Содержание
- 2. Lecture 2: roadmap 1.1 what is the Internet? 1.2 protocol layers, service models 1.3 network edge
- 3. What’s the Internet: “nuts and bolts” view millions of connected computing devices: hosts = end systems
- 4. Intermediary Network Devices
- 5. Network Media
- 6. Physical media bit: propagates between transmitter/receiver pairs physical link: what lies between transmitter & receiver guided
- 10. Physical media: coax, fiber coaxial cable: two concentric copper conductors bidirectional broadband: multiple channels on cable
- 11. TAT-14 Cable System Sprint Network Administration System The TAT-14 transatlantic cable system is in full service,
- 19. CS Cable Innovator 1995 Finland (145m*24m), 8500 t fiber optic, 42 day of work (60).
- 24. Topology Diagrams Physical topology diagrams
- 25. Topology Diagrams Logical Topology
- 26. Internet: “network of networks” Interconnected ISPs protocols control sending, receiving of msgs e.g., TCP, IP, HTTP,
- 27. What’s the Internet: a service view Infrastructure that provides services to applications: Web, VoIP, email, games,
- 28. Types of Network Classification of interconnected processors by scale.
- 29. Types of Networks
- 30. Personal Area Network Bluetooth PAN configuration
- 31. Local Area Networks Wireless and wired LANs. (a) 802.11. (b) Switched Ethernet.
- 32. Metropolitan Area Networks
- 33. Wide Area Networks WAN using an ISP network.
- 34. The Internet
- 35. Intranets and Extranets
- 36. Access networks and physical media Q: How to connect end systems to edge router? residential access
- 37. Home and Small Office Internet Connections
- 38. Businesses Internet Connections
- 39. Access net: digital subscriber line (DSL) central office telephone network DSLAM use existing telephone line to
- 40. Access net: cable network cable modem splitter … cable headend frequency division multiplexing: different channels transmitted
- 41. cable modem splitter … cable headend CMTS HFC: hybrid fiber coax asymmetric: up to 30Mbps downstream
- 42. Access net: home network to/from headend or central office wireless devices
- 43. Introduction 1- Enterprise access networks (Ethernet) typically used in companies, universities, etc 10 Mbps, 100Mbps, 1Gbps,
- 44. Wireless access networks shared wireless access network connects end system to router via base station aka
- 45. Traditional Separate Networks
- 46. The Converging Network
- 47. Network Architecture
- 48. Fault Tolerance
- 49. Scalability
- 50. QoS
- 51. Security
- 52. 1- Host: sends packets of data host sending function: takes application message breaks into smaller chunks,
- 53. a human protocol and a computer network protocol: Hi Hi TCP connection response TCP connection request
- 54. What’s a protocol? human protocols: “what’s the time?” “I have a question” introductions … specific msgs
- 55. Rule Establishment
- 56. Message Delivery Options
- 57. Layering of airline functionality layers: each layer implements a service via its own internal-layer actions relying
- 58. Protocol Suites and Industry Standards
- 59. Internet protocol stack application: supporting network applications FTP, SMTP, HTTP transport: process-process data transfer TCP, UDP
- 60. TCP/IP Protocol Suite
- 61. ISO/OSI reference model presentation: allow applications to interpret meaning of data, e.g., encryption, compression, machine-specific conventions
- 62. Why is the Network Layer often called “Layer 3”?
- 63. Distinguishing Points
- 65. The Benefits of Using a Layered Model
- 66. Encapsulation source application transport network link physical segment datagram destination application transport network link physical router
- 67. De-encapsulation
- 68. Message Segmentation
- 69. Message Segmentation
- 70. Network Addresses
- 74. Open Standards
- 75. Internet Standards
- 76. Internet Standards
- 77. Electronics and Communications Standard Organizations
- 78. Internet structure: network of networks End systems connect to Internet via access ISPs (Internet Service Providers)
- 79. Internet structure: network of networks Question: given millions of access ISPs, how to connect them together?
- 80. Internet structure: network of networks Option: connect each access ISP to every other access ISP? connecting
- 81. Internet structure: network of networks Option: connect each access ISP to a global transit ISP? Customer
- 82. Internet structure: network of networks But if one global ISP is viable business, there will be
- 83. Internet structure: network of networks But if one global ISP is viable business, there will be
- 84. Internet structure: network of networks … and regional networks may arise to connect access nets to
- 85. Internet structure: network of networks … and content provider networks (e.g., Google, Microsoft, Akamai ) may
- 86. Introduction Internet structure: network of networks at center: small # of well-connected large networks “tier-1” commercial
- 87. Tier-1 ISP: e.g., Sprint
- 88. Readings Kurose, James F. Computer networking : a top-down approach / James F. Kurose, Keith W.
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