MIT Communications Futures Program Evolving communications paradigms and Security Karen Sollins MIT CSAIL January 23, 2007

MIT CFP Sollins, 1/23/082 Overview: pulling on several threads Evolving communications paradigms Evolving social model Evolving security challenge

MIT CFP Sollins, 1/23/083 Communications: E2E Point-to-point –Letters/ –Telephones –TCP connections Broadcast/multicast –Print media - underneath 1:1 –Radio/TV –IP multicast From source to destination: some direct, some store-and-forward (e.g. intermediate servers)

MIT CFP Sollins, 1/23/084 Client/server: mostly E2E Remote invocation of specific server Distribution of “server”: clusters, load balancing, even some P2P systems (collaborating servers) P2P systems: each element can be both client and server

MIT CFP Sollins, 1/23/085 Intermediated communication: losing E2E Middle boxes –Forwarding (e.g. home for mobiles) –Firewall –Caching –Rendezvous (e.g. for multimedia conferencing) Beginning to break direct, realtime communication

MIT CFP Sollins, 1/23/086 It’s the content WWW and URLs Time and space separation –Not a question of when (realtime, etc.) –Not a question of where –Question of what Identification Search Pub/sub –Specification of what something is –Specification of interest or subscription –Current examples: social networking, news subscription services, …

MIT CFP Sollins, 1/23/087 Key components Information (Set of) Publishers (Set of) Subscribers Attributes: how to publish or subscribe Policies: (publisher, {attributes}) or (subscriber, {attributes}) Trust model Note: Can be simplified to achieve any of the other models, subsumes them.

MIT CFP Sollins, 1/23/088 The evolving social model: Trust and security Letter-writing: recognize handwriting Telephone: recognize voice recognize address TCP: recognize IP address Trust based on –Confidence in unmodified delivery –Confidence in correctness of source

MIT CFP Sollins, 1/23/089 And along came… (in the Internet) Forgeable addresses Forgeable IP addresses The Morris worm Viruses and other malware Business opportunities Enterprise and other organizational controls ISPs … Note: not all “bad”, just competing objectives

MIT CFP Sollins, 1/23/0810 Tussle: competing concerns Question: why do we care? –Sharing –Cooperation –Exposed contention Question: can we design for it? Question: is it monolithic? –Economics –Security –Social status –… Question: where are the control points? –Regulation –Specification –Design/implementation –Operation

MIT CFP Sollins, 1/23/0811 Security challenge: Trust model Not universal: regional, topical,…  context (e.g. Nissembaum, social networks) Not binary or pairwise: scalable, commutative, …  value-based, community-based Not immutable  evaluatable, assignable Consider: if assignable must have ability to assign “to something”. Therefore require appropriately defined identities.

MIT CFP Sollins, 1/23/0812 Advertisement (disclaimer here) The Security and Privacy Working Group: current agenda To explore the nature of identity required in an information-based communications paradigm, as a basis for examining the nature and capabilities required for trust and security