Contents

  1. Computer Networking A Top-Down Approach
    1. About the Authors
    2. Preface
      1. What’s New in the Seventh Edition?
      2. What Is Unique About This Textbook?
      3. Pedagogical Features
      4. Supplements for Instructors
      5. Chapter Dependencies
      6. One Final Note: We’d Love to Hear from You
    3. Table of Contents
  2. Chapter 1 Computer Networks and the Internet
    1. 1.1 What Is the Internet?
      1. 1.1.1 A Nuts-and-Bolts Description
      2. 1.1.2 A Services Description
      3. 1.1.3 What Is a Protocol?
        1. A Human Analogy
        2. Network Protocols
    2. 1.2 The Network Edge
      1. 1.2.1 Access Networks
        1. Home Access: DSL, Cable, FTTH, Dial-Up, and Satellite
        2. Access in the Enterprise (and the Home): Ethernet and WiFi
        3. Wide-Area Wireless Access: 3G and LTE
      2. 1.2.2 Physical Media
        1. Twisted-Pair Copper Wire
        2. Coaxial Cable
        3. Fiber Optics
        4. Terrestrial Radio Channels
        5. Satellite Radio Channels
    3. 1.3 The Network Core
      1. 1.3.1 Packet Switching
        1. Store-and-Forward Transmission
        2. Queuing Delays and Packet Loss
        3. Forwarding Tables and Routing Protocols
      2. 1.3.2 Circuit Switching
        1. Multiplexing in Circuit-Switched Networks
        2. Packet Switching Versus Circuit Switching
      3. 1.3.3 A Network of Networks
    4. 1.4 Delay, Loss, and Throughput in Packet-Switched Networks
      1. 1.4.1 Overview of Delay in Packet-Switched Networks
        1. Types of Delay
          1. Processing Delay
          2. Queuing Delay
          3. Transmission Delay
          4. Propagation Delay
          5. Comparing Transmission and Propagation Delay
      2. 1.4.2 Queuing Delay and Packet Loss
        1. Packet Loss
      3. 1.4.3 End-to-End Delay
        1. Traceroute
        2. End System, Application, and Other Delays
      4. 1.4.4 Throughput in Computer Networks
    5. 1.5 Protocol Layers and Their Service Models
      1. 1.5.1 Layered Architecture
        1. Protocol Layering
        2. Application Layer
        3. Transport Layer
        4. Network Layer
        5. Link Layer
        6. Physical Layer
        7. The OSI Model
      2. 1.5.2 Encapsulation
    6. 1.6 Networks Under Attack
    7. 1.7 History of Computer Networking and the Internet
      1. 1.7.1 The Development of Packet Switching: 1961–1972
      2. 1.7.2 Proprietary Networks and Internetworking: 1972–1980
      3. 1.7.3 A Proliferation of Networks: 1980–1990
      4. 1.7.4 The Internet Explosion: The 1990s
      5. 1.7.5 The New Millennium
    8. 1.8 Summary
      1. Road-Mapping This Book
    9. Homework Problems and Questions
      1. Chapter 1 Review Questions
        1. SECTION 1.1
        2. SECTION 1.2
        3. SECTION 1.3
        4. SECTION 1.4
        5. SECTION 1.5
        6. SECTION 1.6
      2. Problems
  3. Chapter 2 Application Layer
    1. 2.1 Principles of Network Applications
      1. 2.1.1 Network Application Architectures
      2. 2.1.2 Processes Communicating
        1. Client and Server Processes
        2. The Interface Between the Process and the Computer Network
        3. Addressing Processes
      3. 2.1.3 Transport Services Available to Applications
        1. Reliable Data Transfer
        2. Throughput
        3. Timing
        4. Security
      4. 2.1.4 Transport Services Provided by the Internet
        1. TCP Services
        2. UDP Services
        3. Services Not Provided by Internet Transport Protocols
      5. 2.1.5 Application-Layer Protocols
      6. 2.1.6 Network Applications Covered in This Book
    2. 2.2 The Web and HTTP
      1. 2.2.1 Overview of HTTP
      2. 2.2.2 Non-Persistent and Persistent Connections
        1. HTTP with Non-Persistent Connections
        2. HTTP with Persistent Connections
      3. 2.2.3 HTTP Message Format
        1. HTTP Request Message
        2. HTTP Response Message
      4. 2.2.4 User-Server Interaction: Cookies
      5. 2.2.5 Web Caching
        1. The Conditional GET
    3. 2.3 Electronic Mail in the Internet
      1. 2.3.1 SMTP
      2. 2.3.2 Comparison with HTTP
      3. 2.3.3 Mail Message Formats
      4. 2.3.4 Mail Access Protocols
        1. POP3
        2. IMAP
        3. Web-Based E-Mail
    4. 2.4 DNS—The Internet’s Directory Service
      1. 2.4.1 Services Provided by DNS
      2. 2.4.2 Overview of How DNS Works
        1. A Distributed, Hierarchical Database
        2. DNS Caching
      3. 2.4.3 DNS Records and Messages
        1. DNS Messages
        2. Inserting Records into the DNS Database
    5. 2.5 Peer-to-Peer File Distribution
    6. 2.6 Video Streaming and Content Distribution Networks
      1. 2.6.1 Internet Video
      2. 2.6.2 HTTP Streaming and DASH
      3. 2.6.3 Content Distribution Networks
        1. CDN Operation
        2. Cluster Selection Strategies
      4. 2.6.4 Case Studies: Netflix, YouTube, and Kankan
        1. Netflix
        2. YouTube
        3. Kankan
    7. 2.7 Socket Programming: Creating Network Applications
      1. 2.7.1 Socket Programming with UDP
        1. UDPClient.py
        2. UDPServer.py
      2. 2.7.2 Socket Programming with TCP
        1. TCPClient.py
        2. TCPServer.py
    8. 2.8 Summary
    9. Homework Problems and Questions
      1. Chapter 2 Review Questions
        1. SECTION 2.1
        2. SECTION 2.2–2.5
        3. SECTION 2.5
        4. SECTION 2.6
        5. SECTION 2.7
      2. Problems
        1. Socket Programming Assignments
        2. Assignment 1: Web Server
        3. Assignment 2: UDP Pinger
        4. Assignment 3: Mail Client
        5. Assignment 4: Multi-Threaded Web Proxy
        6. Wireshark Lab: HTTP
        7. Wireshark Lab: DNS
  4. Chapter 3 Transport Layer
    1. 3.1 Introduction and Transport-Layer Services
      1. 3.1.1 Relationship Between Transport and Network Layers
      2. 3.1.2 Overview of the Transport Layer in the Internet
    2. 3.2 Multiplexing and Demultiplexing
    3. 3.3 Connectionless Transport: UDP
      1. 3.3.1 UDP Segment Structure
      2. 3.3.2 UDP Checksum
    4. 3.4 Principles of Reliable Data Transfer
      1. 3.4.1 Building a Reliable Data Transfer Protocol
        1. Reliable Data Transfer over a Perfectly Reliable Channel: rdt1.0
        2. Reliable Data Transfer over a Channel with Bit Errors: rdt2.0
        3. Reliable Data Transfer over a Lossy Channel with Bit Errors: rdt3.0
      2. 3.4.2 Pipelined Reliable Data Transfer Protocols
      3. 3.4.3 Go-Back-N (GBN)
      4. 3.4.4 Selective Repeat (SR)
    5. 3.5 Connection-Oriented Transport: TCP
      1. 3.5.1 The TCP Connection
      2. 3.5.2 TCP Segment Structure
        1. Sequence Numbers and Acknowledgment Numbers
        2. Telnet: A Case Study for Sequence and Acknowledgment Numbers
      3. 3.5.3 Round-Trip Time Estimation and Timeout
        1. Estimating the Round-Trip Time
        2. Setting and Managing the Retransmission Timeout Interval
      4. 3.5.4 Reliable Data Transfer
        1. A Few Interesting Scenarios
        2. Doubling the Timeout Interval
        3. Fast Retransmit
        4. Go-Back-N or Selective Repeat?
      5. 3.5.5 Flow Control
      6. 3.5.6 TCP Connection Management
    6. 3.6 Principles of Congestion Control
      1. 3.6.1 The Causes and the Costs of Congestion
        1. Scenario 1: Two Senders, a Router with Infinite Buffers
        2. Scenario 2: Two Senders and a Router with Finite Buffers
        3. Scenario 3: Four Senders, Routers with Finite Buffers, and Multihop Paths
      2. 3.6.2 Approaches to Congestion Control
    7. 3.7 TCP Congestion Control
      1. 3.7.1 Fairness
        1. Fairness and UDP
        2. Fairness and Parallel TCP Connections
      2. 3.7.2 Explicit Congestion Notification (ECN): Network-assisted Congestion Control
    8. 3.8 Summary
    9. Homework Problems and Questions
      1. Chapter 3 Review Questions
        1. SECTIONS 3.1–3.3
        2. SECTION 3.4
        3. SECTION 3.5
        4. SECTION 3.7
      2. Problems
      3. Programming Assignments
        1. Implementing a Reliable Transport Protocol
        2. Wireshark Lab: Exploring TCP
        3. Wireshark Lab: Exploring UDP
  5. Chapter 4 The Network Layer: Data Plane
    1. 4.1 Overview of Network Layer
      1. 4.1.1 Forwarding and Routing: The Data and Control Planes
        1. Control Plane: The Traditional Approach
        2. Control Plane: The SDN Approach
      2. 4.1.2 Network Service Model
        1. An Overview of Chapter 4
    2. 4.2 What’s Inside a Router?
      1. 4.2.1 Input Port Processing and Destination-Based Forwarding
      2. 4.2.2 Switching
      3. 4.2.3 Output Port Processing
      4. 4.2.4 Where Does Queuing Occur?
        1. Input Queueing
        2. Output Queueing
      5. 4.2.5 Packet Scheduling
        1. First-in-First-Out (FIFO)
        2. Priority Queuing
        3. Round Robin and Weighted Fair Queuing (WFQ)
    3. 4.3 The Internet Protocol (IP): IPv4, Addressing, IPv6, and More
      1. 4.3.1 IPv4 Datagram Format
      2. 4.3.2 IPv4 Datagram Fragmentation
      3. 4.3.3 IPv4 Addressing
        1. Obtaining a Block of Addresses
        2. Obtaining a Host Address: The Dynamic Host Configuration Protocol
      4. 4.3.4 Network Address Translation (NAT)
      5. 4.3.5 IPv6
        1. IPv6 Datagram Format
        2. Transitioning from IPv4 to IPv6
    4. 4.4 Generalized Forwarding and SDN
      1. 4.4.1 Match
      2. 4.4.2 Action
      3. 4.4.3 OpenFlow Examples of Match-plus-action in Action
        1. A First Example: Simple Forwarding
        2. A Second Example: Load Balancing
        3. A Third Example: Firewalling
    5. 4.5 Summary
    6. Homework Problems and Questions
      1. Chapter 4 Review Questions
        1. SECTION 4.1
        2. SECTION 4.2
        3. SECTION 4.3
        4. SECTION 4.4
      2. Problems
        1. Wireshark Lab
  6. Chapter 5 The Network Layer: Control Plane
    1. 5.1 Introduction
    2. 5.2 Routing Algorithms
      1. 5.2.1 The Link-State (LS) Routing Algorithm
        1. Link-State (LS) Algorithm for Source Node u
      2. 5.2.2 The Distance-Vector (DV) Routing Algorithm
        1. Distance-Vector (DV) Algorithm
        2. Distance-Vector Algorithm: Link-Cost Changes and Link Failure
        3. Distance-Vector Algorithm: Adding Poisoned Reverse
        4. A Comparison of LS and DV Routing Algorithms
    3. 5.3 Intra-AS Routing in the Internet: OSPF
    4. 5.4 Routing Among the ISPs: BGP
      1. 5.4.1 The Role of BGP
      2. 5.4.2 Advertising BGP Route Information
      3. 5.4.3 Determining the Best Routes
        1. Hot Potato Routing
        2. Route-Selection Algorithm
      4. 5.4.4 IP-Anycast
      5. 5.4.5 Routing Policy
      6. 5.4.6 Putting the Pieces Together: Obtaining Internet Presence
    5. 5.5 The SDN Control Plane
      1. 5.5.2 The SDN Control Plane: SDN Controller and SDN Network-control Applications
      2. 5.5.2 OpenFlow Protocol
      3. 5.5.3 Data and Control Plane Interaction: An Example
      4. 5.5.4 SDN: Past and Future
    6. 5.6 ICMP: The Internet Control Message Protocol
    7. 5.7 Network Management and SNMP
      1. 5.7.1 The Network Management Framework
      2. 5.7.2 The Simple Network Management Protocol (SNMP)
    8. 5.7 Summary
    9. Homework Problems and Questions
      1. Chapter 5 Review Questions
        1. SECTION 5.1
        2. SECTION 5.2
        3. SECTIONS 5.3–5.4
        4. SECTION 5.5
        5. SECTIONS 5.6–5.7
      2. Problems
        1. Socket Programming Assignment
        2. Assignment 5: ICMP Ping
        3. Programming Assignment
        4. Wireshark Lab
  7. Chapter 6 The Link Layer and LANs
    1. 6.1 Introduction to the Link Layer
      1. 6.1.1 The Services Provided by the Link Layer
      2. 6.1.2 Where Is the Link Layer Implemented?
    2. 6.2 Error-Detection and -Correction Techniques
      1. 6.2.1 Parity Checks
      2. 6.2.2 Checksumming Methods
      3. 6.2.3 Cyclic Redundancy Check (CRC)
    3. 6.3 Multiple Access Links and Protocols
      1. 6.3.1 Channel Partitioning Protocols
      2. 6.3.2 Random Access Protocols
        1. Slotted ALOHA
        2. ALOHA
        3. Carrier Sense Multiple Access (CSMA)
        4. Carrier Sense Multiple Access with Collision Dection (CSMA/CD)
        5. CSMA/CD Efficiency
      3. 6.3.3 Taking-Turns Protocols
      4. 6.3.4 DOCSIS: The Link-Layer Protocol for Cable Internet Access
    4. 6.4 Switched Local Area Networks
      1. 6.4.1 Link-Layer Addressing and ARP
        1. MAC Addresses
        2. Address Resolution Protocol (ARP)
        3. Sending a Datagram off the Subnet
      2. 6.4.2 Ethernet
        1. Ethernet Frame Structure
        2. Ethernet Technologies
      3. 6.4.3 Link-Layer Switches
        1. Forwarding and Filtering
        2. Self-Learning
        3. Properties of Link-Layer Switching
        4. Switches Versus Routers
      4. 6.4.4 Virtual Local Area Networks (VLANs)
    5. 6.5 Link Virtualization: A Network as a Link Layer
      1. 6.5.1 Multiprotocol Label Switching (MPLS)
    6. 6.6 Data Center Networking
    7. 6.7 Retrospective: A Day in the Life of a Web Page Request
      1. 6.7.1 Getting Started: DHCP, UDP, IP, and Ethernet
      2. 6.7.2 Still Getting Started: DNS and ARP
      3. 6.7.3 Still Getting Started: Intra-Domain Routing to the DNS Server
      4. 6.7.4 Web Client-Server Interaction: TCP and HTTP
    8. 6.8 Summary
    9. Homework Problems and Questions
      1. Chapter 6 Review Questions
        1. SECTIONS 6.1–6.2
        2. SECTION 6.3
        3. SECTION 6.4
      2. Problems
        1. Wireshark Labs
  8. Chapter 7 Wireless and Mobile Networks
    1. 7.1 Introduction
    2. 7.2 Wireless Links and Network Characteristics
      1. 7.2.1 CDMA
    3. 7.3 WiFi: 802.11 Wireless LANs
      1. 7.3.1 The 802.11 Architecture
        1. Channels and Association
      2. 7.3.2 The 802.11 MAC Protocol
        1. Dealing with Hidden Terminals: RTS and CTS
        2. Using 802.11 as a Point-to-Point Link
      3. 7.3.3 The IEEE 802.11 Frame
        1. Payload and CRC Fields
        2. Address Fields
        3. Sequence Number, Duration, and Frame Control Fields
      4. 7.3.4 Mobility in the Same IP Subnet
      5. 7.3.5 Advanced Features in 802.11
        1. 802.11 Rate Adaptation
        2. Power Management
      6. 7.3.6 Personal Area Networks: Bluetooth and Zigbee
        1. Bluetooth
        2. Zigbee
    4. 7.4 Cellular Internet Access
      1. 7.4.1 An Overview of Cellular Network Architecture
        1. Cellular Network Architecture, 2G: Voice Connections to the ­Telephone Network
      2. 7.4.2 3G Cellular Data Networks: Extending the Internet to Cellular Subscribers
        1. 3G Core Network
        2. 3G Radio Access Network: The Wireless Edge
      3. 7.4.3 On to 4G: LTE
        1. 4G System Architecture: An All-IP Core Network
        2. LTE Radio Access Network
    5. 7.5 Mobility Management: Principles
      1. 7.5.1 Addressing
      2. 7.5.2 Routing to a Mobile Node
        1. Indirect Routing to a Mobile Node
        2. Direct Routing to a Mobile Node
    6. 7.6 Mobile IP
    7. 7.7 Managing Mobility in Cellular Networks
      1. 7.7.1 Routing Calls to a Mobile User
      2. 7.7.2 Handoffs in GSM
    8. 7.8 Wireless and Mobility: Impact on ­Higher-Layer Protocols
    9. 7.9 Summary
    10. Homework Problems and Questions
      1. Chapter 7 Review Questions
        1. Section 7.1
        2. Section 7.2
        3. Sections 7.3 and 7.4
        4. Sections 7.5 and 7.6
        5. Section 7.7
        6. Section 7.8
      2. Problems
        1. Wireshark Lab
  9. Chapter 8 Security in Computer Networks
    1. 8.1 What Is Network Security?
    2. 8.2 Principles of Cryptography
      1. 8.2.1 Symmetric Key Cryptography
        1. Block Ciphers
        2. Cipher-Block Chaining
      2. 8.2.2 Public Key Encryption
        1. RSA
        2. Session Keys
        3. Why Does RSA Work?
    3. 8.3 Message Integrity and Digital Signatures
      1. 8.3.1 Cryptographic Hash Functions
      2. 8.3.2 Message Authentication Code
      3. 8.3.3 Digital Signatures
        1. Public Key Certification
    4. 8.4 End-Point Authentication
      1. 8.4.1 Authentication Protocol ap1.0
      2. 8.4.2 Authentication Protocol ap2.0
      3. 8.4.3 Authentication Protocol ap3.0
      4. 8.4.4 Authentication Protocol ap3.1
      5. 8.4.5 Authentication Protocol ap4.0
    5. 8.5 Securing E-Mail
      1. 8.5.1 Secure E-Mail
      2. 8.5.2 PGP
    6. 8.6 Securing TCP Connections: SSL
      1. 8.6.1 The Big Picture
        1. Handshake
        2. Key Derivation
        3. Data Transfer
        4. SSL Record
      2. 8.6.2 A More Complete Picture
        1. SSL Handshake
        2. Connection Closure
    7. 8.7 Network-Layer Security: IPsec and Virtual Private Networks
      1. 8.7.1 IPsec and Virtual Private Networks (VPNs)
      2. 8.7.2 The AH and ESP Protocols
      3. 8.7.3 Security Associations
      4. 8.7.4 The IPsec Datagram
        1. Summary of IPsec Services
      5. 8.7.5 IKE: Key Management in IPsec
    8. 8.8 Securing Wireless LANs
      1. 8.8.1 Wired Equivalent Privacy (WEP)
      2. 8.8.2 IEEE 802.11i
    9. 8.9 Operational Security: Firewalls and Intrusion Detection Systems
      1. 8.9.1 Firewalls
        1. Traditional Packet Filters
        2. Stateful Packet Filters
        3. Application Gateway
      2. 8.9.2 Intrusion Detection Systems
        1. Snort
    10. 8.10 Summary
    11. Homework Problems and Questions
      1. Chapter 8 Review Problems
        1. SECTION 8.1
        2. SECTION 8.2
        3. SECTIONS 8.3–8.4
        4. SECTIONS 8.5–8.8
        5. SECTION 8.9
      2. Problems
        1. Wireshark Lab
        2. IPsec Lab
  10. Chapter 9 Multimedia Networking
    1. 9.1 Multimedia Networking Applications
      1. 9.1.1 Properties of Video
      2. 9.1.2 Properties of Audio
      3. 9.1.3 Types of Multimedia Network Applications
        1. Streaming Stored Audio and Video
        2. Conversational Voice- and Video-over-IP
        3. Streaming Live Audio and Video
    2. 9.2 Streaming Stored Video
      1. 9.2.1 UDP Streaming
      2. 9.2.2 HTTP Streaming
        1. Prefetching Video
        2. Client Application Buffer and TCP Buffers
        3. Analysis of Video Streaming
        4. Early Termination and Repositioning the Video
    3. 9.3 Voice-over-IP
      1. 9.3.1 Limitations of the Best-Effort IP Service
        1. Packet Loss
        2. End-to-End Delay
        3. Packet Jitter
      2. 9.3.2 Removing Jitter at the Receiver for Audio
        1. Fixed Playout Delay
        2. Adaptive Playout Delay
      3. 9.3.3 Recovering from Packet Loss
        1. Forward Error Correction (FEC)
        2. Interleaving
        3. Error Concealment
      4. 9.3.4 Case Study: VoIP with Skype
    4. 9.4 Protocols for Real-Time Conversational Applications
      1. 9.4.1 RTP
        1. RTP Basics
        2. RTP Packet Header Fields
      2. 9.4.2 SIP
        1. Setting Up a Call to a Known IP Address
        2. SIP Addresses
        3. SIP Messages
        4. Name Translation and User Location
    5. 9.5 Network Support for Multimedia
      1. 9.5.1 Dimensioning Best-Effort Networks
      2. 9.5.2 Providing Multiple Classes of Service
        1. Motivating Scenarios
        2. The Leaky Bucket
        3. Leaky Bucket + Weighted Fair Queuing = Provable Maximum Delay in a Queue
      3. 9.5.3 Diffserv
      4. 9.5.4 Per-Connection Quality-of-Service (QoS) Guarantees: Resource Reservation and Call Admission
    6. 9.6 Summary
    7. Homework Problems and Questions
      1. Chapter 9 Review Questions
        1. SECTION 9.1
        2. SECTION 9.2
        3. SECTION 9.3
        4. SECTION 9.4
      2. Problems
        1. Programming Assignment
  11. References
  12. Index
    1. A
    2. B
    3. C
    4. D
    5. E
    6. F
    7. G
    8. H
    9. I
    10. J
    11. K
    12. L
    13. M
    14. N
    15. O
    16. P
    17. Q
    18. R
    19. S
    20. T
    21. U
    22. V
    23. W
    24. X
    25. Y
    26. Z

List of Illustrations

  1. Figure 1.1 Some pieces of the Internet
  2. Figure 1.2 A human protocol and a computer network protocol
  3. Figure 1.3 End-system interaction
  4. Figure 1.4 Access networks
  5. Figure 1.5 DSL Internet access
  6. Figure 1.6 A hybrid fiber-coaxial access network
  7. Figure 1.7 FTTH Internet access
  8. Figure 1.8 Ethernet Internet access
  9. Figure 1.9 A typical home network
  10. Figure 1.10 The network core
  11. Figure 1.11 Store-and-forward packet switching
  12. Figure 1.12 Packet switching
  13. Figure 1.13 A simple circuit-switched network consisting of four switches and four links
  14. Figure 1.14
  15. Figure 1.15 Interconnection of ISPs
  16. Figure 1.16 The nodal delay at router A
  17. Figure 1.17 Caravan analogy
  18. Figure 1.18 Dependence of average queuing delay on traffic intensity
  19. Figure 1.19 Throughput for a file transfer from server to client
  20. Figure 1.20 End-to-end throughput: (a) Client downloads a file from ­server; (b) 10 clients ­downloading with 10 servers
  21. Figure 1.21 Taking an airplane trip: actions
  22. Figure 1.22 Horizontal layering of airline functionality
  23. Figure 1.23 The Internet protocol stack (a) and OSI reference model (b)
  24. Figure 1.24 Hosts, routers, and link-layer switches; each contains a ­different set of layers, reflecting their differences in ­functionality
  25. Figure 1.25 A distributed denial-of-service attack
  26. Figure 1.26 An early packet switch
  27. Figure 1.27 End-to-end message transport: (a) without message ­segmentation; (b) with message segmentation
  28. Figure 1.28 A Wireshark screenshot (Wireshark screenshot reprinted by permission of the Wireshark Foundation.)
  29. Figure 2.1 Communication for a network application takes place between end systems at the application layer
  30. Figure 2.2 (a) Client-server architecture; (b) P2P architecture
  31. Figure 2.3 Application processes, sockets, and underlying transport protocol
  32. Figure 2.4 Requirements of selected network applications
  33. Figure 2.5 Popular Internet applications, their application-layer protocols, and their underlying transport protocols
  34. Figure 2.6 HTTP request-response behavior
  35. Figure 2.7 Back-of-the-envelope calculation for the time needed to request and receive an HTML file
  36. Figure 2.8 General format of an HTTP request message
  37. Figure 2.9 General format of an HTTP response message
  38. Figure 2.10 Keeping user state with cookies
  39. Figure 2.11 Clients requesting objects through a Web cache
  40. Figure 2.12 Bottleneck between an institutional network and the Internet
  41. Figure 2.13 Adding a cache to the institutional network
  42. Figure 2.14 A high-level view of the Internet e-mail system
  43. Figure 2.15 Alice sends a message to Bob
  44. Figure 2.16 E-mail protocols and their communicating entities
  45. Figure 2.17 Portion of the hierarchy of DNS servers
  46. Figure 2.18 DNS root servers in 2016
  47. Figure 2.19 Interaction of the various DNS servers
  48. Figure 2.20 Recursive queries in DNS
  49. Figure 2.21 DNS message format
  50. Figure 2.22 An illustrative file distribution problem
  51. Figure 2.23 Distribution time for P2P and client-server architectures
  52. Figure 2.24 File distribution with BitTorrent
  53. Figure 2.25 DNS redirects a user’s request to a CDN server
  54. Figure 2.26 Netflix video streaming platform
  55. Figure 2.27 The client-server application using UDP
  56. Figure 2.28 The TCPServer process has two sockets
  57. Figure 2.29 The client-server application using TCP
  58. Figure 3.1 The transport layer provides logical rather than physical communication between application processes
  59. Figure 3.2 Transport-layer multiplexing and demultiplexing
  60. Figure 3.3 Source and destination port-number fields in a transport-layer segment
  61. Figure 3.4 The inversion of source and destination port numbers
  62. Figure 3.5 Two clients, using the same destination port number (80) to communicate with the same Web server application
  63. Figure 3.6 Popular Internet applications and their underlying transport protocols
  64. Figure 3.7 UDP segment structure
  65. Figure 3.8 Reliable data transfer: Service model and service implementation
  66. Figure 3.9 rdt1.0 – A protocol for a completely reliable channel
  67. Figure 3.10 rdt2.0 – A protocol for a channel with bit errors
  68. Figure 3.11 rdt2.1 sender
  69. Figure 3.12 rdt2.1 receiver
  70. Figure 3.13 rdt2.2 sender
  71. Figure 3.14 rdt2.2 receiver
  72. Figure 3.15 rdt3.0 sender
  73. Figure 3.16 Operation of rdt3.0, the alternating-bit protocol
  74. Figure 3.17 Stop-and-wait versus pipelined protocol
  75. Figure 3.18 Stop-and-wait and pipelined sending
  76. Figure 3.19 Sender’s view of sequence numbers in Go-Back-N
  77. Figure 3.20 Extended FSM description of the GBN sender
  78. Figure 3.21 Extended FSM description of the GBN receiver
  79. Figure 3.22 Go-Back-N in operation
  80. Figure 3.23 Selective-repeat (SR) sender and receiver views of sequence-number space
  81. Figure 3.24 SR sender events and actions
  82. Figure 3.25 SR receiver events and actions
  83. Figure 3.26 SR operation
  84. Figure 3.27 SR receiver dilemma with too-large windows: A new packet or a retransmission?
  85. Figure 3.28 TCP send and receive buffers
  86. Figure 3.29 TCP segment structure
  87. Figure 3.30 Dividing file data into TCP segments
  88. Figure 3.31 Sequence and acknowledgment numbers for a simple Telnet application over TCP
  89. Figure 3.32 RTT samples and RTT estimates
  90. Figure 3.33 Simplified TCP sender
  91. Figure 3.34 Retransmission due to a lost acknowledgment
  92. Figure 3.35 Segment 100 not retransmitted
  93. Figure 3.36 A cumulative acknowledgment avoids retransmission of the first segment
  94. Figure 3.37 Fast retransmit: retransmitting the missing segment before the segment’s timer expires
  95. Figure 3.38 The receive window (rwnd) and the receive buffer (RcvBuffer)
  96. Figure 3.39 TCP three-way handshake: segment exchange
  97. Figure 3.40 Closing a TCP connection
  98. Figure 3.41 A typical sequence of TCP states visited by a client TCP
  99. Figure 3.42 A typical sequence of TCP states visited by a server-side TCP
  100. Figure 3.43 Congestion scenario 1: Two connections sharing a single hop with infinite buffers
  101. Figure 3.44 Congestion scenario 1: Throughput and delay as a function of host sending rate
  102. Figure 3.45 Scenario 2: Two hosts (with retransmissions) and a router with finite buffers
  103. Figure 3.46 Scenario 2 performance with finite buffers
  104. Figure 3.47 Four senders, routers with finite buffers, and multihop paths
  105. Figure 3.48 Scenario 3 performance with finite buffers and multihop paths
  106. Figure 3.49 Two feedback pathways for network-indicated congestion information
  107. Figure 3.50 TCP slow start
  108. Figure 3.51 FSM description of TCP congestion control
  109. Figure 3.52 Evolution of TCP’s congestion window (Tahoe and Reno)
  110. Figure 3.53 Additive-increase, multiplicative-decrease congestion control
  111. Figure 3.54 Two TCP connections sharing a single bottleneck link
  112. Figure 3.55 Throughput realized by TCP connections 1 and 2
  113. Figure 3.56 Explicit Congestion Notification: network-assisted congestion control
  114. Figure 3.57 An incorrect receiver for protocol rdt 2.1
  115. Figure 3.58 TCP window size as a function of time
  116. Figure 4.1 The network layer
  117. Figure 4.2 Routing algorithms determine values in forward tables
  118. Figure 4.3 A remote controller determines and distributes values in ­forwarding tables
  119. Figure 4.4 Router architecture
  120. Figure 4.5 Input port processing
  121. Figure 4.6 Three switching techniques
  122. Figure 4.7 Output port processing
  123. Figure 4.8 HOL blocking at and input-queued switch
  124. Figure 4.9 Output port queueing
  125. Figure 4.10 FIFO queueing abstraction
  126. Figure 4.11 The FIFO queue in operation
  127. Figure 4.12 The priority queueing model
  128. Figure 4.13 The priority queue in operation
  129. Figure 4.14 The two-class robin queue in operation
  130. Figure 4.15 Weighted fair queueing
  131. Figure 4.16 IPv4 datagram format
  132. Figure 4.17 IP fragmentation and reassembly
  133. Figure 4.18 Interface addresses and subnets
  134. Figure 4.19 Subnet addresses
  135. Figure 4.20 Three routers interconnecting six subnets
  136. Figure 4.21 Hierarchical addressing and route aggregation
  137. Figure 4.22 ISPs-R-Us has a more specific route to Organization 1
  138. Figure 4.23 DHCP client and server
  139. Figure 4.24 DHCP client-server interaction
  140. Figure 4.25 Network address translation
  141. Figure 4.26 IPv6 datagram format
  142. Figure 4.27 Tunneling
  143. Figure 4.28 Generalized forwarding: Each packet switch contains a match-plus-action table that is computed and distributed by a remote controller
  144. Figure 4.29 Packet matching fields, OpenFlow 1.0 flow table
  145. Figure 4.30 OpenFlow match-plus-action network with three packet switches, 6 hosts, and an OpenFlow controller
  146. Figure 5.1 Per-router control: Individual routing algorithm components interact in the control plane
  147. Figure 5.2 Logically centralized control: A distinct, typically remote, controller interacts with local control agents (CAs)
  148. Figure 5.3 Abstract graph model of a computer network
  149. Figure 5.4 Least cost path and forwarding table for node u
  150. Figure 5.5 Oscillations with congestion-sensitive routing
  151. Figure 5.6 Distance-vector (DV) algorithm in operation
  152. Figure 5.7 Changes in link cost
  153. Figure 5.8 Network with three autonomous systems. AS3 includes a subnet with prefix x
  154. Figure 5.9 eBGP and iBGP connections
  155. Figure 5.10 Network augmented with peering link between AS1 and AS3
  156. Figure 5.11 Steps in adding outside-AS destination in a router’s ­forwarding table
  157. Figure 5.12 Using IP-anycast to bring users to the closest CDN server
  158. Figure 5.13 A simple BGP policy scenario
  159. Figure 5.14 Components of the SDN architecture: SDN-controlled switches, the SDN controller, network-control applications
  160. Figure 5.15 Components of an SDN controller
  161. Figure 5.16 SDN controller scenario: Link-state change
  162. Figure 5.17 The OpenDaylight controller
  163. Figure 5.18 ONOS controller architecture
  164. Figure 5.19 ICMP message types
  165. Figure 5.20 Elements of network management: Managing server, ­managed devices, MIB data, remote agents, SNMP
  166. Figure 5.21 SNMP PDU format
  167. Figure 6.1 Six link-layer hops between wireless host and server
  168. Figure 6.2 Network adapter: Its relationship to other host components and to protocol stack functionality
  169. Figure 6.3 Error-detection and -correction scenario
  170. Figure 6.4 One-bit even parity
  171. Figure 6.5 Two-dimensional even parity
  172. Figure 6.6 CRC
  173. Figure 6.7 A sample CRC calculation
  174. Figure 6.8 Various multiple access channels
  175. Figure 6.9 A four-node TDM and FDM example
  176. Figure 6.10 Nodes 1, 2, and 3 collide in the first slot. Node 2 finally succeeds in the fourth slot, node 1 in the eighth slot, and node 3 in the ninth slot
  177. Figure 6.11 Interfering transmissions in pure ALOHA
  178. Figure 6.12 Space-time diagram of two CSMA nodes with colliding transmissions
  179. Figure 6.13 CSMA with collision detection
  180. Figure 6.14 Upstream and downstream channels between CMTS and cable modems
  181. Figure 6.15 An institutional network connected together by four switches
  182. Figure 6.16 Each interface connected to a LAN has a unique MAC address
  183. Figure 6.17 Each interface on a LAN has an IP address and a MAC address
  184. Figure 6.18 A possible ARP table in 222.222.222.220
  185. Figure 6.19 Two subnets interconnected by a router
  186. Figure 6.20 Ethernet frame structure
  187. Figure 6.21 100 Mbps Ethernet standards: A common link layer, ­different physical layers
  188. Figure 6.22 Portion of a switch table for the uppermost switch in Figure 6.15
  189. Figure 6.23 Switch learns about the location of an adapter with address 01-12-23-34-45-56
  190. Figure 6.24 Packet processing in switches, routers, and hosts
  191. Figure 6.25 A single switch with two configured VLANs
  192. Figure 6.26 Connecting two VLAN switches with two VLANs: (a) two cables (b) trunked
  193. Figure 6.27 Original Ethernet frame (top), 802.1Q-tagged Ethernet VLAN frame (below)
  194. Figure 6.28 MPLS header: Located between link- and network-layer headers
  195. Figure 6.29 MPLS-enhanced forwarding
  196. Figure 6.30 A data center network with a hierarchical topology
  197. Figure 6.31 Highly interconnected data network topology
  198. Figure 6.32 A day in the life of a Web page request: Network setting and actions
  199. Figure 6.33 Three subnets, interconnected by routers
  200. Figure 7.1 Elements of a wireless network
  201. Figure 7.2 Link characteristics of selected wireless network standards
  202. Figure 7.3 Bit error rate, transmission rate, and SNR
  203. Figure 7.4 Hidden terminal problem caused by obstacle (a) and fading (b)
  204. Figure 7.5 A simple CDMA example: Sender encoding, receiver decoding
  205. Figure 7.6 A two-sender CDMA example
  206. Figure 7.7 IEEE 802.11 LAN architecture
  207. Figure 7.8 An IEEE 802.11 ad hoc network
  208. Figure 7.9 Active and passive scanning for access points
  209. Figure 7.10 802.11 uses link-layer acknowledgments
  210. Figure 7.11 Hidden terminal example: H1 is hidden from H2, and vice versa
  211. Figure 7.12 Collision avoidance using the RTS and CTS frames
  212. Figure 7.13 The 802.11 frame
  213. Figure 7.14 The use of address fields in 802.11 frames: Sending frames between H1 and R1
  214. Figure 7.15 Mobility in the same subnet
  215. Figure 7.16 A Bluetooth piconet
  216. Figure 7.17 Zigbee 802.15.4 super-frame structure
  217. Figure 7.18 Components of the GSM 2G cellular network architecture
  218. Figure 7.19 3G system architecture
  219. Figure 7.20 4G network architecture
  220. Figure 7.21 Twenty 0.5 ms slots organized into 10 ms frames at each frequency. An eight-slot allocation is shown shaded.
  221. Figure 7.22 Various degrees of mobility, from the network layer’s point of view
  222. Figure 7.23 Initial elements of a mobile network architecture
  223. Figure 7.24 Indirect routing to a mobile node
  224. Figure 7.25 Encapsulation and decapsulation
  225. Figure 7.26 Direct routing to a mobile user
  226. Figure 7.27 Mobile transfer between networks with direct routing
  227. Figure 7.28 ICMP router discovery message with mobility agent ­advertisement extension
  228. Figure 7.29 Agent advertisement and mobile IP registration
  229. Figure 7.30 Placing a call to a mobile user: Indirect routing
  230. Figure 7.31 Handoff scenario between base stations with a common MSC
  231. Figure 7.32 Steps in accomplishing a handoff between base stations with a common MSC
  232. Figure 7.33 Rerouting via the anchor MSC
  233. Figure 7.34 Scenario for problem P8
  234. Figure 8.1 Sender, receiver, and intruder (Alice, Bob, and Trudy)
  235. Figure 8.2 Cryptographic components
  236. Figure 8.3 A monoalphabetic cipher
  237. Figure 8.4 A polyalphabetic cipher using two Caesar ciphers
  238. Figure 8.5 An example of a block cipher
  239. Figure 8.6 Public key cryptography
  240. Figure 8.7 Hash functions
  241. Figure 8.8 Initial message and fraudulent message have the same ­checksum!
  242. Figure 8.9 Message authentication code (MAC)
  243. Figure 8.10 Creating a digital signature for a document
  244. Figure 8.11 Sending a digitally signed message
  245. Figure 8.12 Verifying a signed message
  246. Figure 8.13 Trudy masquerades as Bob using public key cryptography
  247. Figure 8.14 Bob has his public key certified by the CA
  248. Figure 8.15 Protocol ap1.0 and a failure scenario
  249. Figure 8.16 Protocol ap2.0 and a failure scenario
  250. Figure 8.17 Protocol ap3.0 and a failure scenario
  251. Figure 8.18 Protocol ap4.0 and a failure scenario
  252. Figure 8.19 Alice used a symmetric session key, KS, to send a secret e-mail to Bob
  253. Figure 8.20 Using hash functions and digital signatures to provide ­sender authentication and message integrity
  254. Figure 8.21 Alice uses symmetric key cyptography, public key ­cryptography, a hash function, and a digital signature to ­provide secrecy, sender authentication, and message integrity
  255. Figure 8.22 A PGP signed message
  256. Figure 8.23 A secret PGP message
  257. Figure 8.24 Although SSL technically resides in the application layer, from the developer’s perspective it is a transport-layer ­protocol
  258. Figure 8.25 The almost-SSL handshake, beginning with a TCP ­connection
  259. Figure 8.26 Record format for SSL
  260. Figure 8.27 Virtual private network (VPN)
  261. Figure 8.28 Security association (SA) from R1 to R2
  262. Figure 8.29 IPsec datagram format
  263. Figure 8.30 802.11 WEP protocol
  264. Figure 8.31 802.11i: Four phases of operation
  265. Figure 8.32 EAP is an end-to-end protocol. EAP messages are encapsulated using EAPoL over the wireless link between the ­client and the access point, and using RADIUS over UDP/IP between the access point and the authentication server
  266. Figure 8.33 Firewall placement between the administered network and the outside world
  267. Figure 8.34 Firewall consisting of an application gateway and a filter
  268. Figure 8.35 Providing anonymity and privacy with a proxy
  269. Figure 8.36 An organization deploying a filter, an application gateway, and IDS sensors
  270. Figure 9.1 Client playout delay in video streaming
  271. Figure 9.2 Streaming stored video over HTTP/TCP
  272. Figure 9.3 Analysis of client-side buffering for video streaming
  273. Figure 9.4 Packet loss for different fixed playout delays
  274. Figure 9.5 Piggybacking lower-quality redundant information
  275. Figure 9.6 Sending interleaved audio
  276. Figure 9.7 Skype peers
  277. Figure 9.8 RTP header fields
  278. Figure 9.9 SIP call establishment when Alice knows Bob’s IP address
  279. Figure 9.10 Session initiation, involving SIP proxies and registrars
  280. Figure 9.11 Competing audio and HTTP applications
  281. Figure 9.12 Policing (and marking) the audio and HTTP traffic classes
  282. Figure 9.13 Logical isolation of audio and HTTP traffic classes
  283. Figure 9.14 The leaky bucket policer
  284. Figure 9.15 n multiplexed leaky bucket flows with WFQ scheduling
  285. Figure 9.16 A simple Diffserv network example
  286. Figure 9.17 A simple Diffserv network example
  287. Figure 9.18 Two competing audio applications overloading the R1-to-R2 link
  288. Figure 9.19 The call setup process

List of Tables

  1. Table 3.1 Summary of reliable data transfer mechanisms and their use
  2. Table 3.2 TCP ACK Generation Recommendation [RFC 5681]
  3. Table 5.1 Running the link-state algorithm on the network in Figure 5.3
  4. Table 5.2 SNMPv2 PDU types
  5. Table 6.1 Comparison of the typical features of popular interconnection devices
  6. Table 7.1 Summary of IEEE 802.11 standards
  7. Table 7.2 Commonalities between mobile IP and GSM mobility
  8. Table 8.1 A specific 3-bit block cipher
  9. Table 8.2 Alice’s RSA encryption, e=5, n=35
  10. Table 8.3 Bob’s RSA decryption, d=29, n=35
  11. Table 8.4 Selected fields in an X.509 and RFC 1422 public key
  12. Table 8.5 Policies and corresponding filtering rules for an organization’s network 130.207/16 with Web server at 130.207.244.203
  13. Table 8.6 An access control list for a router interface
  14. Table 8.7 Connection table for stateful filter
  15. Table 8.8 Access control list for stateful filter
  16. Table 9.1 Comparison of bit-rate requirements of three Internet applications
  17. Table 9.2 Audio payload types supported by RTP
  18. Table 9.3 Some video payload types supported by RTP
  19. Table 9.4 Three network-level approaches to supporting multimedia applications

Landmarks

  1. Frontmatter
  2. Start of Content
  3. backmatter
  4. List of Illustrations
  5. List of Tables
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  2. ii
  3. iii
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  5. v
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