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Internet Trends and the Cost of Connectivity

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History of NASA Glenn's Space Communications Program. Internet ... Carnival Cruise. FA. FA. PortB. Ethernet. Ethernet. Time. 18. Military Applications. AWACS ... – PowerPoint PPT presentation

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Title: Internet Trends and the Cost of Connectivity


1
Internet Trends and the Cost of Connectivity
  • 1st BroadSky Workshop, Lacco Ameno, Italy
  • November 6, 2003
  • Will Ivancic wivancic_at_grc.nasa.gov

2
Outline
  • History of NASA Glenns Space Communications
    Program
  • Internet Over Satellite
  • Internet Trends
  • Mobile Networks and Security
  • Satellites and Their Competition

3
NASA Glenns Space Communications Program
  • Experimental Satellites
  • Maintain US preeminence in satellite
    communication
  • Focused on Commercial Communications Satellites
  • Space Communications
  • NASA Mission Focused
  • Earth Science
  • Computer Information and Communications
    Technology (CICT)
  • Human Exploration and Development of Space
  • Aeronautics
  • Capacity (Air Traffic Management)
  • Safety (Weather and Security)

4
Experimental Satellites
  • Communications Technology Satellite (CTS, also
    called Hermes)
  • A joint project by the Canadian Department of
    Communications and NASA.
  • 200 Watt TWT amplifier and operated at 14 up/12
    down GHz (Ku Band).
  • Launch date January 17, 1976.
  • Advanced Communications Technology Satellite
    (ACTS)
  • Ka-Band Spot Beams
  • Onboard Processing
  • Satellite Matrix Switch (500 MHz BW)
  • Majority of the Networking Experiments were
    performed via the matrix switch because for the
    flexibility it provided.
  • Launch date September 12, 1993

5
NASA Missions
  • Earth Science
  • Sensors, Antennas, Communication Protocols
  • CICT Space Communications
  • Intelligent Communication Architectures - Develop
    intelligent, autonomous communication
    technologies that allow "anytime/anywhere"
    operations and deliver information from space
    directly to users.
  • High Rate Backbone Network - Develop advanced
    communication technologies that substantially
    increase data while reducing costs.
  • Flexible Access Network - Develop flexible,
    reconfigurable networks to allow communications
    among NASA's in-space or ground resources.
  • Inter-spacecraft Cooperative Network - Create
    hardware, software, and networks for
    communication among future NASA spacecraft.
  • Proximity Wireless Network - Develop
    ultra-energy-efficient, reliable, miniaturized
    wireless network technologies for robotic
    missions
  • Human Exploration and Development of Space
  • Direct Data Distribution at 622 Mbps (Ka Band)

6
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)

7
Internet Over Satellite
8
Internet Protocols (of greatest interest to NASA)
  • Routing (layer-3, IP)
  • Generally not delay sensitive.
  • Transport (layer-4, Transport)
  • Reliable transport protocols such as TCP may be
    delay sensitive.
  • Security (Everywhere, but of greatest interest
    between layer 3 and 4)
  • May be delay sensitive depending on timer
    settings
  • key exchanges
  • challenges to prevent man-in-the-middle attacks

9
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

10
Performance Enhancing Proxies (PEPs)
  • Middleware deployed to help TCP performance over
    links with large bandwidth-delay products
  • Attempt to optimize control loops
  • Often break 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
11
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
  • New Reliable Transport Protocol
  • Incorporates many proposed improvements to TCP
  • Byte Counting
  • Selective Acknowledgements
  • Non-Blocking of multiple streams

12
Round Trip Time (RTT) Delay
  • US to Japan Terrestrial
  • 20 100 msec
  • GEO Satellite
  • 550 msec
  • 802.11 Wireless Ethernet
  • Negligible (Network Delay Dominates)
  • G2 / G3 Cellular
  • 1 Second using General Packet Radio Services
    (GPRS) from T-Mobile
  • LEO (Using Globalstar)
  • 1 2.5 Seconds

13
Internet Trends
  • Inexpensive Broadband Connectivity
  • Cable Modem, DSL, WiFi, G2.5/G3/G4
  • Always On Connectivity
  • Peer-to-Peer networking
  • Symmetric Links
  • 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.
  • Ad Hoc Networking

14
Mobile Networks
15
Mobile Networking Solutions
  • Routing Protocols
  • ? Route Optimization
  • ? Convergence Time
  • ? Sharing Infrastructure who owns the network?
  • Mobile-IP
  • ? Route Optimization (Basic Implementation)
  • ? Convergence Time
  • ? Sharing Infrastructure
  • ? Security Relatively Easy to Secure
  • Domain Name Servers
  • ? Route Optimization
  • ? Convergence Time
  • ? Reliability

16
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)

17
Mobile Router uses
Time
Ethernet
Ethernet
FA
FA PortB
FA Port A
NOC HA Carnival Cruise
18
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.
19
Mobile Ad-Hoc Networks
  • Self-configure and Self-organize Network
  • Requires common Ad-hoc routing protocol between
    users
  • Requires Common Radios and Media Access between
    Ad-hoc nodes
  • Requires Trust or Authentication between nodes
  • Security is extremely difficult in a truly
    ad-hoc network

20
Securing Mobile and Wireless Networks
  • Constraints / Tools
  • Policy
  • Architecture
  • Protocols
  • Must be done up front to be done well

21
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.

22
Conclusions Regarding Security
  • Security Breaks Everything ?
  • At least it sometimes feels like that.
  • 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.

23
Satellites and Their Competition
  • The Cost of Connectivity

24
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 is difficult
  • High Link budgets
  • Link Delay
  • Advantages
  • Broadcast / Multicast
  • Large Coverage Area
  • Physical Security
  • Surveillance
  • Remote Sensing
  • Navigation (Supplemented by Governments and
    Defense Agencies)

25
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)
  • 1xRTT
  • WiFi (802.11)
  • VHF

26
Cost of Connectivity (Examples)
27
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)

28
(No Transcript)
29
Verizon Wireless Coverage
30
T-Mobile Coverage
31
Cingular Wireless Coverage
32
GSM Coverage - TerrestrialBased on Particular
Service Providers
33
Satellite Coverage
Globalstar
INMARSAT
From SaVi
34
Typical Ku-Band Coverage
35
Applications, Requirements and Costs
Do you need to be connected all the time?
What is "always on" connectivity worth to you?
36
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
37
www.elec.york.ac.uk/comms/presentations/HAPsmainpr
es2000/HAPSmainpres.pdf
38
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
39
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

40
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
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