Title: Internet Trends and the Cost of Connectivity
1Internet Trends and the Cost of Connectivity
- 1st BroadSky Workshop, Lacco Ameno, Italy
- November 6, 2003
- Will Ivancic wivancic_at_grc.nasa.gov
2Outline
- History of NASA Glenns Space Communications
Program - Internet Over Satellite
- Internet Trends
- Mobile Networks and Security
- Satellites and Their Competition
3NASA 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)
4Experimental 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
5NASA 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)
6Aeronautics
- 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)
7Internet Over Satellite
8Internet 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
9Transmission 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
10Performance 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
11Reliable 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
12Round 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
13Internet 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
14Mobile Networks
15Mobile 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
16What 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)
17Mobile Router uses
Time
Ethernet
Ethernet
FA
FA PortB
FA Port A
NOC HA Carnival Cruise
18Military 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.
19Mobile 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
20Securing Mobile and Wireless Networks
- Constraints / Tools
- Policy
- Architecture
- Protocols
- Must be done up front to be done well
21Security
- 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.
22Conclusions 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.
23Satellites and Their Competition
24Satellites 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)
25RF 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
26Cost of Connectivity (Examples)
27Deployment 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)
29Verizon Wireless Coverage
30T-Mobile Coverage
31Cingular Wireless Coverage
32GSM Coverage - TerrestrialBased on Particular
Service Providers
33Satellite Coverage
Globalstar
INMARSAT
From SaVi
34Typical Ku-Band Coverage
35Applications, Requirements and Costs
Do you need to be connected all the time?
What is "always on" connectivity worth to you?
36Stratospheric 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
37www.elec.york.ac.uk/comms/presentations/HAPsmainpr
es2000/HAPSmainpres.pdf
38High 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
39Comments 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
40Papers 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