internet connection with wireless sensor networks l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Internet Connection with Wireless Sensor Networks PowerPoint Presentation
Download Presentation
Internet Connection with Wireless Sensor Networks

Loading in 2 Seconds...

play fullscreen
1 / 68

Internet Connection with Wireless Sensor Networks - PowerPoint PPT Presentation


  • 292 Views
  • Uploaded on

Internet Connection with Wireless Sensor Networks Lixia Zhang The Croucher Foundation Advanced Study Institute Wireless Sensor Networks December 6, 2006 Disclaimer Personal view Sharing my own experience from 25 years with TCP/IP development PHTYMH

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Internet Connection with Wireless Sensor Networks' - liam


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
internet connection with wireless sensor networks

Internet Connection with Wireless Sensor Networks

Lixia Zhang

The Croucher Foundation Advanced Study Institute

Wireless Sensor Networks

December 6, 2006

disclaimer
Disclaimer
  • Personal view
  • Sharing my own experience from 25 years with TCP/IP development
  • PHTYMH

Potentially harmful to your mental health

ASI

waves of research efforts
Waves of research efforts
  • A new direction is proposed
  • Center of research gravity shifted
  • Many efforts devoted to the new topic
  • And . . .
  • Are we pushing the frontier of science, engineering, or technology?

ASI

why talking the connection
Why talking the connection

between Internet and sensor networking ?

  • Understand what we have learned
  • How our past result may guide our future effort

ASI

what is the connection
What is the "connection" ?

Between the Internet and wireless sensor networks?

  • Sensors will be connected to the Internet!

ASI

but the most important connection
But the most important connection

The similarities between the two

  • Sensor networks: a new technology emerging on the horizon today
    • That's where the Internet was 30 years ago
    • Today's Internet: a global scale communication infrastructure
  • Sensor networking: Expected to succeed as the Internet has
    • and growing into large-scale deployment

ASI

slide8

Why multi-scale distributed sensor-networking will transform ecology

Radioastronomy

Computing

Field ecology

Supercomputers

Single Telescopes

Individual observations

… because it has done so over and over again

Very Large Array

Internet

NEON

D. Estrin, keyntote@3rd IMUA Conf

the second similarity
The second similarity
  • Both are man-built artifacts
  • A fundamental question: Have we mastered the principles for designing successful large-scale distributed systems?
  • Where to find these principles?

ASI

here s what a famous scientist had to say
Here's what a famous scientist had to say
  • "The principle of science, the definition, almost, is the following: the test of all knowledge is experiment. Experiment is the sole judge of scientific 'truth'. "

ASI

slide11
"But what is the source of knowledge? Where do the laws that are to be tested come from?
  • Experiment, itself, helps to produce these laws, in the sense that it gives us hints."

ASI

the best way to find learn the design principles
The best way to find/learn the design principles
  • Is to build a sensor network
    • then one can learn from the successes, and more importantly from the lessons
  • We do not have to start from a blank sheet of paper
    • The Internet: real-world example of the largest system human ever built
    • Learn from a critical examination of the successes and lessons of the Internet

ASI

a walk through history

Programs

H/W-/W Platforms

/Publications

LWIM Paper (ACM ISLPED)

DARPA DSN

Under-sea Networks

Ubiquitous Computing

Distributed Tracking

Robotic Ecology (DARPA ISAT 1999)

DARPA LWIM

LWIM-III

(UCLA)

SmartDust, Diffusion (MobiCom 1999)

DARPA AWAIRS

TinyOS (OSDI 2000)

WINS(UCLA/ROckwell)

Embedded Everywhere (NRC Report 2001)

DARPA SensIT

MICA(Berkeley)

ACM SenSys and ACM/IEEE IPSN

DARPA PACC

MICA2(Berkeley/Crossbow)

NSF CENS STC

ACM TOSN

DARPA NEST

NSF CASA ERC

HelioMote

Telos

NSF NeTS-NOSS

Cyclops

NSF Cyber Physical Systems?

Illumimote

LEAP

A Walk Through History

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

D. Estrin, keyntote@3rd IMUA Conf

brief history of the internet
Brief History of the Internet
  • 1968 - DARPA (Defense Advanced Research Projects Agency) contracts with BBN (Bolt, Beranek & Newman) to create ARPAnet
  • 1970 - First five nodes:
    • UCLA
    • Stanford
    • UC Santa Barbara
    • U of Utah, and
    • BBN
  • 1974 - TCP specification by Vint Cerf
  • 1984 – On January 1, the Internet with its 1000 hosts converts en masse to using TCP/IP for its messaging

from William F. Slater, III

Chicago Chapter of the Internet Society

ASI

aren t there big enough differences
aren't there big enough differences

Between Internet and sensor networking

    • That would make the Internet experience irrelevant?

e.g.

  • Wireless bandwidth is intrinsically limited
    • But see the progress in WiFi speed over the last few years
  • "a fundamental challenge in wireless sensors is the energy problem"

ASI

the fundamental challenge
The fundamental challenge
  • Lies on discovering the principles for large scale systems
    • Technologies can, and will, be moving forward to meet whatever the market needs

ASI

network design in practice
Network Design in Practice
  • The initial packet switchted network design and validation were done while the system was small
  • Focus: solving the functional problems to get the system up and running
    • TCP/IP: delivering packets across networks made of different networking technologies
  • Early experiments necessarily done in a small setting that can be understood and controlled
    • ARPAnet started with a few nodes, then grew to dozens of nodes.

ASI

scalability consideration
Scalability Consideration

during the design phase:

  • Designs explicitly assumes that the network would grow large
    • Larger number of nodes getting connected
    • Larger number of route table entries;
    • Larger volume of data traffic
    • More types of new applications
      • And with different performance requirements

ASI

internet scaling up
Internet scaling up
  • A success design in enabling growth to large-scale.
  • The Internet now faces new challenges resulted from its growth
    • Many new (unforeseen) problems popped up from practice
    • Many open challenges
  • Take a look at a real large scale distributed network

ASI

the internet as a large system
The Internet as a Large System
  • Expected impact of larger size
    • More users
    • Larger traffic volume
    • Bigger routing tables
    • Wider range of heterogeneity in networking technology

the Internet has grown both in size and in importance

ASI

1 growing large includes changes in user community
1. Growing Large Includes:Changes in User Community
  • Small-scale: a close-nit, friendly research community
  • Large-scale open system: facing brutal real world
    • Expected user population growth
    • Unexpected changes in types of users: diverse interest
      • Millions of users contribute and gain from the Internet
      • Spammers, phishing, DDoS

ASI

could sensors possibly be abused
could sensors possibly be abused?
  • In day-1 of Internet, no one thought it could possibly be abused either
  • What bad things can be done to sensor networking?
    • Military applications?
    • Terrorists?
  • Bottom line: When sensor networks start providing valuable services to some people, there will be some others who have a different interest

ASI

2 growing large includes changes in operational community

Small, knowledgeable, close-knit research community

2. Growing Large Includes:Changes in Operational Community
  • Small-scale: knowledgeable operators committed to growth and promotion of system
    • Collaboration toward the common goal.
  • Large-scale: diverse operators with competing agendas
    • Highly diverse levels of expertise
    • Competition instead of collaboration

Large operator community with different degrees of expertise

ASI

operational errors an example
Operational Errors: an example
  • Operational errors have been the cause of most major outages so far
  • One common configuration error: route leak-out

Global Internet

regional ISP

ASI

a few route leak out cases
A few route leak-out cases
  • Apr. 25, 1997 At 11:30 am EST, a router in AS7007 accidentally advertised to its peers 73,000+ routes. A large number of networks became unreachable as a result. This incident was partly aggravated by some BGP implementations’ inability to remove the false routes; even after AS7007 disconnected their router, the false routes still persisted for at least seven hours
  • Apr. 7, 1998 AS8584 announced over 11,000 prefixes belonging to other networks ……
  • Apr. 7, 1999 AS7374 leaked many routes via the Internet exchange point CIX (AS1280). It appears to be announcing routes for most of the Internet ...
  • Apr. 6, 2001 Cable and Wireless (AS3561) had a configuration error that caused it to propagate route announcements from a downstream customer AS15412….
  • ........
  • December 2004 AS9121 announced routes to almost all the Internet destinations, successfully hijacked a large number of prefixes hosted by tier-1 ISPs such as ATT and UUNET

ASI

persistent existence
Persistent existence

"Understanding BGP Misconfiguration", SIGCOMM 2002

ASI

another example dns misconfiguration

foo.com. NS ns1.foo.com.

foo.com. NS ns2.foo.com.

foo.com. NS ns3.foo.com.

ns1.foo.com. A 1.1.1.1

ns2.foo.com. A 2.2.2.2

ns3.foo.com. A 3.3.3.3

foo.com. NS ns1.foo.com.

foo.com. NS ns2.foo.com.

foo.com. NS ns3.foo.com.

ns1.foo.com. A 1.1.1.1

ns2.foo.com. A 2.2.2.2

ns3.foo.com. A 3.3.3.3

Another example: DNS misconfiguration

DNS stores all data in Resource Records (RR)

  • NS Resource Record:
    • Provides the names of a zone’s authoritative servers
    • Stored both at the parent and at the child zone

com

  • A Resource Record
    • Associated with a NS resource record
    • Stored at the parent zone (glue A record)

foo.com

ASI

common config error lame delegation
Common config. error: Lame Delegation

foo.com. NS A.foo.com.

foo.com. NS B.foo.com.

A.foo.com. A 1.1.1.1

B.foo.com. A 2.2.2.2

com

1) Non-existing server

foo

2) Non-authoritative

3) Useless referral

A.foo.com

B.foo.com

ASI

major incidents due to config errors

Internet

Microsoft DNS servers

Major incidents due to config. errors

“Microsoft's websites were offline for up to 23 hours -- the most dramatic snafu to date on the Internet --because of an equipment misconfiguration”

-- Wired News, Jan 2001

ASI

3 growing large includes unforeseen protocol impl consequence
3. Growing Large Includes: unforeseen protocol impl. consequence
  • We are not talking about implementation bugs here
    • Though it is a serious problem
      • i.e. all the viruses/worms resulted from exploitation of bugs (in either OS or applications)
  • The problem: protocol implementors do not understand the consequence of specific protocol implementation decisions

ASI

benign implementation security threat
Benign implementation  security threat
  • In spring'03 U. Wisc experienced sudden increase in incoming traffic: potential DDoS?
  • Notified the ISP and blocked the attack traffic
  • The traffic did not stopped

ASI

what happened
What happened?
  • Several popular Netgear products "relied on a separate NTP-based time source to set the current date and time, as it did not have an internal battery and clock. The product is hard-coded with specific NTP time sources that are accessible through the public Internet."
  • "The Candidate Firewall Product met all the criteria elements in the Baseline and Residential modules and therefore has attained ICSA Labs Firewall Certification."

These home routers: send 1 NTP query per second!

ASI

4 growing large includes unforeseen protocol design consequence

ISP

4. Growing Large Includes: unforeseen protocol design consequence
  • In designing a protocol: exactly what information should/not be carried in the protocol message?
  • One common view: the more the better
  • One design case: BGP aggregator attribute

1.2.3.0/24

Aggr=R1

R3

R1

1.2.3.0/25

R2

1.2.3.128/25

ASI

subtle design issues show up at worst time

AS Path= <568>,AG=R1

AS Path= <209, 268>, R1

AS Path= <568>,AG=R2

AS Path= <209,568>, R2

subtle design issues show up at worst time
  • R1 and R2 connect to the upstream ISP.
  • AS X: local decision to prefer R1 or R2 as entry point.
    • AGG value differs depending on choice of R1 or R2.
  • During a worm attack: wild route fluctuationglobal flood of updates

AS209

R1

R2

We are here

Local instability  global overhead

ASI

5 growing large includes unforeseen component behaviors
5. Growing Large Includes: unforeseen component behaviors
  • Routing protocols are designed with quick reactions to all topological changes
  • Unforeseen: started seeing small number of unstable edge networks
    • Inevitable in large scale
  • Global impact

C

Internet

D

A

B

X

Y

E

ASI

let s fix it bgp damping design
Let's fix it: BGP Damping Design
  • Use penalty to track route instability
    • Increase upon receiving an update
    • Otherwise decay exponentially
  • Suppress the route if penalty is over the cutoff threshold
  • Reuse when the penalty drops below the reuse threshold

ASI

expected bgp damping behavior
Expected BGP Damping Behavior

C

Internet

D

damped

A

B

X

Y

E

C

Internet

D

A

B

X

Y

E

ASI

route flap damping exacerbates internet routing convergence
"Route Flap Damping Exacerbates Internet Routing Convergence"
  • "We analyze a previously not well-studied interaction between BGP's route withdrawal process and its route flap damping mechanism for ensuring the overall stability of the Internet routing system.
  • "This interaction can, depending upon the topology, suppress up to one hour the propagation of a route that has been withdrawn once and re-announced."

ASI

6 growing large includes unforeseen dynamics in large scale

C

Internet

D

A

BA

XBA

A

B

another flap!

X

Y

E

6. Growing Large Includes: unforeseen dynamics in large scale

C

Internet

XCBA

D

XDBA

W

XEBA

W

XDCBA …

W

A

B

damped!

X

Y

E

ASI

secondary charge
Secondary Charge

Path exploration

Secondary charging

ASI

7 growing large includes growth in value and importance
7. Growing Large Includes:Growth in value and importance!
  • Value and importance of the Internet attract malicious attacks
  • There exists an underground economy that is driving all the bad traffic in the Internet today
    • Using our network, our technology to attack us
  • This was not expected
    • Thus the original Internet protocol design and implementation were vulnerable in face of these attacks

ASI

8 growing large includes trust exploited by attackers

www.google.com ?

Answer:

www.google.com A 4.4.4.10

Authority:

google.com NS ns.google.com

Additional:

ns.google.com A 4.4.4.1

www.google.com

= 4.4.4.10

8. Growing Large Includes:Trust Exploited By Attackers

Original DNS design:

information piggybacking  performance improvement

Google DNS server

UCLA Caching Server

Query www.google.com

UCLA Laptop

ASI

dns cache poisoning by attracting servers to bad place

www.google.com

= 128.9.128.127

Query www.google.com

DNS cache poisoning byattracting servers to bad place

Response www.attacker.com A 128.9.128.127

attacker.com NS ns.attacker.com

attacker.com NS www.google.com

ns.attacker.com A 128.9.128.2

www.google.com A 128.9.128.127

UCLA Caching Server

attacker.com DNS server

Query www.attacker.com

UCLA Laptop

Remote attacker

ASI

dns cache poisoning by exploiting weakness in protocol design

www.google.com ?

answer

Answer:

www.google.com A 128.9.128.127

Authority:

google.com NS ns.google.com

Additional:

ns.google.com A 128.9.128.2

www.google.com

= 128.9.128.127

www.google.com?

Query www.google.com

DNS cache poisoning by Exploiting weakness in protocol design

google.com NS ns.google.com

ns.google.com A 4.4.4.1

128.9.128.2

www.google.com A 128.9.128.127

Google DNS server

UCLA Caching Server

UCLA Laptop

ASI

putting the problems in context
Putting the Problems in Context
  • The above is only a small sample set of observed problems due to growing large
  • The original protocol design/implementation enabled Internet growth to large scale, but are not well suited to maintain it at large scale

ASI

internet protocol design starting small
Internet protocol design: starting Small
  • Aim at the minimal set of bits necessary for data delivery
  • Explicitly enumerates all possible physical failures
    • Node failure: fail stop
    • Link failure: disconnect
    • Data delivery failure: bit error, our of order, loss, duplicates
  • Implicitly assumes that
    • Every component follows the rules
    • No faults other than physical failures listed above
  • Reality taught us: other types of faults lead to failures

ASI

on being the right size
"On Being the Right Size"
  • “Let us take the most obvious of possible cases, and consider a giant man sixty feet high ... These monsters were not only ten times as high as Christian, but ten times as wide and ten times as thick, so that their total weight was a thousand times his ... Unfortunately the cross sections of their bones were only a hundred times those of Christian, so that every square inch of giant bone had to support ten times the weight borne by a square inch of human bone.”

“For every type of animal there is a most convenient size, and a large change in size inevitably carries with it a change of form.”

ASI

broader lessons of large scale
Broader Lessons of Large Scale
  • Large-Scale deployment of sensor networks (millions of motes) envisioned
  • Sensor networks:
    • The initial deployment is necessarily small in scale
      • Thus will not expose those problems that can only surface when the system grows large
    • once the size grows large enough,
      • Will include some faulty components
      • Will see a move from a few expert operators to the broad public (with diverse expertise)
      • Will experience unexpected interactions
      • Will attract attacks if system is successful
  • Are these issues adequately considered in the current design efforts?

ASI

sensys 2005 program
Sensys 2005 Program
  • Sensornet Services
    • Radio Interferometric Geolocation
    • High-Accuracy, Low-Cost Localization System for Wireless Sensor Network
    • A New Approach for Establishing Pairwise Keys for Securing Wireless Sensor Networks
    • TSAR: A Two Tier Sensor Storage Architecture Using Interval Skip Graphs
  • Deployment Experience
    • A Macroscope in the Redwoods
    • Design and Deployment of Industrial Sensor Networks: Experiences from the North Sea and a Semiconductor Plant
  • Networking
    • A Unifying Link Abstraction for Wireless Sensor Networks
    • Z-MAC: A hybrid MAC for wireless sensor networks
    • Packet Combining in Sensor Networks
    • Siphon: Overload Traffic Management using Multi-Radio Virtual Sinks
  • Synchronization
    • Estimating Clock Uncertainty for Efficient Duty-Cycling in Sensor Networks
    • Firefly-Inspired Sensor Network Synchronicity with Realistic Radio Effects
  • Applications
  • Design Frameworks
    • Lightweight Detection and Classification for Wireless Sensor Networks in Realistic Environments
    • Intelligent Light Control using Sensor Networks
  • Software support
    • Algorithms for Generic Role Assignment in Wireless Sensor Networks
    • VM*: A Scalable Runtime Environment for Sensor Networks
    • Sympathy for the Sensor Network Debugger

ASI

sensys 2005 posters
Sensys 2005 Posters
  • Exploiting Multi-Channel Diversity to Speed Up Over-the-Air Programming of Wireless Sensor Networks
  • Bayesian Localization in Wireless Networks Using Angle of Arriva
  • Impact of Intentional Mobility in Sparse Sensor Networks
  • CONCERT: aggregation-based CONgestion Control for sEnsoR neTworks
  • Accuracy-aware Data Modeling in Sensor Networks
  • Secure Dissemination of Code Updates in Sensor Networks
  • Splitting The Sensor Node
  • A Sensor Network Based Landslide Prediction System
  • Sensor Networks for Landslide Detection
  • Robot Couriers: Precise Mobility in a Wireless Network Testbed
  • A Dynamic En-route Scheme for Filtering False Data Injection in Wireless Sensor
  • A New Scheme on Link Quality Prediction and its Applications to Metric-Based Routing
  • Automatic Programming with Semantic Streams
  • Stop the Clock! New Directions for Embedded Controllers in Wireless Sensor Networks

ASI

sensys 2006 session topics
Sensys 2006: session topics
  • Operating Systems
  • Sensing
  • Routing and Dissemination
  • Configuration
  • In-network Processing
  • Radio Propagation and Transport
  • Storage and Abstractions
  • Architecture
    • CarTel: A Distributed Mobile Sensor Computing System
    • MELETE: Supporting Concurrent Applications in Wireless Sensor Networks
    • The Tenet Architecture for Tiered Sensor Networks
  • Media Access Control

ASI

implications for new designs
Implications For New Designs
  • The Fundamental Design Problem is Scale
    • Internet Problems Will Recur in Overlays, Sensor networks, separate control planes, etc.
    • Difficult to test on smaller scales, but will be facts once the size grows large enough
  • Expected Results of any successful system
    • Will include some faulty components
    • Will see a move from a few expert operators to the broad public (with diverse expertise)
    • Will experience unexpected interactions
    • Will attract attacks if system becomes valuable

ASI

security and resiliency
Security and Resiliency
  • Resiliency: resistant to known and unknown faults
  • Security: definition?
    • Cryptographic-based protection?
      • E.g. secrecy, authentication, non-repudiation
  • A thought exercise:
    • Which of the above mentioned problems can be eliminated by crypto?
    • Which of them can be eliminated without using crypto?

ASI

challenges in designing for large scale
Challenges in designing for large scale
  • Systems grow into large-scale along multiple dimensions
    • The size is perhaps the easiest part to handle
  • Most problems do not occur till the system grows large
  • Large-Scale Systems Difficult to Model
    • Testbeds don’t achieve desired scale, lack complex input factors
    • Simulations do not have the ingredients in real large scale setting

ASI

resiliency and the internet
Resiliency and the Internet
  • Internet has taught us a rich set of lessons
    • Have we collected them all?
  • Internet can serve as primary experimental lab
    • Exhibits real problems of large-scale
    • Use it as a lab to identify challenges and test concepts

ASI

slide63
The principle of science, the definition, almost, is the following: the test of all knowledge is experiment. Experiment is the sole judge of scientific "truth".

ASI

slide64
But what is the source of knowledge?
  • Where do the laws that are to be tested come from?
  • Experiment, itself, helps to produce these laws, in the sense that it gives us hints.

ASI

slide65
But also needed is imagination to create from these hints the great generalizations — to guess at the wonderful, simple, but very strange patterns beneath them all, and then to experiment to check again whether we have made the right guess.

ASI

what to carry away
What to carry away
  • Internet proved that we know how to make a small system successful
  • If successful  growing large
  • Lessons: Scalability is a multi-dimension challenge
    • When growing large: new problems show up
    • Being able to grow large ≠being able to sustain at large

ASI

what to carry away67
What to carry away
  • Need a vision to forecast technology advances and their potential impact on the growth of the system to be designed
  • Research challenge: mastering the principles for designing large-scale systems
    • Internet serves as a great lecture hall
    • Prinicples and lessons learned should be applicable to other types of large scale deployment

ASI

lixia@cs ucla edu

Thank you!

Questions?

lixia@cs.ucla.edu

ASI