content distribution and protocol: from hierarchical trees to distributed graphs

1
content distribution and protocol from
hierarchical trees to distributed graphs

• Jason Gaedtke
• j.gaedtke_at_cablelabs.com
• November 7, 2007

2
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

3
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

4
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) -gt decentralized (cluster)
  -gt 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)

5
business and economic considerations

• primary appeal storage, processing, and
  bandwidth cost avoidance gt90 savings
• application infrastructure is self-organizing/heal
  ing 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

6
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

7
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, IETFs P2P SIP
• video Azureus, Joost
• storage OceanStore, Ivy
• commercial content distribution Move, Grid,
  Pando, Red Swoosh (Akamai), Kontiki (VeriSign)
• gaming and virtual worlds Quazal, FTs Solipsis
• virtual economies Scrivener (Rice), Tribler
  (Harvard)

8

• appendix

9
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 RD
• 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

10
enabling technologies

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