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    • Internet Trends and the Cost of Connectivity 1 st BroadSky Workshop, Lacco Ameno, Italy November 6, 2003 Will Ivancic – [email_address]
      • 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)
      NASA Glenn’s Space Communications Program $$$ $$$ $$$
    • 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…)
    • 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
    • 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)
    • 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 1 Control Loop 3 Control Loop 2 End-to-End Control Loop Internet Internet PEPs
    • 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
    • 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
    • What is Mobile-IP and Mobile Networking?
      • Mobile IP is a routing protocol that enables IP nodes (hosts and routers) using either IPv4 or IPv6 to seamlessly “roam" among IP subnetworks. 
        • Supports transparency above the IP layer, including the maintenance of active TCP connections and UDP port bindings.
        • Link Independent
        • Supports Multi-Homing (connections to more than one route and/or media type)
    • Mobile Router uses FA Port A NOC HA Carnival Cruise FA FA PortB Ethernet Ethernet Time
    • Military Applications Intelligence Control Center Battle Group Command Center (BGCC) Home-Agent deployed in BGCC Foreign-Agent deployed in UAV Foreign-Agent deployed in Tracked Command Post Carrier. Unit deployed in vicinity of the battlefield. Tactical data forwarded from surveillance satellites to the BGCC. Communications link between BGCC and the Field Command Post AWACS UAV Mobile-Router deployed in Armored Field Unit. Secondary communications link utilized due to lost LOS of primary. Non-preferred-path becomes preferred-path Preferred-path Non-preferred-path In case of communications loss of preferred-path Mobile-Router deployed in Armored Field Unit.
    • Z Z Foreign Agent Home Agent HQ Hostage House Z Request from Headquarters to Cruser when NO contact via 802.11 Remote Command Center INTERNET
    • Z Z Foreign Agent Home Agent HQ Hostage House Z Reply from Cruser to Headquarters when NO contact via 802.11 Remote Command Center INTERNET
    • Securing Networks
      • Constraints/Tools
        • Policy
          • Security Policy
          • Education
          • Enforcement
        • Architecture
        • Protocols
      • Must be done up front to be done well
    • 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.
    • 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.
    • Satellites and Their Competition The Cost of Connectivity
    • 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
    • Satellites vs. The World
      • Advantages
        • Broadcast / Multicast
        • Large Coverage Area
        • Physical Security
        • Surveillance
        • Remote Sensing
        • Navigation (Supplemented by Governments and Defense Agencies)
      • 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
    • Cost of Connectivity (Examples)
    • 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)
    • Verizon Wireless Coverage
    • T-Mobile Coverage
    • Cingular Wireless Coverage
    • GSM Coverage - Terrestrial Based on Particular Service Providers
    • Satellite Coverage Globalstar From SaVi INMARSAT
    • Typical Ku-Band Coverage
    • Applications, Requirements and Costs Do you need to be connected all the time? What is "always on" connectivity worth to you? 128 kbps 550 msec RTT 11 Mbps ~50 msec RTT
    • Refernece: Ryu MIURA and Masayuki OOD: “R&D Program on Telecom and Broadcasting System Using High Altitude Platform Stations,” Journal of the Communications Research Laboratory Vol.48 No.4 2001 Stratospheric Platforms – These Are Coming Soon –
    • 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/aerostat/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
    • www.elec.york.ac.uk/comms/presentations/HAPsmainpres2000/HAPSmainpres.pdf
    • 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
    • Papers and Presentations
      • http://roland.grc.nasa.gov/~ivancic/papers_presentations/papers.html
      • or
      • http://roland.grc.nasa.gov/~ivancic/
      • and pick
      • “ Papers and Presentations”