Seshan Wireless Mobile

8/3/2019 Seshan Wireless Mobile

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Implications of emerging

mobile wireless network technologies on the future

Internet

Srinivasan Seshan

Computer Science DepartmentCarnegie Mellon University

(Thanks to D. Raychaudhuri and WMPG for slides/ideas)



2

Wireless is THE Key Driver for the Future

Internet

Historic shift from PC’s to mobile computing andembedded devices…

>2B cell phones vs. 500M Internet-connected PC’s in 2005

>400M cell phones with Internet capability, rising rapidly

Sensor deployment just starting, but some estimates ~5-

10B units by 2015

INTERNET

INTERNET

Wireless

EdgeNetwork

Wireless

EdgeNetwork

INTERNET

INTERNET

~500M server/PC’s, ~100M laptops/PDA’s

~750M servers/PC’s, >1B laptops, PDA’s, cell phones, sensors

20052010

Wireless

EdgeNetwork

Wireless

EdgeNetwork



3

Implications: Market Size

Past efforts emphasis on adapting wireless nodes

to support existing architecture Wireless TCP, Mobile IP, etc.

Adoption of these evolutionary changes has laggedexpectations

Market size justifies more dramatic changes

Broader architectural changes to support range of issues

created by wireless systems Consider changes to Internet that may simplify future

wireless system design



4

Trends: Growing Deployment Diversity

DevicesLaptops, PDAs, audio/videoequipment, appliances, sensorsand “Constellations” of devices

ScaleBillions of sensors & RFID tagsexpected by 2015

Deployment styles

Homes, hot-spots, airports andinfrastructure/municipal networks

Past: largely 802.11 campus networks with laptops

FUTURE

Radio technology

Sensor radios, 3+G cellular,Bluetooth, UWB, WiMax, softwareradios, and RFID



5

Trends: Growing Application Diversity

Relay Node

Access

Point

Sensor

Wired Internet

Ad-Hoc/SensorNetworks

Collision Avoidance:Car Networks

Wireless HomeMultimedia

Mesh Networks



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Implications: Diversity

New architectures must accommodate rapidlyevolving technology

Must accommodate different optimization goals

Power, coverage, capacity, price

May need to evaluate designs in heterogeneoussettings

INTERNETINTERNET

Wireless

EdgeNetwork

WirelessEdge

Network

INTERNETINTERNET

2005

2010

Wireless

EdgeNetwork

Wireless

EdgeNetwork



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Trends: Spectrum Scarcity

392551Boston

853037San Fran

767934San Diego

548683Portland

#APs Max @

1 spot

Densities of unlicenseddevices already high

Spectrum is scarcewill get worse

Improve spectrum

utilization (currently 10%)



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Implications: Spectrum Scarcity

Interference and unpredictable behavior

Need better management/diagnosis tools

Lack of isolation between deployments

Cross-domain and cross-technology

Why is my802.11 notworking?



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Implications: Spectrum Scarcity

Irrelevant to Internet architecture?

Possible changes to Internet to enable solutions Non-IP devices will play a significant role

What can the Internet do for them?

Early explorations into opportunistic use of spectrum

Explicit sharing of spectrum fair allocation

Similar to other Internet resource allocation problems Need to monitor spectrum to ensure fair-play



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Architectural Components: Addressing and

Identity

Supporting mobility in the Internet has been a

deployment failure Firewalls, reverse path filtering

Route optimization support

Alternative approach: separating identity andaddress

Several existing proposals

Support for hierarchical group identity for constellations

Support for mobility for nodes and constellations



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Architectural Components: Cross-layer

Optimization

Cross-layer optimizations have been critical in wireless

networks of the past Wireless TCP, adaptive applications, route selection

Need architectural support to simplify suchimprovements

Enable adaptation to connectivity properties/location

Configure radio to produced desired behavior athigher layers

Expose current behavior of radio link

Accommodate future link evolution



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Architectural Components: Management

and Diagnosis

Efficient, ubiquitous wireless will have to be self-managing Scale and dynamic environment

Too difficult for non-experts Simple management of “policy level” features

What steps do users have to go through to: group nodes together,enable “guest access”, ..

Must accommodate lack of traditional boundaries betweendomains

Need to measure currently hidden properties (propagationproperties, configuration of other domains, location oftransmitters, etc.) Detection of abuse important Help in diagnosis of problems



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Architectural Components: Incentives and

Economics

Enable third-party store and forwarding services

Incentives for forwarding data or providing connectivity How to billing for “roaming” access?

Mechanisms for negotiating spectrum use Incentives for sharing spectrum fairly

Securing resource (spectrum/forwarding) use Ensuring that use matches specified behavior

How to police use?



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Other Architectural Components

Location awareness Using location for addressing/identity APIs Coordinates vs. symbolic representation

Delay/disconnection tolerance Should be able to operate “infrastructure free”

Security, privacy & trust Design must address lack of isolation and infrastructure free

operation

Many others trends and architectural components… See NSF Wireless/Mobile Planning Group Workshop Report

(http://www.winlab.rutgers.edu/WMPG/)

Documents

Seshan Wireless Mobile