Optimal Dispersal of Certificate Chains

  • Eunjin Jung
  • Ehab S. Elmallah
  • Mohamed G. Gouda
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3274)


We consider a network where users can issue certificates that identify the public keys of other users in the network. The issued certificates in a network constitute a set of certificate chains between users. A user u can obtain the public key of other user v from a certificate chain from u to v in the network. For the certificate chain from u to v, u is called the source of the chain and v is called the destination of the chain. Certificates in each chain are dispersed between the source and destination of the chain such that the following condition holds. If any user u needs to securely send messages to any other user v in the network, then u can use the certificates stored in u and v to obtain the public key of v (then u can use the public key of v to set up a shared key with v to securely send messages to v). The cost of dispersing certificates in a set of chains among the source and destination users in a network is measured by the total number of certificates that need to be stored in all users. A dispersal of a set of certificate chains in network is optimal if no other dispersal of the same chain set has a strictly lower cost. In this paper, we show that the problem of computing optimal dispersal of a given chain set is NP-Complete. We also present three polynomial-time algorithms that compute optimal dispersals for three special classes of chain sets.


Source Node Destination Node Vertex Cover Distribute Hash Table Concise Graph 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Eunjin Jung
    • 1
  • Ehab S. Elmallah
    • 2
  • Mohamed G. Gouda
    • 1
  1. 1.Department of Computer SciencesThe University of Texas at AustinAustinUSA
  2. 2.Department of Computing ScienceUniversity of AlbertaEdmontonCanada

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