Internet Trends and the Cost of Connectivity

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Internet Trends and the Cost of Connectivity

• 1st BroadSky Workshop, Lacco Ameno, Italy
• November 6, 2003
• Will Ivancic wivancic_at_grc.nasa.gov

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NASA Glenns Space Communications Program

• Experimental Satellites (70s early 90s)
• Maintain US preeminence in satellite
  communication
• Focused on Commercial Communications Satellites
• Space Communications (mid 90s )
• NASA Mission Focused
• Earth Science
• Computer Information and Communications
  Technology (CICT)
• Human Exploration and Development of Space
• Aeronautics (2000 )
• Capacity (Air Traffic Management)
• Safety (Weather and Security)

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Aeronautics

• Communications, Navigation, and Surveillance (Low
  Data-Rate Requirements)
• Delivery via VHF and/or Satellite
• Command and Control requires a reliable transport
  protocol
• Current protocols
• Aircraft Communications Addressing and Reporting
  System (ACARS)
• Aeronautical Telecommunication Network (ATN)
• Moving Toward IPv6 (commercial standards)
• Weather (Low Data-Rate Requirements)
• Possible use of multicasting and broadcasting
  protocols
• Low Bandwidth requirements
• May use non-reliable transport protocols (no
  feedback)
• Others (Medium to High Data-Rate Requirements)
• Entertainment
• Maintenance
• Video Surveillance
• Black Box Data
• eBusiness (Records, manuals, maps, etc)

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Transmission Control Protocol (TCP)

• Currently the Dominant Reliable Transport
  Protocol in the Internet
• Designed to be fair and operate over shared
  infrastructure (Congestion Dominates most
  end-to-end links)
• Slow Start (Exponential Increase) to probe for
  bandwidth
• Rate Halving when packet is lost (Multiplicative
  Decrease)
• Rate Increase by 1 packet per round trip
  (Additive Increase)
• Parameters Affecting Throughput
• Bandwidth-Delay Product
• Congestion
• Errors
• File Size

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Round Trip Time (RTT) Delay

• US to Japan Terrestrial
• 20 100 msec
• GEO Satellite
• 550 msec (Theory)
• Real Systems 0.8 - 1.5 sec
• 802.11 Wireless Ethernet
• Negligible (Network Delay Dominates)
• G2 / G3 Cellular
• 1 Second using General Packet Radio Services
  (GPRS) from T-Mobile
• LEO
• 1 2.5 Seconds (Using Globalstar)

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Performance Enhancing Proxies (PEPs)

• Middleware deployed to help TCP performance over
  links with large bandwidth-delay products
• Attempt to optimize control loops
• Often breaks end-to-end architecture
• If so, breaks end-to-end reliability (at lease at
  the transport layer)
• Difficulty working with Security (IPSec, Virtual
  Private Networks)

Control Loop 2
Control Loop 1
Control Loop 3
End-to-End Control Loop
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Reliable Transport Protocol Developments

• TCP Swift Start
• Improves Slow Start Performance
• TCP Westwood
• Attacks Additive Increase, Multiplicative
  Decrease (AIMD) problem
• Cumulative Explicit Transport Error Notification
• Attacks Additive Increase, Multiplicative
  Decrease (AIMD) problem
• Stream Control Transport Protocol (SCTP)
• New Reliable Transport Protocol
• Incorporates many proposed improvements to TCP
• Byte Counting
• Selective Acknowledgements
• Non-Blocking of multiple streams

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Internet Trends

• Inexpensive Broadband Connectivity
• Cable Modem, DSL, WiFi, G2.5/G3/G4
• Always On Connectivity
• Peer-to-Peer networking
• Symmetric Links (no longer highly asymmetric)
• Conversation may be initiated from outside your
  network!
• eBusiness
• Web replaces paper forms (e.g. eNASA, eCoast
  Guard)
• Network Centric Warfare
• Mobile Networking
• Maintain connections when crossing networks
• IPv6
• Security
• Network Address Translation and Proxies can
  really mess things up, but are probably here to
  stay.
• Ad Hoc Networking

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What is Mobile-IP and Mobile Networking?

• Mobile IP is a routing protocol that enables
  IPnodes (hosts and routers) using either IPv4 or
  IPv6 to seamlessly roam" among IP subnetworks. 
• Supports transparency above the IP layer,
  including the maintenance ofactive TCP
  connections and UDP port bindings.
• Link Independent
• Supports Multi-Homing (connections to more than
  one route and/or media type)

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Mobile Router uses
Time
Ethernet
Ethernet
FA
FA PortB
FA Port A
NOC HA Carnival Cruise
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Military Applications
Home-Agent deployed in BGCC
Communications link between BGCC and the Field
Command Post
Tactical data forwarded from surveillance
satellites to the BGCC.
Battle Group Command Center (BGCC)
Foreign-Agent deployed in UAV
Intelligence Control Center
Foreign-Agent deployed in Tracked Command Post
Carrier. Unit deployed in vicinity of the
battlefield.
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Hostage House
Request from Headquarters to Cruser when NO
contact via 802.11
Z
Foreign Agent
HQ
Home Agent
Z
Z
Remote Command Center
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Hostage House
Reply from Cruser to Headquarters when NO
contact via 802.11
Z
Foreign Agent
HQ
Home Agent
Z
Z
Remote Command Center
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Securing Networks

• Constraints/Tools
• Policy
• Security Policy
• Education
• Enforcement
• Architecture
• Protocols
• Must be done up front to be done well

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Security

• Security ? Bandwidth Utilization ?
• Security ? Performance ?
• Tunnels Tunnels Tunnels and more Tunnels
• Performance ? Security ?
• ? User turns OFF Security to make system usable!
• Thus, we need more bandwidth to ensure security.

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Conclusions Regarding Security

• Security Breaks Everything ?
• At least it sometimes feels like that.
• The ultimate Denial-of-Service attack. D.S.
• Need to change policy where appropriate.
• Need to develop good architectures that consider
  how the wireless systems and protocols operate.
• If you cannot change policy or architecture, then
  you must change the protocol.
• Possible solutions that should be investigated
• Dynamic, Protocol aware firewalls and proxies.
• Possibly incorporated with Authentication and
  Authorization.

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Satellites and Their Competition

• The Cost of Connectivity

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RF Technologies (Mobile)

• Globalstar (L-Band)
• Globalstar MCM-8 (Client/Server)
• Seatel MCM-3 (Client/Server)
• Qualcomm MDSS-16
• Boeing Connex (Ku-Band)
• INMARSAT Swift 64
• TrackNet 2.0 (Ku-Band)
• G2.5/G3/G4
• General Packet Radio Service (GPRS) 56 kbps
• 1xRTT 110 kbps
• WiFi (802.11)
• VHF

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Satellites vs. The World

• Disadvantage
• Cost to deploy
• Cost of Service
• Time to deploy
• Landing Rights (politics)
• Bandwidth and Frequency reuse
• Point-to-Point Costs
• Incremental deployment may be difficult
• High Link budgets
• Link Delay

• Advantages
• Broadcast / Multicast
• Large Coverage Area
• Physical Security
• Surveillance
• Remote Sensing
• Navigation (Supplemented by Governments and
  Defense Agencies)

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Cost of Connectivity (Examples)
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Deployment issues (mobile)

• Equipment Costs
• Service Cost
• Network Peculiarities
• Network Address Translators
• Performance Enhancing Proxies
• Security Mechanisms
• Packet Filtering
• Connection Mechanisms
• Smart Card Authentication
• MAC and/or Static Key
• (manual login is unacceptable)

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Verizon Wireless Coverage
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T-Mobile Coverage
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Cingular Wireless Coverage
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GSM Coverage - TerrestrialBased on Particular
Service Providers
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Satellite Coverage
Globalstar
INMARSAT
From SaVi
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Typical Ku-Band Coverage
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Applications, Requirements and Costs
Do you need to be connected all the time?
What is "always on" connectivity worth to you?
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Stratospheric Platforms These Are Coming Soon
Refernece Ryu MIURA and Masayuki OOD RD
Program on Telecom and Broadcasting System Using
High Altitude Platform Stations, Journal of the
Communications Research Laboratory Vol.48 No.4
2001
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High Altitude Airships (Platforms) - Coming Soon
-

• 500 feet long, 160 feet in diameter
• Volume of 5.2 million cubic feet, about 25 times
  larger than the blimps seen at athletic events.
• 21.33 km (70,000 feet) elevation
• Payload 1814 kilograms (4000 pounds)
• 10 kWatts power

www.lockheedmartin.com/akron/protech/aeroweb/aeros
tat/haa.htm
The Missile Defense Agency today (Sept 29.2003)
awarded Lockheed Martin (NYSE LMT - News) a 40
million design and risk reduction contract as the
next phase of the advanced technology concept
demonstration to deliver a high altitude airship
(HAA) prototype in 2006
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www.elec.york.ac.uk/comms/presentations/HAPsmainpr
es2000/HAPSmainpres.pdf
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Comments Relative to Mobile Networking

• Fixed Flat-Rate pricing or die
• Price per bit or connect time
• Not manageable
• Impossible to budget
• Voice, Video and Data are all just bits
• Cost of satellite equipment and services
  justifies
• Development of new technologies (e.g. Ad Hoc
  Networks, High Altitude Airships and
  Stratospheric Platforms)
• Deployment of new infrastructure

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Papers and Presentations

• http//roland.grc.nasa.gov/ivancic/papers_present
  ations/papers.html
• or
• http//roland.grc.nasa.gov/ivancic/
• and pick
• Papers and Presentations