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TCOM 5272 Telecomm Lab Dr. Mostafa Dahshan OU-Tulsa 4W 2nd floor 660-3713 [email protected] M. Dahshan - TCOM5272 1 Acknowledgments Most of the contents of this presentation are imported from Supplemental materials of the textbook Presentations of Dr. Anindya Das M. Dahshan - TCOM5272 2 Introduction Course Objectives Implementation of the theory Improve knowledge in network devices management Introduce some useful software tools Schedule M. Dahshan - TCOM5272 3 Network Types Local area networks (LANs) Metropolitan area networks (MANs) Wide area networks (WANs) M. Dahshan - TCOM5272 4 LAN (Local Area Network) Interconnects computers, printers, other equipment Consists of shared hardware and software resources in close physical proximity Example: TCOM Department M. Dahshan - TCOM5272 5 MAN (Metropolitan Area Network) Spans a greater distance than a LAN Links multiple LANs within city or metropolitan region Typically uses fiberoptic/wireless connections Example: Campus LAN links to offices outside the campus M. Dahshan - TCOM5272 6 WAN (Wide Area Network) Composed of two or more LANs or MANs May have constituent LANs on different continents Example: The Internet M. Dahshan - TCOM5272 7 M. Dahshan - TCOM5272 8 Network Topologies Main topologies: Bus Ring Star Mesh Hybrid topologies star-bus star-ring M. Dahshan - TCOM5272 9 Bus Topology Consists of cables connecting PCs or file servers Visualizes connections as chain links Terminator attached to each end of bus cable segment Media type (discussed later) 10Base5 10Base2 M. Dahshan - TCOM5272 10 Bus Topology (2) Advantages Requires less cable than other topologies Easy to extend bus with a workstation Disadvantages High management costs Single defective node can take down entire network Can become quickly congested with network traffic M. Dahshan - TCOM5272 11 Ring Topology Continuous data path Workstations attached to cable at points around ring Transmitted data Goes around ring to reach destination Continues until ends at source node M. Dahshan - TCOM5272 12 Ring Topology (2) Advantages Easier to manage than bus Handles high volume network better than bus Suited to transmitting signals over long distances Disadvantages Expensive equipment and wiring Fewer equipment options M. Dahshan - TCOM5272 13 Star Topology Multiple nodes attached to central device (hub, switch, router) Cable segments radiate from center like a star Example: workstations connected to switch M. Dahshan - TCOM5272 14 Star Topology (2) Advantages Easier to manage, defective nodes quickly isolated Easier to expand Better equipment and high-speed options Disadvantages Failure of central device may cause network failure Requires more cable than bus M. Dahshan - TCOM5272 15 Mesh Topology Every node connected to every other node in network Often used in MANs and WANs M. Dahshan - TCOM5272 16 Mesh Topology (2) Advantages Fault tolerance Alternate communication paths Disadvantages Expensive M. Dahshan - TCOM5272 17 M. Dahshan - TCOM5272 18 The ISO Reference Model Fundamental network communications model Product of two standards organizations International Organization for Standardization (ISO) American National Standards Institute (ANSI) OSI is theoretical, not specific hardware or software OSI guidelines analogized to a grammar M. Dahshan - TCOM5272 19 The ISO Reference Model (2) Accomplishments Enabling communications among LANs, MANs, WANs Standardizing network equipment Enabling backward compatibility to protect investments Enabling development of software and hardware with common interfaces M. Dahshan - TCOM5272 20 The ISO Reference Model (3) M. Dahshan - TCOM5272 21 Layered Model Reduces complexity Standardizes interfaces Facilitates modular engineering Ensures interoperable technology Accelerates evolution Simplifies teaching & learning M. Dahshan - TCOM5272 22 Physical Layer Transmit and receive signals Network connectors Signaling and encoding methods Detection of signaling errors Data transfer mediums wire cable fiber optics radio waves M. Dahshan - TCOM5272 23 Data Link Layer Format bits into frames Frame: discrete unit of information Contains control and address information Does not contain routing information Logical Link Control (LLC) Initiates communication between two nodes Media Access Control (MAC) Provides physical addressing Regulates access to the media M. Dahshan - TCOM5272 24 Network Layer Packet logical addressing Path determination Route optimization Addressing is done through routed protocols: IP, IPX, AppleTalk, DECnet Path Selection is done using routing protocols: RIP, IGRP, EIGRP, OSPF, BGP M. Dahshan - TCOM5272 25 Transport Layer Provides transparent flow of data End-to-end recovery Flow control and error control Data segmentation Ensures data received in order M. Dahshan - TCOM5272 26 Session Layer Manages dialog between applications Establishes, manages, terminates sessions Determines communication type Simplex Half-duplex Full-duplex M. Dahshan - TCOM5272 27 Presentation Layer Provides data representation and code formatting Translates between character codes Compression and encryption Example: Secure Sockets Layer (SSL) M. Dahshan - TCOM5272 28 Application Layer Provides network services to applications Remote access to printers Message handling for electronic mail Terminal emulation M. Dahshan - TCOM5272 29 Internet Standards Specifications of network technologies Ratified by the IETF Begins as Internet Draft (ID) Request For Comments (RFC) Not all RFCs are standards M. Dahshan - TCOM5272 30 Internet Standards (2) Examples of full standard RFCs RFC 791: Internet Protocol RFC 793: Transmission Control Protocol RFC 959: File Transfer Protocol Full List www.apps.ietf.org/rfc/stdlist.html M. Dahshan - TCOM5272 31 M. Dahshan - TCOM5272 32 Media Types Coaxial cable: copper wire Twisted-pair cable: copper wire Fiber-optic cable: glass or plastic Wireless: radio or microwaves M. Dahshan - TCOM5272 33 Coaxial Cables Used in bus topologies 10Base5 (thicknet, thickwire, RG8) 10Base2 (thinnet, thinwire) M. Dahshan - TCOM5272 34 10Base5 Transmission rate of 10 Mbps Longest cable run 500 m Two transmission types Baseband: single channel Broadband: multiple nodes on multiple channels M. Dahshan - TCOM5272 35 10Base5 (2) Has relatively large 0.4-inch diameter Copper or copper-clad aluminum conductor at core Conductor surrounded by insulation Aluminum sleeve wrapped around insulation PVC or Teflon jacket covers aluminum sleeve M. Dahshan - TCOM5272 36 10Base5 (3) 10BASE5 vampire tap MAU transceiver Source: Wikimedia M. Dahshan - TCOM5272 37 10Base2 Maximum speed 10Mbps Wire up to 185 meters (almost 200) Used for baseband data transmission M. Dahshan - TCOM5272 38 10Base2 (2) Attached to bayonet connector (BNC) BNC connected to Tconnector Middle of T-connector attached to NIC Terminator may be attached to one end of Tconnector M. Dahshan - TCOM5272 39 Twisted Pair Cables Contains pairs of insulated copper wires Outer insulating jacket covers wires Communication specific properties Copper wires twisted to reduce EMI and RFI Length: up to 100 meters Transmission speed: up to 10 Gbps M. Dahshan - TCOM5272 40 Twisted Pair Cables (2) RJ-45 plug-in connector attaches cable to device Less expensive and more flexible than T-connectors M. Dahshan - TCOM5272 41 Twisted Pair Cables (3) Two Types Shielded (STP) Unshielded (UTP) M. Dahshan - TCOM5272 42 Shielded Twisted Pair (STP) Surrounded by braided or corrugated shielding Shield reduces interference (EMI, RFI) Interval of twists in each pair should differ Connectors, wall outlets should be shielded Have proper grounding Used in strong interference environment Expensive cable and equipment M. Dahshan - TCOM5272 43 Unshielded Twisted Pair (UTP) Consists of wire pairs within insulated outer covering No shield between wires and encasement Most frequently used network cable Reducing EMI and RFI Twist interior strands (like STP) Build media filter into network equipment M. Dahshan - TCOM5272 44 Unshielded Twisted Pair (UTP)(2) M. Dahshan - TCOM5272 45 Unshielded Twisted Pair (UTP)(3) Fewer points of failure Has no shield that can tear (up through Category 5e) Connectors and wall outlets do not need shielding Proper grounding not as critical to purity of signal M. Dahshan - TCOM5272 46 Fiber-Optic Cables Glass or plastic fiber cores encased in glass tube (cladding) Fiber cores and cladding are surrounded by PVC cover Signal transmissions consist light (usually infrared) M. Dahshan - TCOM5272 47 Fiber-Optic Cables (2) Advantages Transmission speeds from 100 Mbps to over 100 Gbps No EMI or RFI problems Data travels by light pulse Low attenuation Secure from unauthorized taps M. Dahshan - TCOM5272 48 Fiber-Optic Cables (3) Disadvantages Fragile Expensive Requires specialized training to install Cannot be used for analog communications M. Dahshan - TCOM5272 49 Fiber-Optic Cables (4) Single-mode Used for long-distance communication 8-10/125 µm cable transmits one wave at a time Communications signal is laser light Multimode Supports multiple waves (broadband) Comes in two varieties step index graded index Cable diameter between 50 and 115 microns Source for multimode cable is LED M. Dahshan - TCOM5272 50 Fiber-Optic Cables (5) Connector types Subscriber Connector (SC) Straight Tip (ST) And others… Source: Wikimedia M. Dahshan - TCOM5272 51 M. Dahshan - TCOM5272 52 Activity 1-6: Viewing Network Links in Windows Time Required : 5–10 minutes Objective: View the Windows Server 2003 and Windows XP LAN and WAN connection options. Description: View the logical links between various types of networks— including dial-up and VPNs—joined through Windows Server 2003 and Windows XP Professional. M. Dahshan - TCOM5272 53 Activity 1-7: Determining Network Connectivity in UNIX/Linux Time Required: 5 minutes Objective: Viewing LAN and WAN connectivity in UNIX/Linux. Description: View network connectivity in Fedora or Red Hat Enterprise Linux, which is already configured with the X Window GNOME interface. M. Dahshan - TCOM5272 54 Activity 2-3: Viewing a NIC’s Physical Address Time Required: 5–10 minutes Objective: Determine the physical address of the NIC in a computer. Description: Provides an opportunity to determine the physical address of a network interface card (NIC) in a computer. You need access to a computer that is connected to a network and that runs Windows XP, Windows Server 2003, Fedora, or Red Hat Enterprise Linux. For Fedora or Red Hat Enterprise Linux, you need to use the root account. M. Dahshan - TCOM5272 55 Activity 2-6: Viewing Network Objects Using the Windows Redirector Time Required: 5–10 minutes Objective: Use the Microsoft Windows redirector. Description: The Microsoft Windows redirector is one example of the Application layer (Layer 7) at work. In this activity, you view computers, shared folders, and shared printers through a Microsoft-based network, which are made accessible, in part, through the redirector. Your network needs to have at least one workgroup (or domain) of computers, shared folders, and shared printers to fully view the work of the redirector. M. Dahshan - TCOM5272 56 Activity 4-1: Comparing Different Cable Types Time Required: Approximately 10 minutes Objective: Compare coax, twisted-pair, and fiberoptic cable. Description: You will better understand your network if you understand the physical differences among cable types. You will also be better able to design a new network or upgrade a legacy network. In this activity, you compare the flexibility and appearance of coaxial, twisted-pair, and fiber-optic cable. M. Dahshan - TCOM5272 57 Activity 4-2: Comparing Cable Connectors Time Required: Approximately 10 minutes Objective: Compare connectors for different cable types. Description: Each type of cable uses different kinds of connectors. This activity enables you to see the kinds of connectors used for different cable mediums. M. Dahshan - TCOM5272 58 Activity 4-4: Building a UTP Cable Time Required: Approximately 20–30 minutes Objective: Experience building a UTP cable. Description: In this activity, you attach 4pair UTP cable to an RJ-45 connector. You need the cable, a crimper, a connector, and a wire stripper. These instructions and Figure 4-6 follow the EIA/TIA-568-B standard. M. Dahshan - TCOM5272 59 M. Dahshan - TCOM5272 60 Homework Activities Chapter 1: 1-8 Chapter 2: 2-1 Problems Chapter 2: 1,2,4,8,9,11,14,15,16,17 Chapter 4: 1,2,6,8,9,10,11,12,13,14,15,16,18,20 M. Dahshan - TCOM5272 61