1. Amit Kleinmann NDS Israel IRTF - SMuG Second Meeting (Orlando) December 1998 IRTF - SMuG Second Meeting (Orlando) December 1998 Scenarios and Requirements for Business-Oriented Multicast Security

2. Motivation nSolve the most common problems nHandle issues that are most attractive to businesses

3. Anticipating Future Applications nWhy use multicast? l Save bandwidth l Save time l Save computational resources nWhen is multicast use justified? l Many users l High traffic volume nMulticast applications - practically don’t exist - chicken & egg problem

4. Multicast Applications  Multimedia streaming/Pay Per View 4 4  Data distribution 4 4 2 Software distribution 2 Content (sports, weather, etc.) 2 Finance (stock tickers) 2 News/USENET 2 E-mail distribution 2 Push applications  Network synchronization 4 4 2 DNS, Routing updates 2 Advertising and locating servers 2 Data link switching (DLSw) Application Many Participants High traffic volume  Shared whiteboards 8 8 2Not (yet) well defined applications ? ? 2 Distributed interactive games/simulation 2 Distance learning 2 Communicating with unknown/dynamic group  Multi-party audiovisual conferencing 8 4

5. Scenario Requirements Two main scenarios: l File transfer l Data streaming  Multimedia streaming/Pay Per View 4 4 8 4  Data distribution 4 4 4 4 2 Software distribution 2 Content (sports, weather, etc.) 2 Finance (stock tickers) 2 News/USENET 2 E-mail distribution, push app.  Network synchronization 4 4 4 4 2 DNS, Routing updates 2 Advertising and locating servers 2 Data link switching (DLSw) Application Many High traffic File Data participants volume transfer streaming

6. Business Models nOne to Many vs. Many(few) to Many(few) nFree vs. Monitored l Free Multicast: Channels (Public, Previews) Content (Shareware, Program Guides, Ads) l Monitored Multicast: Subscription (Streaming Video, Audio, Data) Packages (Software, Games, Audio/Video clips) Volume (bits/packets sent and/or consumed) Time (Feeds, Conferences, Lectures)

7. File Transfer nStatic (closed) group nReliable nBusiness models: l Subscription l Packages

8. Data Streaming nBusiness model l Subscription l Packages l Volume l Time nMost common l Multimedia streaming l Non-reliable nDynamic (open) group l Monitoring group members’ behavior nKey management l SMuG decision: should be separated from the actual securing of the traffic. l Synchronization between keys and content l Real time => Symmetric keys for traffic l Key period

9. Multicast Conditional Access => Contents + Users nContent management l C.A. attributes for content l Multicast content authenticated and encrypted l Users should be aware of content descriptions and schedule. nUser/Client management l Users are known/registered l User has an authenticator l User has C.A. attributes nHierarchy

10. Multicast Conditional Access: User/Client Authentication & Encryption nEach user authenticates to the Multicast server nKey exchange between user/server nSecurity entitlements nContent usage monitoring

11. Trust in User/Client nHardware tokens l Features: Tamper-resistant Cannot be replicated easily l Advantages: Distributed solution Portability nSoftware protection l Server l Client Subject to attacks (e.g., viruses) Can be replicated

12. Benefits of Smart Cards l Physical security (VLSI, OS, Memory) l Portable (identity, rights) l Secure storage (keys, certificates, entitlements) l Secure processing (crypto functions) l Non Repudiation (transactions, signatures)