Secure Multicast Rekeying: A Case Study for HWSW Codesign

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Secure Multicast Rekeying A Case Study for HW/SW
Codesign

• Abdulhadi Shoufan, Ralf Laue and Sorin Huss

Integrated Circuits and Systems Technische
Universität Darmstadt
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Overview

• Secure Mulitcast
• Group Rekeying
• High-Flexibility Rekeying Processor
• Usage and Instruction Set
• Architecture
• Algorithms
• HW/SW Codesign
• Results
• Summary and Outlook

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Multicast vs. Unicast
Unicast
- High computation overhead
- High communication overhead
Mulitcast
Low computation overhead
Low communication overhead
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Data Confidentiality in Secure Multicast
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Key Management in Secure Multicast
Simple Rekeying
The server shares an identity key with each
member and the group key with all members
Costs O(n)
Logical Key Hierarchy (LKH)
The server shares an identity key with each
member, a help-key with each subgroup, and the
group key with all members
Costs O(log n)
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Logical Key Hierarchy
Disjoin m5
(1) Update k4-7 and kg
kg
(2) Build rekeying submessages
k0-3
k4-7
k2-3
k0-1
k6-7
k0
k1
k2
k3
k4
k6
k7
Optimization by reducing the number of
cryptographic operations.
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Rekeying Processor
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High-Flexibility Rekeying Processor
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Join Algorithm on the HiFlexRP
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Basic Task Partitioning
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Advanced Task Partitioning
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HW/SW Codesign
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HiFlexRP vs. Related Work
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Summary Outlook

• High-Flexibility Rekeying Processor
• HW/SW Codesign vs. hCDM
• Networking the RP

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Vielen Dank für Ihre Aufmerksamkeit