Network Structure Elements of communication message source the channel message destination Network data or information networks capable of carrying many different types of communications

Network Structure End Devices and their Role in the Network – End devices form the interface between the human network and the underlying communications network Examples: Computers, network printers, VoIP phones, security cameras, mobile handheld devices, etc.) – Role of end devices: client, server or both

Network Structure Intermediary Devices and their Role in the Network – Provides connectivity and ensures data flows across the network Network Access Devices (Hubs, Switches, APs) Internetworking Devices (Routers) Communication Servers and Modems Security Devices (Firewalls) – The management of data as it flows through the network. – Determine the path that messages should take through the network: Regenerate and retransmit data signals Maintain information about what pathways exist through the network and internetwork Notify other devices of errors and communication failures Direct data along alternate pathways when there is a link failure Classify and direct messages according to QoS priorities Permit or deny the flow of data, based on security settings

Network Types Local Area Networks (LANs) - An individual network usually spans a single geographical area (home, building or campus). - Provides services and applications to people within a common organizational structure (small business, campus, region) - Is usually administered by a single organization.

Network Types Wide Area Networks (WANs) - LANs separated by geographic distance are connected by a network known as a Wide Area Network (WAN) - Individual organizations usually lease connections through a telecommunications service provider (TSP) network. - Although the organization maintains all of the policies and administration of the LANs at both ends of the connection, the policies within the communications service provider network are controlled by the TSP.

Network Types The Internet is defined as a global mesh of interconnected networks (internetworks). The Internet is created by the interconnection of networks belonging to Internet Service Providers (ISPs) to provide access for millions of users all over the world. The Intranet is a private connection of LANs and WANs that belongs to an organization, and is designed to be accessible only by the organization's members, employees, or others with authorization.

Layers with TCP/IP and OSI Model TCP/IP Model

Layers with TCP/IP and OSI Model Compare OSI and TCP/IP model

IP Addressing Structure Each device on a network must be uniquely defined. At the Network layer, the packets of the communication need to be identified with the source and destination addresses of the two end systems With IPv4, this means that each packet has a 32-bit source address and a 32-bit destination address in the Layer 3 header.

Network Architecture Characteristics Four characteristics that are addressed by network architecture design – Fault tolerance – Scalability – Quality of service – Security

Computer Terminologies CPU - Central Processing Unit RAM - Random Access Memory ROM - Read-Only Memory CD-ROM drive Floppy disk drive Hard disk drive Bus System unit Motherboard (Mainboard) Expansion slot Network Card Video Card Sound Card Parallel port and Serial port 12

NIC: Network Interface Card 13

Select a NIC Type of Network: Ethernet, Token Ring, FDDI Type of media: Twisted-pair, Coaxial, Fiber-optic cable Type of system bus: PCI, ISA 14

Web browser 15

Internet Connectivity Computers connect to the internet in a number of ways, can you list them? Dial-up (Modem) ISDN DSL Cable Network

PC Basics (Components) Electronic components Transistor Integrated Circuit (IC) Resistor Capacitor Connector Light Emitting Diode (LED)

PC Motherboard Components Backplane Memory Chip Network Interface Card (NIC) Video Card Sound Card Parallel Port Serial Port Mouse Port Keyboard Port Power Cord Universal Serial Bus (USB) Port

TCP/IP Testing Ping A protocol used to test TCP/IP Connectivity Stands for Packet Internet Groper Sends multiple IP packets to destination computer (typically 4 -packets) Will receive the same number of replies Information obtained will allow you to ascertain network connectivity

IPConfig Used to verify current IP configuration Lab 1.1.6

Tracert Traces the route traffic takes from source to destination Lab 1.1.7

Good luck in the test!