delay tolerant networks roland cheng. april 24, 2007mobile communication2 pan ~1m lan ~100 m man ~10...
Post on 20-Dec-2015
216 views
TRANSCRIPT
![Page 1: Delay Tolerant Networks Roland Cheng. April 24, 2007Mobile Communication2 PAN ~1m LAN ~100 m MAN ~10 km WAN ~1,000 km Internet ~10,000 km Inter-planetary](https://reader030.vdocuments.site/reader030/viewer/2022032800/56649d415503460f94a1b2d8/html5/thumbnails/1.jpg)
Delay Tolerant Networks
Roland Cheng
![Page 2: Delay Tolerant Networks Roland Cheng. April 24, 2007Mobile Communication2 PAN ~1m LAN ~100 m MAN ~10 km WAN ~1,000 km Internet ~10,000 km Inter-planetary](https://reader030.vdocuments.site/reader030/viewer/2022032800/56649d415503460f94a1b2d8/html5/thumbnails/2.jpg)
April 24, 2007 Mobile Communication 2
PAN ~1m
LAN ~100 m
MAN ~10 km
WAN ~1,000 km
Internet ~10,000 km
Inter-planetary Communication ~100×106 km
![Page 3: Delay Tolerant Networks Roland Cheng. April 24, 2007Mobile Communication2 PAN ~1m LAN ~100 m MAN ~10 km WAN ~1,000 km Internet ~10,000 km Inter-planetary](https://reader030.vdocuments.site/reader030/viewer/2022032800/56649d415503460f94a1b2d8/html5/thumbnails/3.jpg)
April 24, 2007 Mobile Communication 3
Outline
Review Internet protocol stack
• Internet vs. Delay Tolerant Networks
• Lagrange point relays
• Summary
![Page 4: Delay Tolerant Networks Roland Cheng. April 24, 2007Mobile Communication2 PAN ~1m LAN ~100 m MAN ~10 km WAN ~1,000 km Internet ~10,000 km Inter-planetary](https://reader030.vdocuments.site/reader030/viewer/2022032800/56649d415503460f94a1b2d8/html5/thumbnails/4.jpg)
April 24, 2007 Mobile Communication 4
5 Layer TCP/IP Model
Application Layer http, ssh, pop3
Transport Layer TCP, UDP
Network Layer IP
Data Link Layer 802.11
Physical Layer MPSK, MQAM
![Page 5: Delay Tolerant Networks Roland Cheng. April 24, 2007Mobile Communication2 PAN ~1m LAN ~100 m MAN ~10 km WAN ~1,000 km Internet ~10,000 km Inter-planetary](https://reader030.vdocuments.site/reader030/viewer/2022032800/56649d415503460f94a1b2d8/html5/thumbnails/5.jpg)
April 24, 2007 Mobile Communication 5
Outline
• Review Internet protocol stackInternet vs. Delay Tolerant Networks
• Lagrange point relays
• Summary
![Page 6: Delay Tolerant Networks Roland Cheng. April 24, 2007Mobile Communication2 PAN ~1m LAN ~100 m MAN ~10 km WAN ~1,000 km Internet ~10,000 km Inter-planetary](https://reader030.vdocuments.site/reader030/viewer/2022032800/56649d415503460f94a1b2d8/html5/thumbnails/6.jpg)
April 24, 2007 Mobile Communication 6
Assumptions in TCP/IP
• Small propagation latencies
• High data rates
• Bidirectional, symmetric channels
• Continuous connectivity
A B
![Page 7: Delay Tolerant Networks Roland Cheng. April 24, 2007Mobile Communication2 PAN ~1m LAN ~100 m MAN ~10 km WAN ~1,000 km Internet ~10,000 km Inter-planetary](https://reader030.vdocuments.site/reader030/viewer/2022032800/56649d415503460f94a1b2d8/html5/thumbnails/7.jpg)
April 24, 2007 Mobile Communication 7
Assumptions in DTN
• Large propagation delays
• Low data rates
• Asymmetric channels
• Intermittent connectivity
![Page 8: Delay Tolerant Networks Roland Cheng. April 24, 2007Mobile Communication2 PAN ~1m LAN ~100 m MAN ~10 km WAN ~1,000 km Internet ~10,000 km Inter-planetary](https://reader030.vdocuments.site/reader030/viewer/2022032800/56649d415503460f94a1b2d8/html5/thumbnails/8.jpg)
April 24, 2007 Mobile Communication 8
Bundling Protocol
• Place another layer between application and transport layer
• Bundling protocol (CFDP)– Keeps all data and meta data needed to transmit a
packet until receive ACK (store-and -forwarding)– Transmits data optimistically– Routing of packets should take advantage of
scheduled outage– Uses new ARQ algorithms that can handle long
delays
![Page 9: Delay Tolerant Networks Roland Cheng. April 24, 2007Mobile Communication2 PAN ~1m LAN ~100 m MAN ~10 km WAN ~1,000 km Internet ~10,000 km Inter-planetary](https://reader030.vdocuments.site/reader030/viewer/2022032800/56649d415503460f94a1b2d8/html5/thumbnails/9.jpg)
April 24, 2007 Mobile Communication 9
Data Flow Example in DTN
![Page 10: Delay Tolerant Networks Roland Cheng. April 24, 2007Mobile Communication2 PAN ~1m LAN ~100 m MAN ~10 km WAN ~1,000 km Internet ~10,000 km Inter-planetary](https://reader030.vdocuments.site/reader030/viewer/2022032800/56649d415503460f94a1b2d8/html5/thumbnails/10.jpg)
April 24, 2007 Mobile Communication 10
Outline
• Review Internet protocol stack
• Internet vs. Delay Tolerant NetworksLagrange point relays
• Summary
![Page 11: Delay Tolerant Networks Roland Cheng. April 24, 2007Mobile Communication2 PAN ~1m LAN ~100 m MAN ~10 km WAN ~1,000 km Internet ~10,000 km Inter-planetary](https://reader030.vdocuments.site/reader030/viewer/2022032800/56649d415503460f94a1b2d8/html5/thumbnails/11.jpg)
April 24, 2007 Mobile Communication 11
Lagrange Point Relays
Sun Earth
![Page 12: Delay Tolerant Networks Roland Cheng. April 24, 2007Mobile Communication2 PAN ~1m LAN ~100 m MAN ~10 km WAN ~1,000 km Internet ~10,000 km Inter-planetary](https://reader030.vdocuments.site/reader030/viewer/2022032800/56649d415503460f94a1b2d8/html5/thumbnails/12.jpg)
April 24, 2007 Mobile Communication 12
Lagrange Point Relays
• A Lagrange point is a solution to the restricted 3-body problem– a small object at a Lagrange point will remain
stationary relative to two large, orbiting masses, assuming only gravitational effects
• Placing a relay station at L4 and L5 will provide alternative signal paths when no line-of-sight
![Page 13: Delay Tolerant Networks Roland Cheng. April 24, 2007Mobile Communication2 PAN ~1m LAN ~100 m MAN ~10 km WAN ~1,000 km Internet ~10,000 km Inter-planetary](https://reader030.vdocuments.site/reader030/viewer/2022032800/56649d415503460f94a1b2d8/html5/thumbnails/13.jpg)
April 24, 2007 Mobile Communication 13
Outline
• Review Internet protocol stack
• Internet vs. Delay Tolerant Networks
• Lagrange point relaysSummary
![Page 14: Delay Tolerant Networks Roland Cheng. April 24, 2007Mobile Communication2 PAN ~1m LAN ~100 m MAN ~10 km WAN ~1,000 km Internet ~10,000 km Inter-planetary](https://reader030.vdocuments.site/reader030/viewer/2022032800/56649d415503460f94a1b2d8/html5/thumbnails/14.jpg)
April 24, 2007 Mobile Communication 14
Summary
• TCP/IP is not suitable for interplanetary communication– Large propagation delays, intermittent
connectivity
• Bundling protocol extends the network stack by providing asynchronous store-and-forwarding service
• Lagrange point relays can alleviate LOS occlusions