exchangepost-quantum cryptographyhybrid cryptographyquantum resistanceresource constraintskey exchange protocols

0 comments

The pith

Variants of the Internet Key Exchange protocol can be adapted to deliver both low complexity and quantum resistance for satellite communications.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper investigates how the standard Internet Key Exchange protocol can be modified for satellite networks, where onboard resources are limited and transmission delays are long. It defines and evaluates several protocol variants that incorporate post-quantum primitives or hybrid combinations of classical and post-quantum methods. A sympathetic reader would care because satellite links are vulnerable to harvest-now-decrypt-later attacks once quantum computers mature, and any solution must avoid overloading constrained terminals. The work approaches the problem through both design choices and experimental measurements to show that efficiency and quantum safety can be achieved together.

Core claim

The paper claims that specific variants of the Internet Key Exchange protocol, when designed with low-complexity post-quantum or hybrid cryptographic primitives, meet the resource and latency requirements of satellite terminals while providing resistance to quantum attackers, as confirmed by experimental assessment.

What carries the argument

IKE protocol variants that combine classical and post-quantum primitives, evaluated for bandwidth use, processing load, and quantum resistance in satellite settings.

If this is right

Satellite systems can perform key exchange without excessive overhead even when using quantum-resistant methods.
Hybrid cryptographic solutions allow a gradual shift from classical to post-quantum primitives without breaking existing deployments.
The assessed variants directly address harvest-now-decrypt-later risks in long-lived satellite links.
Experimental results provide concrete data on the trade-offs between complexity and security for constrained environments.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

Similar protocol adjustments could extend to other high-latency constrained links such as deep-space or underwater communications.
The hybrid approach suggests a practical path for updating standards that already rely on IKE in mixed terrestrial-satellite networks.
Further validation would require testing the variants under actual orbital conditions rather than simulated latency.

Load-bearing premise

The defined protocol variants can be implemented and tested in ways that simultaneously satisfy low complexity, quantum resistance, and the constraints of satellite terminals.

What would settle it

An experiment or deployment measurement in which one or more proposed variants exceeds the available processing power, bandwidth, or latency budget of a representative satellite terminal while still claiming quantum resistance.

Figures

Figures reproduced from arXiv: 2605.28660 by Alessandro Cammarano, Daniele Romano, Davide De Zuane, Gr\'egoire Anchelergues, Juan Jos\'e Grosso, Marco Baldi, Paolo Santini.

**Figure 2.** Figure 2: LW3 exchange flow. Both peers encapsulate a fresh nonce under [PITH_FULL_IMAGE:figures/full_fig_p005_2.png] view at source ↗

**Figure 3.** Figure 3: Communication architecture through a satellite network. [PITH_FULL_IMAGE:figures/full_fig_p005_3.png] view at source ↗

**Figure 5.** Figure 5: Total communication cost for the considered protocol variants. [PITH_FULL_IMAGE:figures/full_fig_p006_5.png] view at source ↗

read the original abstract

This paper studies cryptographic key exchange in satellite communications, which requires specific solutions because the satellite context presents unique challenges, particularly concerning onboard resource constraints and long transmission latency. We address these challenges by considering the Internet Key Exchange (IKE) protocol, which is widely used in terrestrial networks, and studying its applicability in the satellite context. This requires addressing two main issues: i) its efficiency in terms of the resources and bandwidth required to adapt to satellite terminals, and ii) its resistance even to attackers equipped with a quantum computer, in order to resist obsolescence and defend against harvest-now-decrypt-later attacks. We study these aspects from both a design and experimental point of view, defining and assessing some protocol variants characterized by low complexity and quantum resistance. To address the need to manage the transition from classic cryptographic primitives to post-quantum ones, we also consider the possibility of using hybrid cryptographic solutions that combine them both.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Desk Editor's Note private letter to a colleague

Applies hybrid post-quantum ideas to IKE for satellites and runs some experiments on variants, but the abstract gives no concrete numbers on efficiency or latency gains.

read the letter

The main point is that this paper takes standard IKE, tweaks it for satellite links with their resource limits and high latency, and looks at hybrid classical-plus-post-quantum versions to handle the shift to quantum resistance. They define a few protocol variants and say they assessed them from both design and experimental angles for low complexity.

What stands out as useful is the focus on real constraints: satellites cannot afford heavy computation or many round trips, and there is a need to guard against harvest-now-decrypt-later attacks. Considering hybrids makes sense for a transition period rather than a sudden switch.

The soft spots are the missing details. The write-up stays at a high level with no protocol diagrams, no equations for message sizes or computation costs, and no reported measurements on bandwidth, CPU time, or latency under satellite conditions. Without those numbers it is hard to tell whether the variants actually deliver lower complexity than existing options or whether the experiments used realistic terminal hardware. The soundness score is low for exactly this reason.

This paper is for engineers and researchers who build or secure satellite networks and need practical ways to add quantum resistance without breaking current systems. A reader already working on constrained post-quantum crypto might pick up the specific variants they chose and the hybrid approach.

It deserves a serious referee because the application area matters for infrastructure and the authors appear to engage directly with the stated constraints rather than overclaiming. Even if the contribution is mostly engineering adaptation, the topic is timely enough to warrant review, provided the full paper supplies the quantitative results that are absent from the abstract.

Referee Report

1 major / 0 minor

Summary. The paper studies cryptographic key exchange in satellite communications by adapting the Internet Key Exchange (IKE) protocol to address onboard resource constraints and long transmission latency. It focuses on two issues: efficiency in resources and bandwidth, and resistance to quantum computers to counter harvest-now-decrypt-later attacks. The work defines and experimentally assesses low-complexity quantum-resistant IKE variants and considers hybrid classical/post-quantum solutions for the transition period.

Significance. If the experimental assessments of the variants hold, the paper could offer practical insights for deploying quantum-safe key exchange in resource-constrained satellite environments, supporting the shift to post-quantum cryptography while managing latency and bandwidth limits.

major comments (1)

[Abstract] Abstract: The abstract provides only a high-level description with no mathematical formulations, protocol definitions, experimental setup, performance metrics, error analysis, or results. This makes it impossible to assess whether the claimed low-complexity quantum-resistant variants and hybrids meet the satellite constraints or support the central claims.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for their review and the opportunity to clarify our work. We address the single major comment below.

read point-by-point responses

Referee: [Abstract] Abstract: The abstract provides only a high-level description with no mathematical formulations, protocol definitions, experimental setup, performance metrics, error analysis, or results. This makes it impossible to assess whether the claimed low-complexity quantum-resistant variants and hybrids meet the satellite constraints or support the central claims.

Authors: We agree that the current abstract is high-level and lacks the specific elements noted. In the revised manuscript we will expand the abstract to incorporate: (i) the core mathematical formulation of the hybrid key-exchange construction, (ii) concise definitions of the two low-complexity quantum-resistant IKE variants, (iii) the satellite-specific experimental parameters (on-board CPU/memory budgets, round-trip latency model, and bandwidth constraints), (iv) the primary performance metrics (handshake latency, message sizes, CPU cycles) together with a brief statement of the observed error margins, and (v) the headline quantitative results. These additions will remain within the journal’s word limit while enabling an immediate assessment of the claims. revision: yes

Circularity Check

0 steps flagged

No significant circularity in protocol design claims

full rationale

The paper describes defining and experimentally assessing IKE protocol variants for satellite constraints, including hybrid classical/post-quantum options. No equations, derivations, fitted parameters presented as predictions, or self-citation chains appear in the abstract or description. The work centers on practical design choices and evaluations rather than any claimed first-principles reduction or uniqueness theorem, making the central claims self-contained against external benchmarks with no load-bearing circular steps.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

Abstract provides no information on parameters, axioms, or new entities.

pith-pipeline@v0.9.1-grok · 5733 in / 862 out tokens · 54937 ms · 2026-06-29T11:32:19.839457+00:00 · methodology

discussion (0)

Reference graph

Works this paper leans on

11 extracted references

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2026
[2]

Mixing Preshared Keys in the Internet Key Exchange Protocol Version 2 (IKEv2) for Post-quantum Security,

S. Fluhrer, P. Kampanakis, D. McGrew, and V . Smyslov, “Mixing Preshared Keys in the Internet Key Exchange Protocol Version 2 (IKEv2) for Post-quantum Security,” RFC 8784, Jun. 2020. [Online]. Available: https://www.rfc-editor.org/info/rfc8784

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[3]

Multiple Key Exchanges in the Internet Key Exchange Protocol Version 2 (IKEv2),

C. Tjhai, M. Tomlinson, G. Bartlett, S. Fluhrer, D. V . Geest, O. Garcia-Morchon, and V . Smyslov, “Multiple Key Exchanges in the Internet Key Exchange Protocol Version 2 (IKEv2),” RFC 9370, May
[4]

Available: https://www.rfc-editor.org/info/rfc9370

[Online]. Available: https://www.rfc-editor.org/info/rfc9370
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Post-quantum Key Exchange with ML-KEM in the Internet Key Exchange Protocol Version 2 (IKEv2),

P. Kampanakis, “Post-quantum Key Exchange with ML-KEM in the Internet Key Exchange Protocol Version 2 (IKEv2),” Internet Engineering Task Force, Internet-Draft draft-ietf-ipsecme-ikev2-mlkem- 04, Feb. 2026, work in Progress. [Online]. Available: https: //datatracker.ietf.org/doc/draft-ietf-ipsecme-ikev2-mlkem/04/

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[6]

Minimal Internet Key Exchange Version 2 (IKEv2) Initiator Implementation,

T. Kivinen, “Minimal Internet Key Exchange Version 2 (IKEv2) Initiator Implementation,” RFC 7815, Mar. 2016. [Online]. Available: https://www.rfc-editor.org/info/rfc7815

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Performance evaluation of quantum-resistant IKEv2 protocol for satellite networking environ- ments,

A. Mutlugun, Y . Hanna, and K. Akkaya, “Performance evaluation of quantum-resistant IKEv2 protocol for satellite networking environ- ments,” in2024 IEEE Virtual Conference on Communications (VCC), 2024, pp. 1–7

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IP Payload Compression Protocol (IPComp),

A. Shacham, M. Thomas, R. Monsour, and R. Pereira, “IP Payload Compression Protocol (IPComp),” RFC 2393, Dec. 1998. [Online]. Available: https://www.rfc-editor.org/info/rfc2393

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The RObust Header Compression (ROHC) Framework,

L.-E. Jonsson, K. Sandlund, and G. Pelletier, “The RObust Header Compression (ROHC) Framework,” RFC 5795, Mar. 2010. [Online]. Available: https://www.rfc-editor.org/info/rfc5795

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E. Crockett, C. Paquin, and D. Stebila, “Prototyping post-quantum and hybrid key exchange and authentication in tls and ssh,”Cryptology ePrint Archive, 2019

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[11]

Signature Authentication in the Internet Key Exchange Version 2 (IKEv2),

T. Kivinen and J. Snyder, “Signature Authentication in the Internet Key Exchange Version 2 (IKEv2),” RFC 7427, Jan. 2015. [Online]. Available: https://www.rfc-editor.org/info/rfc7427

2015

[1] [1]

Implementation and transition to post-quantum cryptography of the minimal IKE protocol,

D. De Zuane, P. Santini, and M. Baldi, “Implementation and transition to post-quantum cryptography of the minimal IKE protocol,” Glasgow, UK, May 2026, to be presented at the IEEE International Conference on Communications (ICC) 2026

2026

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Mixing Preshared Keys in the Internet Key Exchange Protocol Version 2 (IKEv2) for Post-quantum Security,

S. Fluhrer, P. Kampanakis, D. McGrew, and V . Smyslov, “Mixing Preshared Keys in the Internet Key Exchange Protocol Version 2 (IKEv2) for Post-quantum Security,” RFC 8784, Jun. 2020. [Online]. Available: https://www.rfc-editor.org/info/rfc8784

2020

[3] [3]

Multiple Key Exchanges in the Internet Key Exchange Protocol Version 2 (IKEv2),

C. Tjhai, M. Tomlinson, G. Bartlett, S. Fluhrer, D. V . Geest, O. Garcia-Morchon, and V . Smyslov, “Multiple Key Exchanges in the Internet Key Exchange Protocol Version 2 (IKEv2),” RFC 9370, May

[4] [4]

Available: https://www.rfc-editor.org/info/rfc9370

[Online]. Available: https://www.rfc-editor.org/info/rfc9370

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Post-quantum Key Exchange with ML-KEM in the Internet Key Exchange Protocol Version 2 (IKEv2),

P. Kampanakis, “Post-quantum Key Exchange with ML-KEM in the Internet Key Exchange Protocol Version 2 (IKEv2),” Internet Engineering Task Force, Internet-Draft draft-ietf-ipsecme-ikev2-mlkem- 04, Feb. 2026, work in Progress. [Online]. Available: https: //datatracker.ietf.org/doc/draft-ietf-ipsecme-ikev2-mlkem/04/

2026

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Minimal Internet Key Exchange Version 2 (IKEv2) Initiator Implementation,

T. Kivinen, “Minimal Internet Key Exchange Version 2 (IKEv2) Initiator Implementation,” RFC 7815, Mar. 2016. [Online]. Available: https://www.rfc-editor.org/info/rfc7815

2016

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Performance evaluation of quantum-resistant IKEv2 protocol for satellite networking environ- ments,

A. Mutlugun, Y . Hanna, and K. Akkaya, “Performance evaluation of quantum-resistant IKEv2 protocol for satellite networking environ- ments,” in2024 IEEE Virtual Conference on Communications (VCC), 2024, pp. 1–7

2024

[8] [8]

IP Payload Compression Protocol (IPComp),

A. Shacham, M. Thomas, R. Monsour, and R. Pereira, “IP Payload Compression Protocol (IPComp),” RFC 2393, Dec. 1998. [Online]. Available: https://www.rfc-editor.org/info/rfc2393

1998

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The RObust Header Compression (ROHC) Framework,

L.-E. Jonsson, K. Sandlund, and G. Pelletier, “The RObust Header Compression (ROHC) Framework,” RFC 5795, Mar. 2010. [Online]. Available: https://www.rfc-editor.org/info/rfc5795

2010

[10] [10]

Prototyping post-quantum and hybrid key exchange and authentication in tls and ssh,

E. Crockett, C. Paquin, and D. Stebila, “Prototyping post-quantum and hybrid key exchange and authentication in tls and ssh,”Cryptology ePrint Archive, 2019

2019

[11] [11]

Signature Authentication in the Internet Key Exchange Version 2 (IKEv2),

T. Kivinen and J. Snyder, “Signature Authentication in the Internet Key Exchange Version 2 (IKEv2),” RFC 7427, Jan. 2015. [Online]. Available: https://www.rfc-editor.org/info/rfc7427

2015