Chapter One An Introduction to Networking Welcome to Networking and Telecommunications Professor: Ken Clifton, CISSP, MCSE, MCSD, MCDBA, Network+, A+, CTT+, CXE

Networks and Standalone Computers Network Group of computers and other devices connected by some type of transmission media Group of computers and other devices connected by some type of transmission media Networks enable users to share devices and data, collectively called a network’s resources Networks enable users to share devices and data, collectively called a network’s resources Standalone computer Uses programs and data only from its local disks and is not connected to a network Uses programs and data only from its local disks and is not connected to a network

Sneakernet Method of sharing data by copying it to a disk and carrying the disk from computer to computer Figure 1-1: Data sharing before the advent of networks

Local and Remote Computers Local computer Computer on which user is working Computer on which user is working Remote computer Computer that user controls or works on via network connection Computer that user controls or works on via network connection

Peer-to-Peer Network Computers communicate on single segment of cable and share each other’s data and devices Simple example of a local area network (LAN) Figure 1-2: Simple peer-to-peer network

Local Area Network (LAN) Network of computers and other devices confined to relatively small space LANs involving many computers are usually server-based On a server-based network, special computers (known as servers ) process data for and facilitate communication between other computers on the network (known as clients ) On a server-based network, special computers (known as servers ) process data for and facilitate communication between other computers on the network (known as clients )

Networking Basics Workstation Computer that typically runs a desktop operating system and connects to a network Computer that typically runs a desktop operating system and connects to a network Client/server architecture Networking model in which clients use central server to share applications, devices, and data Networking model in which clients use central server to share applications, devices, and data The most common network architecture The most common network architecture

Networking Basics Client/server network Network based on client/server architecture Network based on client/server architecture Network operating system Special software designed to manage data and other resources on a server for a number of clients. Special software designed to manage data and other resources on a server for a number of clients. Be prepared to identify examples of NOS(s) Be prepared to identify examples of NOS(s)

Networking Basics Figure 1-3: LAN with a file server

Networking Basics Figure 1-4: An example of a complex network

Advantages of Server-Based over Peer-to-Peer Networks User login accounts and passwords can be assigned in one place Access to multiple shared resources can be centrally granted Servers are optimized to handle heavy processing loads and dedicated to handling requests from clients Servers can connect more than a handful of computers

MANs and WANs Metropolitan area network (MAN) Network connecting clients and servers in multiple buildings within limited geographic area Network connecting clients and servers in multiple buildings within limited geographic area Wide area network (WAN) Network that spans large distance and connects two or more LANs Network that spans large distance and connects two or more LANs The Internet is an example of a very intricate and extensive WAN that spans the globe The Internet is an example of a very intricate and extensive WAN that spans the globe

WAN Figure 1-5: A simple WAN

Elements Common to All Server-Based Networks Client In addition to referring to a computer on the network, may also refers to human user of client workstation In addition to referring to a computer on the network, may also refers to human user of client workstation Server – what differentiates a server? Workstation Network interface card (NIC) Enables workstation to connect to the network and communicate with other computers Enables workstation to connect to the network and communicate with other computers

Elements Common to All Server-Based Networks Figure 1-6: A network interface card (NIC)

Network operating system (NOS) Be able to identify examples of NOS. Be able to identify examples of NOS.Host Server that manages shared resources Server that manages shared resourcesNode Client, server, or other device that can communicate over a network and that is identified by a unique identifying number, known as its network address Client, server, or other device that can communicate over a network and that is identified by a unique identifying number, known as its network address Elements Common to All Server-Based Networks

Topology Physical layout of computer network Physical layout of computer network Figure 1-7: Commonly used network topologies

Elements Common to All Server-Based Networks Protocol Rules network uses to transfer data Rules network uses to transfer data Data Packets The distinct units of data transmitted from one computer to another on a network The distinct units of data transmitted from one computer to another on a network

Elements Common to All Server-Based Networks Addressing Scheme for assigning unique identifying number to every workstation on network Scheme for assigning unique identifying number to every workstation on network The number that uniquely identifies each workstation and device on a network is its address The number that uniquely identifies each workstation and device on a network is its address

Elements Common to All Server-Based Networks Transmission media Means through which data are transmitted and received Means through which data are transmitted and received Figure 1-8: Examples of network transmission media

How Networks Are Used Services Features provided by a network Features provided by a network File and print services Application services (not in text) Communications services Mail services Internet services Management services

Network Services File services Refers to capability of a server to share data files, applications, and disk storage space Refers to capability of a server to share data files, applications, and disk storage space Server that provides file services is called a file server Server that provides file services is called a file server Print services Allows printers to be shared by several users on a network Allows printers to be shared by several users on a network

Network Services Application services Database servers, voice mail, terminal services, etc. Database servers, voice mail, terminal services, etc. Actually running a program. Actually running a program. Communications services Allow remote users to connect to a network Allow remote users to connect to a network Remote user Person working on a computer in a different geographical location from the LAN’s server Person working on a computer in a different geographical location from the LAN’s server Communications server Communications server Server that runs communications services Also referred to as access servers and remote access servers

Network Services Mail services Coordinate storage and transfer of between users on a network Coordinate storage and transfer of between users on a network Gateway services Combination of software and hardware enabling two different kinds of networks to exchange data Combination of software and hardware enabling two different kinds of networks to exchange data Internet services Enable networks to communicate with the Internet Enable networks to communicate with the Internet

Network Services Management services Centrally administer and simplify complicated management tasks on the network Centrally administer and simplify complicated management tasks on the network Numerous services fall under category of network management Numerous services fall under category of network management

Important Management Services Traffic monitoring and control Traffic Traffic Data transmission and processing activity taking place on a computer network at any given time Segment Segment Part of LAN that is logically separated from other parts of LAN and that shares fixed amount of traffic capacity

Important Management Services Load balancing (aka. Clustering) Distributing process activity evenly across a network so that no single device is overwhelmed Distributing process activity evenly across a network so that no single device is overwhelmed Hardware diagnosis and failure alert Determining when a network component fails and automatically notifying network administrators through or pager Determining when a network component fails and automatically notifying network administrators through or pager

Important Management Services Asset management Collecting and storing data on number and types of software and hardware assets in an organization’s network Collecting and storing data on number and types of software and hardware assets in an organization’s network License tracking Determining how many copies of a single application are currently in use on a network Determining how many copies of a single application are currently in use on a network

Important Management Services Security auditing Evaluating what security measures are currently in force and notifying network administrator if a security breach occurs Evaluating what security measures are currently in force and notifying network administrator if a security breach occurs Software distribution Automatically transferring data file or program from the server to a client on the network Automatically transferring data file or program from the server to a client on the network

Important Management Services Address management Centrally administering a finite number of network addresses for an entire LAN Centrally administering a finite number of network addresses for an entire LAN Backup and restoration of data Backing up Backing up Copying critical files to a secure storage area Restoring Restoring Retrieving data if original files are lost or deleted

Mastering the Technical Challenges Specialty areas in high demand for networking professionals: Network security Network security Internet and intranet design Internet and intranet design Network management Network management Voice/data integration Voice/data integration * Consider what is easiest to outsource in this environment (programming or networking)?

Mastering the Technical Challenges Specialty areas in high demand for networking professionals (cont.): Data integrity and fault tolerance Data integrity and fault tolerance In-depth knowledge of Microsoft networking products In-depth knowledge of Microsoft networking products In-depth knowledge of NetWare networking products In-depth knowledge of NetWare networking products In-depth knowledge of router configuration and management In-depth knowledge of router configuration and management

Pursuing Certification Certification Process of mastering material pertaining to a particular hardware system, operating system, programming language, or other software program, then proving your mastery by passing a series of exams Process of mastering material pertaining to a particular hardware system, operating system, programming language, or other software program, then proving your mastery by passing a series of exams Computer Technology Association (CompTIA) An association that sets industry-wide standards for computer professionals An association that sets industry-wide standards for computer professionals

Pursuing Certification A+ Certification established by CompTIA Certification established by CompTIA Verifies knowledge about PC operation, repair, and management Verifies knowledge about PC operation, repair, and management Microsoft Certified Systems Engineer (MCSE) Certification established by Microsoft Certification established by Microsoft Demonstrates in-depth knowledge about Microsoft’s products Demonstrates in-depth knowledge about Microsoft’s products Current Counts: Current Counts:

Pursuing Certification Certified NetWare Engineer (CNE) Certification established by Novell Certification established by Novell Demonstrates in-depth understanding of Novell’s networking software Demonstrates in-depth understanding of Novell’s networking software Network+ (Net+) Certification established by CompTIA Certification established by CompTIA Verifies broad, vendor-independent networking technology skills Verifies broad, vendor-independent networking technology skills CCNA and CCIE Cisco Certification CISSP – ISC2 International Information Systems Security Consortium

Pursuing Certification Benefits of becoming certified include: Better salary Better salary Greater opportunities Greater opportunities Professional respect Professional respect Access to better support Access to better support

Chapter Summary A Network is a group of computers or other devices connected by some type of transmission media Networks may be small or large, connecting computers in one office or across the world All networks offer advantages relative to the use of standalone computers Simplest form of a network still used today connects a handful of computers through one cable and uses peer-to-peer communication

Chapter Summary A LAN is a network of computers and other devices confined to a relatively small space A WAN is a network connecting two or more geographically distinct LANs All server-based networks share some common elements The physical layout of a computer network is called a topology Network protocols are rules the network uses to transfer data

Chapter Summary File and print services provide foundation for networking Communications services allow remote users to connect to the network Mail services allow networks users to exchange and store Internet services enable organizations to connect to the Internet Network management services centrally administer and simplify complicated management tasks on network