Network Evolution to the New Millenium
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Transcript of Network Evolution to the New Millenium
Habib Youssef 1
Habib Youssef, Ph.D
[email protected] of Computer Engineering
King Fahd University of Petroleum & MineralsDhahran, Saudi Arabia
Network Evolution to the New Millenium
Habib Youssef 2
Outline
Introduction
Operator Challenges and Requirements
Network Convergence and Consequences
Glimpses at some new developments» Web Switching» ASP» Wireless Broadband Access» The Networked Home
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Introduction Over the last few decades technological advances in
telecommunication and computing have been happening at a breathtaking pace.
As we enter a new millenium, network operators are facing important challenges:» Enhance the network in the face of explosive growth in data
traffic and demand of higher bandwidths.» The Internet has become a worldwide phenomenon which is
driving forward the need for extra bandwidth to cope with new multimedia services (text, voice, and still/video images).
– Most of the optical highways are being deployed to cope with the increasing Internet traffic (World Wide Web traffic).
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Introduction (contd.)
However, it is not economical for network operators to focus their evolution on the provision of Internet services only, since most of their revenues are still coming from voice services.
Hence, established operators are being forced to partner with a telecommunication operator with long-standing experience in the provision of both voice and data networking services.» Such a partner will help them determine the right mix of
network investment to cope with growth in IP traffic,» in the longer term, it will help them move toward a common
network infrastructure (Network convergence).
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Forecast revenues from voice and data services (Source: Yankee Group)
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1997 1998 1999 2000 2001 2002
152159 167
176185 194
15 18 2328
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US Dollars(Billions)
Voice Data
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Challenges faced by Operators
How to cope with explosive IP traffic How to optimize revenues from both data and
voice services Which services are genuinely useful to the end
users (residential or corporate) Optimum migration strategy towards an open
network with servers and intelligence that links the data and voice worlds (network convergence)
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Network services In developing network services, operators must
remember that,» Services are developed for users
– Should be simple to use provide users with easy ways of customizing their usage profiles
– Knowledge is more important than information services should be more data-centric rather than purely
communication-centric. Hence, databases and data-mining tools will become key assets.
– Access devices Today telephone handsets and computers are the main access
devices. However, in the future, access will be provided via a wider range of devices ==> Information must be aggregated and generated by a service in such a way that it can be decoupled from the interaction with the device.
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Operator Requirements
Internet Service Providers» Many operators are also ISPs whose short term
objective is to increase profit by optimizing the cost of deploying and providing access to current services
» In the long term, operators must seek to provided new value-added services in order to increase profit, e.g.
– VPNs– Broadband RAS– Managed Firewalls,– VoIP– ASPs
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Operator Requirements (Contd.)
Local Exchange Carriers need a network that can support a mix of services and technologies, not just IP traffic» Switches/Routers that support both IP and ATM» Circuit emulation for leased lines» Frame Relay internetworking» ATM support» Voice over IP» Asymmetric Digital Subscriber Line (ADSL)» Wireless access and mobility
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Wireless Access/Internet
We live in the “Information Era”, where pervasive access to information is becoming a necessity anytime and anywhere» Commercial illustrating importance of Internet anytime:
– Young man who jumped from an airplane but couldn’t get his parachute to open.
He pulls his PDA device and connects to his insurance company web site to increase the limit on his term life insurance
Access to the Internet from a wide range of mobile devices» PDAs, Cellular phones, pagers, in-car computers, etc
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Wireless Access/Internet (Contd.)
Current common properties of these devices» Small screens, low power, little memory, limited
keyboard, low bandwidth– Special protocols and data formats– See
http://www.wirelessinstitute.com/standards.html http://www.wapforum.org
» WAP Forum is focusing on creating a global wireless protocol specification that works across different wireless technologies, for adoption by appropriate industry standards bodies
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Fixed Wireless Internet Access
Interim solution for businesses/homes that don’t have access to CATV or DSL broadband access» Unlike traditional mobile wireless technologies, fixed-
wireless technologies are not designed for use with smart phones, PDA’s, or other similar devices
An ISP using fixed-wireless technology» Sends data from central office or base station optical fiber to
base station antennas» The base station antennas convert the optical signals into high-
frequency radio microwaves for transmission to the antennas of customers in the same cell as the base station antennas
» Te customer’s antenna captures the signal and passes it to the network interface unit , which converts the radio waves to electronic signals and streams them to the receiving computer
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Global Wireless Market
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Users (M)
$$ (B)
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Wireless Market Potentials
Canada» In 1994: 2.7 million wireless users» In 2000: 11.8 million wireless users
Saudi » In 1998: around half million» In 2001: around two million
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The case for Satellite access
Until about 60 years ago» Each individual communicated with about 100
persons, of which 80-90% lived nearby About 20 years ago, these figures changed
» Each individual communicated with as much as 500 other individuals, of which 80-90% are far apart.
The 90’s have seen the emergence of Information Technology which integrates telecommunications, computing, TV, videoconferencing, and consumer electronics in every location (home or business)
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The case for Satellite access (Contd.)
The challenge is to provide » Multi-application networks» Broadband access to everybody (2 Mbps and more)
Terrestrial networking solutions cannot meet all requirements » Wide area multicasting and broadcasting is not easy» A large investment is required to bridge the last mile
between the customer and the local exchange There is a growing belief that Satellites can play a
complementary role in reducing the time-to-market» The subscriber has only to install a satellite terminal and
subscribe to the service via a satellite in orbit
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The case for Satellite access (Contd.)
Wide bandwidth is already available in millions of homes (over 40 milllions in Europe alone) » Existing home installations can be used to a connect
Satellite Interactive Terminals (SITs)» Such services will be provided by satellite onboard
processing (OBP) systems Existing telephone networks are limited in
providing wide access to subscribers» More than two thirds of the investment of a telephone
network is required for the last mile » Investments in the order of 10’s or 100’s of Billion
Dollars to implement the last mile with optical fiber
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The case for Satellite access (Contd.)
Cable TV companies have an installed base of high-bandwidth transmission media (coax) for one-way distribution to subscribers. However» density is much less than the telephone network» A merging of telephone and CATV technologies has
been taking place To provide high-bandwidth to everybody
everywhere requires» Huge investment» Time
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The case for Satellite access (Contd.)
Network technicians would recommend» Asynchronous Transfer Mode (ATM)
Telecommunications managers would recommend temporary solutions such as
– Asynchronous Digital Subscriber Line (ADSL) – High speed/rate Digital Subscriber Line (HDSL) – Very High speed/rate Digital Subscriber Line (VDSL)
More cost effective solution seems to be Satellite access» Terrestrial network would continue to serve telephony
applications» Satellites will be providing the wideband access needed
by multimedia (interactive) services
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Growth in Network Usage
The World wide web has permanently changed networking.
Millions of individual users access the internet from home regularly
Home offices are on the increase Businesses are using the Internet for
commerce. Increasingly, individual organizations are
maintaining their own intranets
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Internet User Growth
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00 00 00 001996
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World Wide Web Users in Millions
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Trends in Applications
Web pages now provide animated graphics, audio & video.
Ease of use is expected of applications. Number of functions are expected from a single
application (e.g., Web browsing, Mailing, Calendaring etc.).
Diverse data types are expected to be handled by a single application (e.g., Documents embedding spread sheets, graphics, voice etc.)
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Trends in Applications E-commerce
» E-Business– Building & maintenance of a complete Web Storefront – Electronic banking & cash
Electronic banking will displace checks & cash in commerce
– E-trade» E-contact to create the “Cyber-salesperson”
– Need for an integrated call center to establish the human touch in cooperation with web access
– Collaborative browsing and multimedia access» E-branch to reach out to the places needed by the
business
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Trends in Applications (Contd.) Videoconferencing Telecommuting
» The E-office– Employees will perform jobs from remote locations
Distant learning Online publishing
» Majority of books & other publications will be online Entertainment on demand
» Movies, TV shows, Sports …. on demand
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Technology Drivers Traffic is doubling every 9 months, while
processing capacity is doubling every 18 months.» Rely on caching whenever possible!» Good data mining!
0200400600800
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1990 1992 1994 1996 1998 2000
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Technology Trends Devices capable of integrating a number of
technologies are being designed and produced e.g. a single switch may interface ATM, FDDI, and Fast/Gigabit Ethernet.
Layer 2 and Layer 3 (IP switches) are being designed and produced.
To meet increased bandwidth needs and application sophistication new standards are being proposed.
Devices capable of prioritizing and filtering are becoming available.
Applications aware switching devices.
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Technology Trends (Contd.) Increased ASICs usage to minimize size and improve
performance. Integration of a wide range of functions, thereby
simplifying networks and reducing operating expenses. Use of an open software platform, making it possible to
integrate best available applications. The Universal Mobile Telecommunication System (UMTS)
» to offer voice and mobile multi-media to the mass market (3rd Generation Mobile systems or 3G)
Networked Home
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Web Switching A new generation of networking devices
specifically designed to address the unique requirements of Web traffic.
They use URLs in addition to IP addresses to make switching decisions.
They are smart switches armed with» sophisticated URL load balancing capabilities» Network address translation» embedded DNS intelligence» use complex policies to manage and speed web traffic
flows
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Web Switching (contd.)
They use URLs in addition to IP addresses to make switching decisions.» URLs provide a ubiquitous method to identify content
across the Internet» Since a URL identifies only the content requested, not
its location, so instead of viewing the IP address associated with this URL as the network address where the content/service is located, this address points to the virtual IP address of the web switch, which functions as a cache or content traffic manager.
» By looking deep into the HTTP payload down to the URL, a Web switch knows what content is being requested
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Web Switching (contd.)
The knowledge of what content is being requested allows a Web switch to know» which user-defined and/or pre-set security policies
must be enforced» which content is to be allowed or denied, and» which QoS requirements are needed for specific
content or even users.
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Web Switching (contd.)
As the VIP address for a WEB site, Web switches intercept all traffic destined for that site» this permits them to predict hot-content before
servers become crowded.» Web switches dynamically replicate hot content to a
Web cache.» Further, a Web switch tracks which servers have
delivered specific content, and therefore, new requests for that content can be sent directly to them resulting in improved server cache coherence/performance.
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TechnologyEssential Technology characteristics to support future applications A variety of access technologies
» wireless, cellular mobile, digital loop carrier, cable modem, IP, ATM, etc.
Manageability» Policy responsive network, administrative partitioning
Scalability» Cost effective growth, bandwidth on demand, Usage &
application based prioritization, multi vendor solutions
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Technology (Contd.)
Reliability» Utility like uptime, self healing networks, embedded
security enforcement Next generation features & services
» Advanced application functionality, ability to easily create new applications & services
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Standardization Efforts Standards are necessary to maintain flexibility & to
avoid the clutches of proprietary designs. Some standards:
» ITU: H323– Supports packet switched networks to carry telephony
traffic» IEEE: 802.1p, 802.1Q
– Support prioritization of data traffic at layer 2, this enables QoS
» IETF: RTP, ISLL, RTSP– Real-time Transport Protocol, Integrated Services over
Specific Link Layers & Real-Time Streaming Protocol enable IP networks to carry multimedia traffic
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Case Example
Head OfficeNetwork
Internet
Branch OfficeNetwork
Branch OfficeNetwork
Leased Line/VPN
Leased Line / VPN
Leased Line/VPN
Why should the company pay for separate inter-branch telephone charges when the VPN
could carry voice traffic?
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Result : Network Convergence
Converged networking is an emerging technology thrust that integrates voice, video
& data traffic over a single network
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Network ConvergenceNetwork Convergence entails convergence in various
aspects e.g. Payload Convergence
» Different data types are carried in same communications format (e.g., layer 1 audio & video streams as well as layer 3 packets may be carried in layer3 datagrams )
Protocol Convergence» The move is away from multi-protocols to a single protocol
namely IP Physical Convergence
» All payloads travel over the same physical network (QoS & CoS may however be used to differentiate service requirements
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Network Convergence (Contd.) Device Convergence
» A single switch may support Ethernet packet forwarding, IP routing, ATM etc.
Application Convergence» A single application integrates formerly separate functions
(e.g., Web pages allow interactive communication) Technology Convergence
» Same technology (e.g., ATM) is used for both LANs & WANs Organizational Convergence
» Centralization of networking, telecommunication & computing services under a single authority
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Converged Network Architecture
A large converged network will probably be composed of LANs and WANs
They will not be homogenous networks, due to:» Differing economic and performance requirements
over LANs and WANs» Differing bandwidth, delay and jitter requirements
Two possible scenarios are presented.
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Converged Network Example 1
Edge network: Switched or routed Ethernet
Core Network: ATM or Frame Relay etc. LAN Edge Network LAN Edge Network
WAN core network
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Converged Network Example 2
Parallel core networks Traffic is filtered into
different service classes at exit from LAN, and routed via different networks:» Connection oriented ATM
for multimedia traffic» Packet switched WAN for
bursty LAN traffic
LAN Edge Network LAN Edge Network
ATM
Packet Switched WAN
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Information Information Delivery Delivery
(Multicast)(Multicast)
Bandwidth Conservation (e.g., Multicast IP)
Supported in: New Routers, Core & Edge Switches NICs
• Multicast IP BenefitsMulticast IP Benefits– Conserves backbone bandwidthConserves backbone bandwidth
– No administration required: automaticNo administration required: automatic
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DA SA TRTR VLAN IDVLAN IDPrPr Information
2 Byte 802.1Q Tag2 Byte 802.1Q Tag
802.1p: 3 Bits802.1p: 3 Bits
Prioritization Technologies
In the switched LAN: 802.1p/Q» 8 levels of priority» Applied to Ethernet packet header» State of standards
– Unanimous approval of draft
In the routed WAN: IP ToS» 8 levels of priority» Applied to IP header» State of standards: Has been a
standard for years
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Guidelines for Application PrioritizationGuidelines for Application Prioritization
7 Systems Management7 Systems Management
6 Real-time Video6 Real-time Video
5 Voice5 Voice
4 Business-Critical4 Business-Critical
0, 3 Best Efforts0, 3 Best Efforts
2 Less than Best Efforts2 Less than Best Efforts
1 Background1 Background
High-PriorityHigh-PriorityQueueQueue
Low-PriorityLow-PriorityQueueQueue
Prioritization Guidelines
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Single QueueSingle Queue
Dual QueueDual Queue
HighHigh
LowLow
Switches that Support Multiple Queues
Multiple queues in all new core & edge switches» Built into hardware» 802.1p tags, without multiple queues, cannot provide priority
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Summary
TechnologyDeregulation/
Convergence
User Growth & Appl. Sophistication Standardization
Evolution in Network And Services
Explosive increase in Transmission Bit Rates And Switching Capacities
Abundant Computing power, DSP, Compression etc.
Distributed operating systems, Middleware, Intelligent agents, Real time database systems.
Globalization, Deregulation
Increased competition, Partnerships
Rapid introduction of Revenue
generating services
Anytime, Anywhere, Anymedia
connectivity, transparency, Flexibility, manageability, Reliability
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Networked Home Networking technologies are starting to invade the
home to link computers and tap into the Internet, to carry phone signals and TV programs, and communicate with home appliances, surveillance cameras, air conditioning units, lights, etc.
Now, prime candidates for home networks are homes with two or more computers.» In the US, homes with two or more computers are
estimated to total 17 millions.» Physical basis for these networks: VG TP, Cat-5 UTP,
electrical power lines, wireless schemes (in the unlicensed 2.4 GHz range)
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Networked Home (Contd.) Projected revenues in the US market:
» Home data and entertainment networking -- By 2001, will hit $725 million (Karuna Uppal, Yankee Group, Boston).
» The biggest market right now for home networking in US involves control: heating, ventilating, and air-conditioning systems; lighting; pumps and sprinklers; and security. Total spending is expected to top $2.75 billion by the end of 2000 (Navin Shabharwal, Allied Business Intelligence).
Players» Start-ups or have been in the business for a short time.» Well established multi-billion Dollar companies such as
Cisco, Intel, Nortel, Motorola, Lucent, 3Co, IBM, and Panasonic
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Networked Home (Contd.) Difficulties
» Lack of useful wiring in a residential network» There is no single affordable medium that meets all
requirements Some new homes in the US are being built with
home networking in mind, namely according to structured wiring standards.» With structured wiring, the communication lines
come into the office at a single point - the wiring closet - and radiate-out from there.
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Homes with structured wiring in the US (The Yankee Group)
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IBM Home Director Products Home Director consists of
» a connection center that sits in the wiring closet» control modules and connectors
Through the center it is possible to control and manage all of the various computers and devices on the network.
The system allows for asserting control from any point on the network and remotely from the Internet.
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Home Structured Network
Connection Center
NetworkGateway
Cat-5Phone lines
WirelessPower line
TV Stereo
Telephones
Mobile Phone
Lightingcontrol
Surveillancecamera
Thermostats
Broadband
ServicesCable modem/ADSL modem/
Satellite receiver/Wireless transceiver/
combination
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Home-networked households in the US in thousands
Phone line
Power line
Wireless
6.5%
81%
75%
87%
92%
70%
1.5%
6.5%
1.5%
6.5%
1.5%
6.5%
1.5%
6.5%
1.5%
1999Total: 600
2000Total: 1321
2001Total: 2478
2002Total: 3998
2003Total: 6006
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To be continued...