CSE%205346%20

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CSE 5346 Networks II High Performance
Networks
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Introduction

• Performance and Quality of Service

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Course Foundation Assumptions (pre-requisites)

• Good understanding of packet-switched networking
  concepts and principles of operation
• Good understanding of Internet protocols and
  architectures (e.g., IP protocol stack)
• Solid foundation in computer operating systems
  fundamentals
• Ability to learn simple programming languages
  (such as ns/2 tcl, C/C)
• Ability to perform independent research, analyze
  findings and document results

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What will we cover?

• Networking Introduction/Review
• Today setting the stage
• Frame Relay, ATM High Speed LANs
• Performance Modeling and Estimation
• Congestion, Network Traffic Analysis/Management
  and Routing
• Quality of Service
• Compression Standards and Practice
• Advanced Topics (time permitting) VoIP, Mobile
  IP, Mobile Agents

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How will we cover it?

• Classroom lectures
• Quizzes and exams
• Incremental modeling and simulation project using
  ns/2
• Self-study research, and simulation reports by
  students
• Study and student presentations on relevant
  papers RFCs

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Chapter 1 - Introduction

• An Overview of Networking - the Need for Speed
  and Quality of Service

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The Evolution of Networks Internetworking

• ARPANET to Internet
• Initial packet switched technology
• DOD ARPA funded
• 4 nodes in 1969 _at_ 50kbps
• TELNET FTP first standard network applications
• 1972 Killer App email!

• Internet to WWW
• Cerf Kahn TCP, 1974
• ARPANET NCP to TCP, 1982-1983
• NSF backbone
• ARPANET shut down, 1990
• Mosaic 1992
• U.S. Government Internet funding terminated in
  1995

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Growth of the Internet
As of January 2005 gt 300 million computers
in 209 countries
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What is an/the Internet?

• connected computing devices hosts, end-systems
• PCs, workstations, servers
• PDAs, phones, toasters, cars
• running network applications
• communication links
• fiber, copper, radio, satellite
• routers/switches forward packets (chunks) of
  data thru network

router
workstation
server
mobile
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The Need for Speed!

• Scale
• growing number of hosts -gt growing demands on
  bandwidth
• new technologies result in new paradigms for
  device and connection types
• e.g. ??

• Application
• demand for large to huge file transfers
• increasing critical nature of Internet use
• demand for real-time performance
  characteristics
• demand for guarantees of service levels
• e.g. ??

• User Expectations!

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High-Speed Networks IDN to ATM

• IDN (Integrated Digital Network)
• early 60s, answer to growth of digital,
  computer-controlled, circuit-switched networking
• WE 4ESS introduced in 1976, 1st large scale
  commercial time-division switch
• ISDN (Integrated Services Digital Network)
• integrated voice and data on the same digital
  transmission links/exchanges
• small incremental cost for data over existing
  digital voice network

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High-Speed Networks IDN to ATM

• Frame Relay
• popularized standard (c. 1988) for packet
  switching over ISDN
• most widely deployed WAN technology in use today
• B-ISDN (Broadband ISDN)
• c. 1988 emerging demand for broadband services
• new high-speed technologies available
• emerging bandwidth hungry applications

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High-Speed Networks IDN to ATM

• ATM (Asynchronous Transfer Mode)
• early 90s outgrowth of emerging need for
  high-speed switching over B-ISDN WAN
• rapidly evolved as high-speed packet switching
  technology of its own accord
• primary deployment today is
• public network infrastructure
• LAN backbone
• private network, VPN WAN
• services not widely deployed/available until
  late-90s.

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High-Speed Networks ATM Backbone Example
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High-Speed Networks LANs

• High-speed LANs
• driven by explosive growth in speed and computing
  power of PCs in 1990s
• emergence of client-server computing architecture
• use of centralized server farms
• emergence of power workgroups and workgroup
  applications
• need for local high-speed LAN backbones

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IP-based Internets (aka TCP/IP networks)

• Internetworking the dominant paradigm of
  computer networking
• Evolution - key internetworking
• technologies
• packet switching
• TCP/IP
• TCP reliable end-to-end transport
• IP internet routing and delivery
• dynamic routing, load balancing
• high speed Ethernet LANs

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Advancements in TCP/IP Networks

• Recent advancements driven by the need to support
  multimedia and real-time traffic
• Emergence of Internets Integrated Services
  Architecture (ISA, or IntServ) and Differentiated
  Service (DS, or DiffServ)
• New QoS Architecture/Framework is driving
  protocol changes
• IPv6 introduces new features for QoS
• RSVP Resource ReSerVation Protocol
• RTP Real Time Protocol
• Multicast routing (IGMP, MOSPF, PIM)
• Multi-Protocol Label Switching (MPLS)

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The Need for Improved (better) Levels of Service

• Applications
• often create inelastic traffic
• often sensitive to delay
• often sensitive to jitter
• often critical in nature
• generate elastic traffic as well

• Internet Best-Effort Service
• all packets treated equally
• designed for elastic traffic
• no guarantees of bandwidth or throughput
• no guarantees of delay
• no guarantee of jitter (delay variation)

• User Requirements!

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Delay Sensitivity Criticality
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Delays in Packet Switched (e.g. IP) Networks

• End-to-end delay (simplified)
• (dprop dtrans dqueue dproc) x Q

• Where
• Propagation delay (dprop)
• Transmission delay (dtrans)
• Queuing delay (dqueue)
• Processing delay (dproc)
• Number of links (Q)

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So whats the problem?
What makes this so hard? (I.e., what are we going
to focus on in this course.)
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Delays in Packet Switched (e.g. IP) Networks

• End-to-end delay (simplified)
• (dprop dtrans dqueue dproc) on each link

• Where
• Propagation delay (dprop) d/s
• Transmission delay (dtrans) L/R
• Queuing delay (dqueue) ?
• Processing delay (dproc) ?
• Number of links (Q) ?