7DS Peer-to-Peer Information Dissemination and Prefetching Architecture

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7DSPeer-to-Peer Information Dissemination and
Prefetching Architecture

• Stelios Sidiroglou-Douskos
• CS Seminar Timo Ojala
• June 10, 2004

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What is 7ds?

• Message-based application-layer service
• propagates information objects among mobile nodes
  that are within high-speed wireless range
• Carry data using mobile nodes
• To and from infrastructure networks
• Scales with the user population in a given area
• No infrastructure planning or deployment

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7DS approach

• Data sharing among mobile hosts in a  peer to
  peer fashion.
• 7DS can coexist with other methods for data
  access, e.g. via FIS or BS to the Internet.
• 7DS as extension of infrastructure and ad-hoc
  networks

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7ds applications

• Wireless web caching
• Cheaper, faster links
• Emergency Infrastructure
• Im alive messages, rescue info
• Wireless peer-to-peer sharing
• Maps, schedules, email
• Wireless mobile sensors
• Too far to directly communicate
• Vehicle Transportation
• Leverage local data

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Basic idea

• Device wants to get an object
• Web page, map, local weather
• Obtain from peer within range
• Periodically query for object
• Device wants to send an object
• Email, SMS, I-am-alive
• Pass to nearby peer

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Architecture

• Data access engine
• 802.11, Bluetooth
• Cache manager
• Content cache, reputation, popularity
• Search engine
• Keyword searching, indexing
• Decision maker
• Periodic, power-save, forwarding

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7ds Architecture
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HTTP Architecture
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Communication Protocol
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Example
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Object Relay

• Periodically advertise presence
• Relay location-based information (velocity,
  destination, available buffer size)
• Select candidate nodes to relay message
• Push object to candidate nodes

propagate to other pedestrians
encrypt message encrypt headers with 7DS public
key
7DS MTA
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Applications for message passing

• Email objects
• Relaying SMS messages in congested/damaged areas
• Message relaying in sensor networks
• Traffic management information relaying

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Pager as feedback channel
FLEX 1600-6400 b/s
remove from cache
SNPP (RFC 1861)
MTA
message 42 delivered
PL-900 POCSAG
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Conclussions

• 7DS as extension of infrastructure and ad-hoc
  networks
• Combine benefits of low bit-rate, but ubiquitous
  and high bit-rate, but sparse networks