Skip to main content
Log in

Fixed points of rational functions satisfying the Carlitz property

  • Original Paper
  • Published:
Applicable Algebra in Engineering, Communication and Computing Aims and scope

Abstract

Recent research within the field of cryptography has suggested that S-boxes should be chosen to contain few fixed points, motivating analysis of the fixed points of permutations. This paper presents a novel mean of obtaining fixed points for all functions satisfying a property put forth by Carlitz. We determine particular results concerning the fixed points of rational functions. Such concepts allow the derivation of an algorithm which cyclically generates fixed points for all three classes of functions satisfying the Carlitz property, the most renowned of which are Rédei rational functions. Specifically, we present all fixed points for any given Rédei function in a single cycle, generated by a particular non-constant rational transformation. For the other two classes of functions, we present their fixed points in cycles consisting of smaller cycles of fixed points. Finally, we provide an explicit expression for the fixed points of all Rédei functions over \({\mathbb {F}}_q\).

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save

Springer+ Basic
$34.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or eBook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1

Similar content being viewed by others

Explore related subjects

Discover the latest articles, news and stories from top researchers in related subjects.

References

  1. Barbero, S., Cerruti, U., Murru, N.: Solving the Pell equation via Rédei rational functions. Fibonacci Q. 48(4), 348–357 (2010)

    MATH  Google Scholar 

  2. Bellini, E., Murru, N.: An efficient and secure RSA-like cryptosystem exploiting Rédei rational functions over conics. Finite Fields Appl. 39, 179–194 (2016)

    Article  MathSciNet  Google Scholar 

  3. Carlitz, L.: A note on permutation functions over a finite field. Duke Math. J. 29(2), 325–332 (1962)

    Article  MathSciNet  Google Scholar 

  4. Cesmelioglu, A., Meidl, W., Topuzoglu, A.: On the cycle structure of permutation polynomials. Finite Fields Appl. 14(3), 593–614 (2008)

    Article  MathSciNet  Google Scholar 

  5. Charpin, P., Mesnager, S., Sarkar, S.: Dickson polynomials that are involutions. In: Canteaut, A., Effinger, G., Huczynska, S., Panario, D., Storme, L. (eds.) Contemporary Developments in Finite Fields and Applications, pp. 22–47. World Scientific Publishing, Singapore (2016)

    Chapter  Google Scholar 

  6. Charpin, P., Mesnager, S., Sarkar, S.: Involutions over the Galois field \({\mathbb{F}}_{2^n}\). IEEE Trans. Inf. Theory 62(4), 2266–2276 (2016)

    Article  Google Scholar 

  7. Chubb, K.: Fixed Points of Rational Functions Satisfying the Carlitz Property. M.Sc. Thesis, Carleton University (2018)

  8. Gutierrez, J., Winterhof, A.: Exponential sums of non-linear congruential pseudorandom number generators with Rédei functions. Finite Fields Appl. 14(2), 410–416 (2008)

    Article  MathSciNet  Google Scholar 

  9. Kameswari, P.A., Kumari, R.C.: Cryptosystem with Rédei rational functions via Pell conics. Int. J. Comput. Appl. 54(15), 1–6 (2012)

    Google Scholar 

  10. Lidl, R., Niederreiter, H.: Finite Fields, 2nd edn. Cambridge University Press, Cambridge (1997)

    MATH  Google Scholar 

  11. Nobauer, R.: Cryptanalysis of the Rédei scheme. Contributions to General Algebra, vol. 3, pp. 255–264. Teubner, Vienna (1984)

    Google Scholar 

  12. Panario, D., Sadeghi, M., Sakzad, A.: Cycle structure of permutation functions over finite fields and their applications. Adv. Math. Commun. 6(3), 347–361 (2012)

    Article  MathSciNet  Google Scholar 

  13. Qureshi, C., Panario, D.: Rédei actions on finite fields and multiplication map in cyclic group. SIAM J. Discrete Math. 29(3), 1486–1503 (2015)

    Article  MathSciNet  Google Scholar 

  14. Rubio, I., Pacheco-Tallaj, N., Corrada-Bravo, C., Castro, F.: Explicit formulas for monomial involutions over finite fields. Adv. Math. Commun. 11(2), 301–306 (2017)

    Article  MathSciNet  Google Scholar 

  15. Wang, Q.: A note on inverses of cyclotomic mapping permutation polynomials over finite fields. Finite Fields Appl. 45, 422–427 (2017)

    Article  MathSciNet  Google Scholar 

  16. Wu, B., Liu, Z.: Linearized polynomials over finite fields revisited. Finite Fields Appl. 22, 79–100 (2013)

    Article  MathSciNet  Google Scholar 

  17. Youssef, A., Tavares, S., Heys, H.: A new class of substitution-permutation networks. In: Proceedings of Selected Areas in Cryptography, SAC-96, pp. 132–147 (1996)

Download references

Acknowledgements

This work served as partial fulfillment of the requirements for a Master of Science in Mathematics by the first author [7], and was conducted under the supervision of the latter two authors. The second and third authors are partially funded by NSERC of Canada. We also thank the anonymous referees for their helpful suggestions.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Qiang Wang.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Appendices

Appendices

Let \(q=p^t\), \(a \in {\mathbb {F}}_q\), and \(\Phi \in {\mathbb {F}}_{q^2}\), with \(a = \Phi ^2\). Algorithms for producing all of the fixed points in \({\mathbb {F}}_q\) for functions f satisfying the Carlitz property are given in [7]. In the following, we give sample outputs from these algorithms.

1.1 A: Sample fixed points for Type-1 functions

See Table 1.

Table 1 List of the N fixed points for f a Type-1 function with \(a=0\) and \(q=p^t\)

1.2 B: Sample fixed points for Rédei functions

See Tables 2 and 3.

Table 2 List of the N fixed points for sample Rédei functions with a square
Table 3 List of the N fixed points for sample Rédei functions with a non-square. The fixed points are represented in \({\mathbb {F}}_{q^2}\) but exist in \({\mathbb {F}}_q\)

1.3 C: Sample fixed points for Type-3 functions

See Table 4.

Table 4 List of the N fixed points for f a Type-3 function with \(a \ne 0\) and \(q=2^t\)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Chubb, K., Panario, D. & Wang, Q. Fixed points of rational functions satisfying the Carlitz property. AAECC 30, 417–439 (2019). https://doi.org/10.1007/s00200-019-00382-2

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00200-019-00382-2

Keywords