Network Concepts Communications Networks Need for Communications Networks Voice Communications Data Communications Transmitting Images Fax Video Analog and Digital Signals Types of Cabling Data Communications (Use bottom-up description) (Correlates to history of networking technology) (Increases with complexity of concepts) (Also correlates with OSI model and layers of abstraction) Physical Links and Interfaces (overview--details later in course) Client machines/user interfaces Computers w/ NICs Dumb terminals Service providers File servers Print servers Network printers Terminal servers Connection media Cabling--overview Cat3, Cat5 coax fiber Wireless IR Laser Radio/satellite Connecting hardware Routers Concentrators (hubs) Bridges Repeaters Protocols Fundamentals OSI/RM Physical link Link layer Network layer Routing services Transport layer Session layer Presentation layer Application layer Physical Layer protocols How bits are represented analog digital How to represent start/end of transmission Whether bits can move in one or both directions at once Link Level Transmission Procedures Link layer service connectionless vs. connection-oriented transmission accepts the address of a juxtaposed node to which it is passing data (physical link exists) accepts data packets of arbitrary length from network layer handshakes with peer to ensure complete frame reception reception participates in handshaking passes data packets to above network layer required services divide packets into frames sequence information into frames error detection and correction codes into frames handshaking (control) information into frames flow control of frame transmission (rate) use physical layer services to send/receive frames check frames for errors; correct when required reconstruct packets from frames handle problems through handshaking Service comparisons LAN access methods CSMA/CD IEEE 802.5 Token Ring ethernet version II AppleTalk LocalTalk EtherTalk TokenTalk Network Layer Protocols Peer processes are always on adjacent nodes Network layer services Unified addressing scheme Circuit switched vs. Packet switched Differences between circuit/packet switching and connectionless/connection-oriented connections Network layer vs. OSI/RM TCP/IP services TCP IP UDP ICMP Novell NetWare IPX AppleTalk vs. the OSI/RM Datagram delivery protocol (DDP) Routing Address selection and resolution Subnetworked addressing Routing information protocol (RIP) RIP loop prevention open shortest path first (OSPF) ARP and RARP WAN routing protocols OSPF RIP EGP Novell Netware RIP/SAP NLSP AppleTalk RTMP ZIP Transport Layer Peers can be anywhere on the network (end-to-end) Transport layer services Addressing--which process on the node Connection management Flow control and buffering Resource utilization multiplexing parallelization Protocols ISO 8073 TCP Novell transport services SPX Novell NCP burst mode AppleTalk Transaction Protocol (ATP) Session Layer Session services establishment of session multiple sessions per single transport connection one session over multiple transport connections conducting dialogs tokens managing activities activities sync points ending session gracefully Common protocols ISO8327 TCP Novell'ss NetBIOS AppleTalk's ASP Presentation Layer Presentation services data representation EBCDIC (extended binary coded decimal interchange code) ANSII (american standard code for information interchange) ASN.1 (abstract syntax notation 1) data security unauthorized use, false identification stealing data (wiretapping) inserting or removing data into data stream data compression Common protocols Novell's NCP, SMB, AFP AppleTalk's AFP Application Layer Application services user applications email news file transfer application services (not direct to users, but to programs) virtual filestores NFS network drives chooser-appleshare High Performance LAN Protocols LAN performance shared vs. dedicated bandwidth Ethernet switching technology Token Ring switching ATM migration TCP/IP and the Internet Cabling Design criteria length limits UTP--100m, 2 devices per segment thinnet--185m, 30 devices per segment, min .5m thicknet--500m, 100 devices per segment, min 2.5m fiber--2km, 2 devices per segment Note: UTP and fiber are star wired--2 devices per segment is the implicit definition. Ethernet can handle 1024 devices over the whole network. These are the limits imposed on UTP and fiber cabling. catagories of cable Cat 1 = No performance criteria Cat 2 = Rated to 1 MHz (used for telephone wiring) Cat 3 = Rated to 16 MHz (used for Ethernet 10Base-T) Cat 4 = Rated to 20 MHz (used for Token-Ring, 10Base-T) Cat 5 = Rated to 100 MHz (used for 100Base-T, 10Base-T) EMI avoidance same as the cabling pathways standard, EIA-569, table 4.8-5. Minimum Separation Distance from Power Source at 480V or less <2kVA 2-5kVA >5kVA Unshielded power lines or electrical equipment in proximity to open or non-metal pathways 5 in. 12 in. 24 in. (12.7 cm) (30.5 cm) (61 cm) Unshielded power lines or electrical equipment in proximity to grounded metal conduit pathway 2.5 in. 6 in. 12 in. (6.4 cm) (15.2 cm) (30.5 cm) Power lines enclosed in a grounded metal conduit (or equivalent shielding) in proximity to grounded metal conduit pathway - 6 in. 12 in. - (15.2 cm) (30.5 cm) Transformers & electric motors <------- 40-in (1.02 m) -----> Fluorescent lighting <------- 12-in (30.5 cm) ----> Source: Integrated Building Distribution Network (IBDN) User Manual - Northern Telecom, doc # IBDN-UM-9105, 1991. AWG cat5 22-24 AWG Installation techniques twists-per-foot maintenance 2-22 twists per foot normal, cat 5 should have 12 minimum bend radius UTP 4x outside diameter multipair 10x outside diameter STP non-plenum 7.5cm STP plenum 15cm fiber, no tension 10 x outside diameter fiber, tension 20 x outside diameter fiber, all not less than 3cm dos and don'ts of Cat V Fiber optics LAN cabling design procedures determine end-user requirements identify a strategic plan for your organization evaluate the existing cabling system intermediate distribution frame (wiring closet) interframe backbone or riser sytems main distribution frame or computer room management systems local building code compliance moves, adds, changes Future trends asynchronous transfer mode (ATM) FDDI CDDI Intelligent wiring hubs Fast Ethernet vs. 100VGAnyLAN LAN Media Access Control (MAC) WAN Access Control Media Access Equipment: NICs, DCEs LANs LAN applications and uses Peer-to-peer LANs Client-server LANs Types and uses of servers print fax mail file web ftp other gopher archie whois X.500 finger authentication (kerberos, etc.) Ethernet (IEEE 802.3) Overview Operation and frame structure Ethernet options 10Base-T 10Base-2 10Base-5 10Base-FL FOIRL Ethernet components: repeaters tranceivers Traffic characteristics Strengths and weaknesses Token Ring (IEEE 802.5) Overview WANs WAN applications and uses Basic WAN services Switched 56Kbps ISDN FT-1, FT-3: applications, encoding, and fractional T-1 SONET OC-1 ATM Frame Relay X.25 SMDS DCE Equipment Modems CSUs/DSUs Multiplexing Inverse multiplexing Network Circuit Connectivity Internetworking Internetworking Devices Repeaters Bridges Routers Functional definition Switches Functional definition cut-through vs. store and forward hybrid designs Gateways LAN and WAN Equipment Routing Protocols Switching Overview Ethernet Token Ring FDDI ATM Interconnecting LANs Interconnecting WANs Network Software and Operating Systems Computer Operating Systems MS-DOS Windows 95, NT MacOS Unix Network Operating Systems (NOSs) Novell Netware Windows NT (, 95) Unix OS/2 AppleTalk TCP/IP Overview Stacked Protocols and Standards TCP/IP history Standards control RFCs, FYIs TCP/IP Stack Overview Layer responsibilities process layer FTP, TELNET, SMTP, DNS, RIP host-to-host layer TCP UDP internet layer IP, ARP, ICMP, EGP, OSPF network interface layer ethernet, Token Ring, SLIP, PPP Standard RFCs by layer Network Interface Layer Ethernet II headers packet information IEEE 802.3, 802.5, SLIP, PPP IP Networks, Subnets, and Hosts IP addressing IP communications logic process Subnetting IP networks applying the mask when to subnet Address Matching Hosts file DNS Address resolution protocol (ARP) Reverse address resolution protocol (RARP) Boot protocol (BOOTP) Internet Protocol The self-healing network Internet Control Message Protocol (ICMP) Telnet What telnet can do, when to use it File Transfer Protocol (FTP) What FTP is used for Commands Response codes Command/response sequnces in a live session Simple Mail Transfer Protocol (SMTP) Commands Response codes Multipurpose Internet Mail Extensions (MIME) SMTP futures Automated TCP/IP Configuration Reverse address resolution protocol (RARP) Boot protocol Dynamic host configuration protocol (DHCP) compared to BOOTP virtual IP networking TCP/IP Internet Services Uniform resource locators (URL) Archie Gopher World wide web home page Netscape Lynx Access methods PPP vs. SLIP dial-up direct Strengths and Weaknesses IPng (IPv6) Emerging Technologies Benefits and Applications ATM Iso - Ethernet 1Gbps Ethernet Fiber Channel Wireless Networks PC Repair Overview of System Features and Components Types of Systems PC-type machines Macintosh's Documentation System Teardown and Inspection Proper Tools and Test Equipment Disasembly Procedures Building a System from Scratch System Components Motherboard I/O ports Floppy disk drives Hard disk drives CD-ROM drives Power supply Expansion cards Motherboards Replacement motherboards ROM bios compatibility Bus Slots and I/O Cards What is a bus? Processor bus Memory bus Address bus Types of I/O buses System resources Interrupts (IRQs) DMA channels I/O port addresses Resolving resource conflicts Microprocessor Types and Specifications Processor specifications Data bus Internal registers Address bus Processor speed ratings Intel processors 386 486 Pentium Pentium Pro Overdrive processors and sockets PowerPC processors 601 603 603e 604 604e 750 (G3) Memory System logical memory layout Conventional (base) memory Upper memory area (UMA) Extended memory Expanded memory Physical memory Single in-line memory modules (SIMMs) Dual in-line memory modules (DIMMs) Memory banks Parity checking RAM chip speed EDO RAM Testing memory Power Supply Power supply troubleshooting Repairing the power supply Power-protection systems Input Devices Keyboard troubleshooting and repair Mouse troubleshooting Video Display Hardware Video adapter and display troubleshooting Communications and Networking Using communications ports and devices Serial ports Parallel ports Integrated services digital network (ISDN) Install and configure adapter cards Understanding the components of a LAN Audio Hardware Sound card installation and troubleshooting Floppy Disk Drives and Controllers Drive installation troubleshooting and repair Hard Disk Drives Hard disk drive operation Basic hard disk drive components Hard disk platters Logic boards Read/write heads Cables and connectors Hard Disk Interfaces The IDE interface Enhanced IDE (ATA-2) SCSI configuration and troubleshooting IDE vs. SCSI Disk hardware and software limitations Hard Disk Installation and Troubleshooting Installation procedures Formatting and software installation Low level format Drive partitioning Hard disk troubleshooting and repair CD-ROM Drives CD-ROM drive specifications Interfaces SCSI IDE Proprietary Loading mechanism Preventive Maintenance Active preventive maintenance procedures Hard disk maintenance Defragmenting files Backing up of filesystem Checking for virii Passive preventive maintenance procedures Software and Hardware Diagnostic Tools Diagnostic software Power-on self test (POST) General purpose diagnostics programs Disk diagnostics Data recovery utilities Configuration utilities Link Level Transmission Procedures Link layer service connectionless vs. connection-oriented Service comparisons LAN access methods CSMA/CD IEEE 802.5 Token Ring ethernet version II Novell frame formats addressing LABS 1: Build a classroom network--we will use 20 MacPlus's and an IBM PS/2 Model 30, in conjunction with a Tribestar Ethernet- LocalTalk bridge 2: Verify PC and Mac hardware and configuration--learn how to determine the component parts of the hardware and how to make the software make use of them 5: Configure TCP/IP networking on the lab machines--utilize a Class C network, employ proper subnetting, and correct static and default routing--troubleshoot using ping, traceroute 6: Create a file server--using AFP, FTP, SAMBA 7: Load a Novell Netware protocol stack--we will connect to the Blair Media Center Novell file server 26: Configure your TCP/IP computer to use DHCP to automatically configure the other computers in the lab 48: Configure and test secure messaging using PGP