Ad Hoc Networking via Named Data

Michael Meisel, Vasileios Pappas, and Lixia ZhangUCLA, IBM Research

MobiArch’10, September 24, 2010

2011. 3. 13Shinhaeng Oh

(shoh@mmlab.snu.ac.kr)

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CONTENTS• Background

– Internet Protocol vs. Named Data• Existing Solutions for mobile networks

– Ad-Hoc Networking over IP– Limitation of IP-Routing

• New Direction for mobile networks– NDN for Ad-Hoc Networking– Design Example : LFBL

• Conclusion

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Introduction• TCP/IP and CCN Protocol Stacks

– Replace packets with Data Objects or Interests– Replace Addresses with Names of Objects

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Ad-Hoc Networking over IP

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201.239.0.101

212.123.3.214198.102.182.104

162.201.193.210

1. Each node is assigned an IP address

112.191.203.117

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Ad-Hoc Networking over IP

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201.239.0.101

212.123.3.214198.102.182.104

162.201.193.210

2. Applications communicate by sending data to specific destination addresses

112.191.203.117

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Ad-Hoc Networking over IP

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201.239.0.101

212.123.3.214198.102.182.104

162.201.193.210

Sending data

3. When node move, determine a single best path to the given destination IP, and delivers data

112.191.203.117

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Limitations of the IP-Routing (1)• Difficult to assign IP addresses (moving nodes)

– IP addresses management is tightly controlled– It requires infrastructure support (e.g. DHCP)Þ ad-hoc networks need infrastructure-free !!

• In mobile, IP address is less meaningful– Wired networks, IP represent topology location– But, ad-hoc network do not have fixed location– Temporary unique identifier for device is needed

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NDN for Ad-Hoc Networking (1)• Assign IP address to each nodes --No longer needs

– To forward interests & data packets,– Nodes can use application data names directly

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interest interest

forward or broad-cast

Limitations of the IP-Routing (2)• Data is invisible in today’s IP-centric architecture

source destination– It’s sub-optimal delivery

• Accuracy of routing state maintained at each nodeOverhead to keep this state consistent --tradeoff– High node mobility– Constant movement in the aggregate at a large network

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NDN for Ad-Hoc Networking (2)• Caching (traditional approach)

– Ideally, each cached object has to be retrieved in its en-tirety from the same caching node.

– But, images & audios & videos cannot fit within one packet– Transparent caching techniques work only in static network

• Caching (NDN)– Intermediate node can forward to request node any part of

file

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subsequentrequest

chunk

Limitations of the IP-Routing (3)• Receivers are in a better position to make forward

decision than senders– In broadcast channel, nodes can hear the transmission– To keep all neighbors’ movement and connectivity changes

will increase the routing table update overhead

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NDN for Ad-Hoc Networking (3)• Interest packets can be forwarded multiple path

– More than one direction returns the request data– A node can evaluate which path gives the best perfor-

mance– Send future Interest for same data source in that direction– Remove critical dependency on pre-computed single paths

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Design Example: LFBL• LFBL: Listen First, Broadcast Later• Uses a variation of NDN’s 3-way exchange

– Name prefix announcements– Interest forwarding– Data return

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REQUESTName of application

dataRe-

sponse

Re-sponse

Design Example: LFBL• LFBL: Listen First, Broadcast Later• Uses a variation of NDN’s 3-way exchange

– Name prefix announcements– Interest forwarding– Data return

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ACK Destina-tion

Design Example: LFBL• LFBL: Listen First, Broadcast Later• Uses a variation of NDN’s 3-way exchange

– Name prefix announcements– Interest forwarding– Data return

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ACK Destina-tion

1

2

Design Example: LFBL• LFBL: Listen First, Broadcast Later• Uses a variation of NDN’s 3-way exchange

– Name prefix announcements– Interest forwarding– Data return

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ACK Destina-tion

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Design Example: LFBL• LFBL: Listen First, Broadcast Later• Uses a variation of NDN’s 3-way exchange

– Name prefix announcements– Interest forwarding– Data return

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ACK Destina-tion

Design Example: LFBL• LFBL: Listen First, Broadcast Later• Uses a variation of NDN’s 3-way exchange

– Name prefix announcements– Interest forwarding– Data return

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ACK Destina-tion

1

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Design Example: LFBL• LFBL: Listen First, Broadcast Later• Uses a variation of NDN’s 3-way exchange

– Name prefix announcements– Interest forwarding– Data return

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ACK Destina-tion

Performance Evaluation• Implemented LFBL in QualNet network simulator

– Effect of % of mobile nodes– Move at a fixed rate of 30m/s (random waypoint mobility)

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Conclusion• Frequent changes in topology had a direct impact

on the performance of current protocols• Designed a new forwarding protocol: LBFL

– For highly dynamic multi-hop wireless networks– Distributed forwarding capability with essentially no routing

protocol• Through named data networking approach,

– We can sketched out promising architectural direction to de-velop effective and efficient solution for ad-hoc networks

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QnA

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Related Work: DSDV, AODV• Destination-Sequenced Distance-Vector Routing

(DSDV) is a table-driven routing scheme for ad hoc mobile networks based on Bellman-Ford algorithm– Each entry in the routing table contains a sequence num-

ber, they generally even if a link is present, odd used• For example the routing table of Node A in Network

Destina-tion

Next Hop # of Hops Seq. num-ber

Install Time

A A 0 A 46 001000B B 1 B 36 001200C B 2 C 28 001500