Scheduling Routing in InterPlaNetary Internet

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Scheduling Routing in InterPlaNetary Internet

• M.A. Bonuccelli F. Martelli S. Pelagatti

bonucce,susanna_at_di.unipi.it, f.martelli_at_isti.cnr
.it
June 9-10, 2004
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Outline

• Motivations
• The problem
• Literature
• Our results
• Work in progress

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InterPlaNetary Internet
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PlaNetary Network architecture
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Satellites

• SS/TDMA coverage area is divided in macrocell
• N macrocell ?
• N frequencies ?
• N transponders
• RF switch on board of satellite

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Satellite Constellations

• Typically toroidal meshes

Teledesic
Iridium
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The Problem

• Scheduling packets on switch
• avoiding collisions on I/O ports
• minimizing total delivery time
• maximizing number of messages delivered
• Routing packets within constellation
• choosing among shortest paths
• load balancing among alternative routes

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Literature

• Results on single satellite systems
• BCW81 - Bongiovanni Coppersmith and Wong. An
  optimal Time Slot assignment algorithm for a
  SS/TDMA system with variable number of
  tarsponders. IEEE Transactions on Communication,
  37721-726, 1981
• BGW91 Bonuccelli Gopal and Wong. Incremental
  Time Slot Assignement in SS/TDMA satellite
  systems. IEEE Transactions on Communication,
  391147-1156. 1991.
• .. many others

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Literature (contd.)

• Results on constellations
• Inukai81 Inukai. SS/TDMA networking via ISL. In
  ICC81, pp. 70.6.1--70.6.5, 1981
• BBB87 Bertossi Bongiovanni Bonuccelli. Time
  Slot Assignment in SS/TDMA systems with
  intersatellite links. IEEE Transactions on
  Communication, 35602-608. 1987.
• GG92 Ganz Gao. Efficient Algorithms for SS/TDMA
  scheduling. IEEE Transactions on Communication,
  381367-1374. 1992

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Our results on Single satellites

• Online algorithms (BP00)
• Competitive ratio worst case
• Average close to 1 on simulations on different
  traffic scenarios
• QoS scheduling for Hard Real Time (BC01)
• EDF and Rate Monotonic
• Performance guarantees

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Results on Constellations

• Two models investigated
• link centred
• NP completeness (from BBB87)
• Optimal Algorithm for trees (BMP04a)
• switch centred
• Optimal Algorithm with load balancing (BMP04b)

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Work in progress

• QoS scheduling SRT/HRT on constellations
• offline
• online
• Performance guarantees
• Multimedia traffic Jitter
• www.pc-bonucce.di.unipi.it/WMGroup/

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References

• (BP00) Bonuccelli Pelagatti. Optimal On demand
  Packet Scheduling in single-hop multichannel
  communication systems. IEEE IPDPS 2000, vol. 1 p.
  343-352. 2000.
• (BC01)Bonuccelli Clò. Scheduling of Real Time
  messages in optical broadcast-and-select
  networks. IEEE/ACM Transactions on Networking,
  9(5)541-552, 2001.
• (BMP04a) Bonuccelli Martelli Pelagatti. Optimal
  Packet Scheduling in Tree Structured LEO
  satellite clusters. MONET, to appear.
• (BMP04b)Bonuccelli Martelli Pelagatti. Optimal
  Packet scheduling and load balancing algorithms
  for LEO/MEO satellite Networks. TR Dip
  Informatica Pisa, submitted for publication.