TESLA-in-SRTP%20Update

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TESLA-in-SRTP Update

• Baugher, Carrara

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TESLA-in-SRTP Version 02 (1)

• Discussion on the mailing list
• Index i taken out of TESLA MAC coverage
• Parameter list updated
• D_t added
• Name inconsistencies resolved
• Log failed verification of the safe condition

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TESLA-in-SRTP Version 02 (2)

• Spelled out presence of external MAC for DoS from
  non-members
• Optional for SRTP
• Mandatory for SRTCP
• Null packets with TESLA keys for one entire
  interval after stream stops.
• Cleaning-up

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The Key ID Information Type for the General
Extension Payload in MIKEY

• draft-carrara-newtype-keyid-00.txt

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Objective

• Define a new type in the General Extension
  Payload in MIKEY needed by MBMS
• MBMS Multimedia Broadcast/Multicast Service in
  3GPP (Rel6)
• functional freeze in December 2004
• The Streaming Scenario uses
• SRTP for media protection
• MIKEY for key mngt protocol
• MBMS requires to identify key type involved in
  the MIKEY message, and key identity

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MBMS

• Req frequent key updates
• Subscribers inconveniency to publish decryption
  keys
• 3-level key mngt
• Peer-to-peer key (MUK) shared secret
• Group key (MSK) KEK
• Traffic group key (MTK) TEK
• Frequent MTK update

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MIKEYMUKA (MSK)
MUKA
BSF
MUKB
BM-SC
MUK User Key, P2P MSK Service Key, group key
MUKB
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BSF
BM-SC
MSK
MSK
MSK
MTK Traffic Key, group key (eq. TGK/TEK)
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• General Extension Payload in MIKEY

Key ID Information