Connecting People To Information 강 사 : 전 필 복 [CCIE # 4244] Connecting People To Information
Curriculum Related to ICRC MSSC Cisco 3800 Inst. & Config. CID SNAM CMTDIMCR AS5200 CIT MCRI ACRC ICRC
Connecting People To Information Course Prerequisites Basic knowledge of networking concepts and terminology Basic knowledge of internetworking concepts
Connecting People To Information Router Ethernet (or LAN) Token Ring FDDI/CDDI Network or wide-area network Serial Graphic Symbols
Connecting People To Information Router ATM switch Personal computer Workstation Macintosh Network management station (CiscoWorks) Graphic Symbols (cont.) Bridge Ethernet switch Router/hub
Connecting People To Information 1980s and 1990s: Internetworks Private Nets and Internet
Connecting People To Information Bridge ATM Switch Ethernet Switch Hub Router Local-Area Networks and Devices Operate within a limited geographic area Allow multiaccess to high-bandwidth media Control the network privately under local administration Provide full-time connectivity to local services Connect physically adjacent devices LANs are designed to:
Connecting People To Information Wide-Area Networks and Devices Operate over geography of telecommunication carriers Allow access over serial interfaces operating at lower speeds Control the network subject to regulated public services Provide full-time and part-time connectivity Connect devices separated over wide, even global, areas WANs are designed to: ATM Switch RouterModem CSU/DSU TA/NT1 Multiplexer stat mux Comm. Server WAN Bandwidth Switch
Connecting People To Information 1990s: Global Internetworking
Connecting People To Information Network Manager Tasks and Goals Design Operations Troubleshooting Connectivity Reliable Performance Management Control Flexibility
The Layered Model
Connecting People To Information 8 Why a Layered Network Model? Reduces complexity Standardizes interfaces Facilitates modular engineering Ensures interoperable technology Accelerates evolution Simplifies teaching and learning Application Presentation Session Transport Network Data Link Physical
Connecting People To Information Layer Functions Network processes to applications Data representation Interhost communication End-to-end connections Addresses and best path Access to media Binary transmission Application Presentation Session Transport Network Data Link Physical
Connecting People To Information Peer-to-Peer Communications HOST AHOST B segments packets frames bits Application Presentation Session Transport Network Data Link Physical Application Presentation Session Transport Network Data Link Physical
Connecting People To Information Application Presentation Session Transport Network Data Link Physical Data Encapsulation Data Application Header Data Presentation Header Data Session Header Data Transport Header Data Network Header Data Frame Header Application Presentation Session Transport Network Data Link Physical
Connecting People To Information Data Encapsulation Example Network Header Segment Header Frame Trailer Data Segment Header Data Frame Header Network Header Segment Header Data message Data Segment Packet Frame (medium dependent) Bits
Connecting People To Information Remaining Chapter Sequence Application Presentation Session Transport Network Data Link Physical Network Applications End-to-End Services Data Transmission Routing
Application, Presentation, and Session Layers
Connecting People To Information Computer Applications Word Processing Presentation Graphics Spreadsheet Database Design/Manufacturing Project Planning Others Application Layer Selects network application to support user’s application Network Applications Electronic Mail File Transfer Remote Access Client/Server Process Information Location Network Management Others
Connecting People To Information Application Layer (cont.) Network Applications Electronic Mail File Transfer Remote Access Client/Server Process Information Location Network Management Others Internetwork Applications Electronic Data Interchange World Wide Web Gateways Special-Interest Bulletin Boards Financial Transaction Services Internet Navigation Utilities Conferencing (Video, Voice, Data) Others Internetwork applications can extend beyond the enterprise
Connecting People To Information Graphics Visual Images PICT TIFF JPEG GIF Presentation Layer Provides code formatting and conversion for applications Text Data ASCII EBCDIC Encrypted Sound Video MIDI MPEG QuickTime login:
Connecting People To Information Network File System (NFS) Structured Query Language (SQL) Remote-Procedure Call (RPC) X Window System NetBios Names Internet Browsers DNA Session Control Protocol (SCP) Session Layer Service Request Service Reply Coordinates applications as they interact on different hosts
Transport Layer
Connecting People To Information Transport Layer Overview Segments upper-layer applications Establishes an end-to-end connection Sends segments from one end host to another Optionally, ensures data reliability
Connecting People To Information Sharing a Transport Connection Transport segments share traffic stream Segments Electronic Mail Electronic Mail File Transfer File Transfer Terminal Session Terminal Session ApplicationApplication PresentationPresentation SessionSession TransportTransport ApplicationPortApplicationPortDataData
Connecting People To Information Connection-Oriented Sessions Synchronize Acknowledge Negotiate Connection Data Transfer (Send Segments) SenderReceiver Connection Established
Connecting People To Information Flow Control Buffer Full Process Segments Buffer OK Buffer Full Process Segments Buffer OK Transmit Not Ready Stop Ready Go Resume Transmission SenderReceiver
Connecting People To Information Reliability with Windowing Window size = 1 Send 1 Receive 1 Ack 2 Send 2 Receive 2 Ack 3 Send 1 Send 2 Receive 1 Receive 2 Window size = 3 Send 3 Receive 3 Ack 4 Send 4 SenderReceiver SenderReceiver
Connecting People To Information Positive Acknowledgment SenderReceiver Send 2 Send 1 Send 3 Ack 4 Send 5 Send 4 Send 6 Ack 5 Send 5 Ack
Connecting People To Information Transport to Network Layer Routed packets End-to-end segments