content distribution and “protocol”: from hierarchical trees to distributed graphs Jason Gaedtke November 7, 2007

abstract codec efficiency advances, recording device and storage commoditization, and broadband access network maturity have enabled an explosion in the consumption of professional and user-generated IP video traditional media distributors and emerging Internet providers are challenged to drive cost from their IP video business models the P2P architectural paradigm and the philosophical and cultural concept of “Protocol” offer a compelling alternative to traditional, hierarchical CDNs

definition (Galloway, MIT Press 2004) “protocol” – a system of distributed management/control strategies – facilitates P2P relationships between autonomous entities – anti-hierarchical and anti-authority – engenders localized decision-making, versus centralized – accommodates massive contingency/change – represents the outcome (not the antecedent) of distributed behavior analysis occurs at the intersection of philosophy, culture and technology control moves from authorities to protocol standards

philosophical and political considerations mesh vs. hierarchy – favors horizontal, distributed organization and control – e.g. TCP/IP vs. DNS (hindered by points of control/failure) – end-to-end principal: state/intelligence at the edges historical movement – centralized (server) -> decentralized (cluster) -> distributed (net) – low barrier-to-entry empowers participation, breeds innovation – a similar decentralized/distributed control model underlies proven and successful open source collaboration this concept, Protocol, is native to the logical design/architecture of the Internet (TCP/IP) – infrastructure and associated corporate capital investment notwithstanding (i.e., root of present Net Neutrality debate)

business and economic considerations primary appeal: storage, processing, and bandwidth cost avoidance; >90% savings – application infrastructure is self-organizing/healing; minimal admin/ops overhead must consider/provide user value-proposition (beyond “free content”) motivating participation and resource contribution Internet public policy and intellectual property law/enforcement still evolving growing need for security and data integrity assurances

technical considerations P2P substrates: form a decentralized, self-organizing and fault-tolerant overlay network provide efficient request routing, deterministic object location, and load-balancing in an application-independent manner facilitate application-specific object replication, caching, and fault recovery enable robust and efficient data and service availability, reliability and geographical/route diversity and redundancy offer compelling scaling features and performance typically O(log(N)) participatory design, development and control model engenders innovation

applications substantial academic and corporate research over the past five+ years horizontal, mesh networks and P2P applications evolving beyond file-sharing – music/movies/tv “sharing”: Napster, Gnutella, KaZaA, eDonkey, FreeNet, BitTorrent – voice: Skype, IETF’s P2P SIP – video: Azureus, Joost – storage: OceanStore, Ivy – commercial content distribution: Move, Grid, Pando, Red Swoosh (Akamai), Kontiki (VeriSign) – gaming and virtual worlds: Quazal, FT’s Solipsis – virtual economies: Scrivener (Rice), Tribler (Harvard)

appendix

research and references “Protocol: How Control Exists after Decentralization” – Alex Galloway (NYU) – MIT Press, 2004 – Philosophical foundations in Marx, Foucault, Deleuze, Jameson, Hardt academic research – Berkeley (OceanStore persistence) – Columbia (P2P SIP audio/video communications) – MIT (Chord DHT, Ivy file-system) – Purdue (Pastry, Dynamic P2P Source Routing) – Rice (FreePastry, Squirrel web cache) – Washington (Pastry, BitTyrant) corporate R&D – France Telecom (Solipsis virtual world, Maay search engine, – Microsoft (Herald pub/sub, SimPastry, PAST archive, SplitStream CDN) Distributed Computing Industry Association (DCIA) P4P Working Group – Explicit Communications for Cooperative Control Between P2P and Network Providers IETF P2P SIP looking to add CableLabs to this list

enabling technologies reliable and efficient storage, search and discovery algorithms – DHTs: Chord, CAN, Pastry, Tapestry identity reputation security virtual economy quality of service multicast