ICE 615 Network Security Term Project Mid-Presentation

[ICE 615] Network Security [ Term Project Mid-Presentation ] Mutual Authentication and Key Exchange For Wireless Communications 2002. 10 (Thu) § Song-Won Lee § 20022099 § School of Engineering Song-Won Lee, 20022099, 2002. 10 (Thu) 1

[ICE 615] Network Security Contents Introduction Project Goal Preliminaries Previous Works Future Works References Song-Won Lee, 20022099, 2002. 10 (Thu) 2

[ICE 615] Network Security Introduction (1/2) Characteris tics The Wireless Communications are characterized by: ü ü Limited power of wireless devices Wireless environment limited in bandwidth Communication medium Mobility, … These constraints have prevented a adoption of cryptographic protocols to wireless networks for authentication and security. Song-Won Lee, 20022099, 2002. 10 (Thu) 3

[ICE 615] Network Security Introduction (2/2) Why Authentication Due to the mobility of a wireless terminal, the network does not have any information about the identity of the terminal until a connection is made. ü Verifying an identity ü Client(wireless device) authentication ü Host(base station) authentication Song-Won Lee, 20022099, 2002. 10 (Thu) 4

[ICE 615] Network Security Project Goal In this term-project, I would like to propose efficient Mutually Authenticated Key Exchanged Protocols, they are suitable for establishing secure communications between a low-power wireless device and a powerful base station. Song-Won Lee, 20022099, 2002. 10 (Thu) 5

[ICE 615] Network Security Preliminaries (1/3) Requireme nts Desired security features : ü Session key establishment ü Caller ID confidentiality ü Mutual authentication ü Non-repudiation of services Implementation requirements : ü Efficiency and effectiveness in terms of computational complexity, memory demand bandwidth requirement ü Minimal user interventions Song-Won Lee, 20022099, 2002. 10 (Thu) 6

[ICE 615] Network Security Preliminaries (2/3) Authentication Protocols : One-way ü Password ü Challenge/response ü Public Key Two-way (mutual authentication) : ü Trusted intermediary ü Public Key Song-Won Lee, 20022099, 2002. 10 (Thu) 7

[ICE 615] Network Security Preliminaries (3/3) Abstract Protocol using PKC A B (PKA, SKA) r. A ← {0, 1}k (PKB, SKB) r. A, Cert. A= r. B , β, SB, Cert. B= c. A ← α = EPKB(c. A) SA=ESKA(IDB , r. B , α) {0, 1}k c. B ← {0, 1}k β = EPKA(c. B) SB=ESKB(IDA , r. A , β) r. B ← {0, 1}k σ =c. A c. B Song-Won Lee, 20022099, 2002. 10 (Thu) α, SA σ =c. A c. B 8

[ICE 615] Network Security Previous Works (1/2) [Proposed by D. Wong and A. Chan] Server-specific Protocol A B KA (PKB, SKB) r. A ← {0, 1}k EKA(r. A), Cert. AB EKA(r. A, r. B , IDB ) r. B ← {0, 1}k EKA(r. B) σ=r. A r. B Before running the protocol, A first obtains a certificate from TA, given by Cert. AB =< IDA, EPKB(KA), Sig. TA(IDA, EPKB(KA))>. Song-Won Lee, 20022099, 2002. 10 (Thu) 9

[ICE 615] Network Security Previous Works (2/2) Linear Protocol A B {a 1, …, a 2 i-1, a 2 i, …, a 2 n} R Zp-1 (PKB, SKB) {ga 1, …, ga 2 i-1, ga 2 i, …, ga 2 n} Za * Cert i. A = r. B R Zp-1 r B r. A ← {0, 1}k x=EPKB(r. B) y= a 2 i-1(x r. B) + a 2 i mod (p-1) x, y σ=r. A r. B (ga 2 i-1) Eσ (x) Song-Won Lee, 20022099, 2002. 10 (Thu) x r. B ga 2 i ? g y (mod p) σ=r. A r. B 10

[ICE 615] Network Security Conclusions More efficient protocols ü The number of times to perform the cryptographic operations ü The sizes of the messages ü The total number of messages transmitted Satisfying security goals as well. Song-Won Lee, 20022099, 2002. 10 (Thu) 11

[ICE 615] Network Security Future Works ü Study on Wireless Network in more detail, with respect to security issues ü Research more of the previous related works, and figure out challenging problems ü Develop improved Authentication and Key Agreement protocols focused on efficiency and effectiveness, … Song-Won Lee, 20022099, 2002. 10 (Thu) 12

[ICE 615] Network Security References [1] M. Bellare and P. Rogaway, Entity Authentication and Key Distribution, Crypto’ 93, LNCS 773, pp. 232 -249, 1994 [2] H. Lin and L. Harn, Authentication Protocols for Personal Communication Systems, SIGCOMM’ 95 [3] D. Wong and A. Chan, Mutual Authentication and Key Exchange for Low Power Wireless Communications, IEEE MILCOM 2001 [4] M. Jakobsson and D. Pointcheval, Mutual Authentication for Low-Power Mobile Devices, FC 2001, LNCS 2339, pp. 178 -195, 2002 [5] H. Lin, L. Harn and V. Kumar, Authentication Protocols in Wireless Communications, ICAUTO ’ 95 Song-Won Lee, 20022099, 2002. 10 (Thu) 13

[ICE 615] Network Security Thanks a lot Song-Won Lee, 20022099, 2002. 10 (Thu) 14