CHAPTER Introduction to LANs MODULE Purpose and Use

CHAPTER Introduction to LANs

MODULE Purpose and Use of a Network

Definition of a Network • Composed of computing and information devices connected together – – – clients servers shared printers other shared devices internetworking devices • link to the external world – Etc.

Purpose • Access and share local resources and information – Hard and soft resources • Access and share global resources and information – Internet resources • Messaging, Collaboration etc.

A Note on Sharing and Collaboration • Sharing – One shares the application – The other watches the changes being made • Collaboration – Both share the applications and both can make the changes

Network Types • Locally oriented (LAN) • Globally oriented (WAN) • A combination of the above two types

A Simple Network Printer Client Server Client Peripheral Device (Modem) Directly attached peripheral (Network Printer)

Appliances • Network appliance – Network Attached Storage (NAS) – Network Printer • Internet appliance

NAS • NAS can be directly attached to network (switch, for example) • NAS components – Processor – Embedded OS (Eg: Embedded Linux) – Embedded software (Eg: SAMBA Server)

Sample Components of a Simple Network • Network Hardware • Network Software • Resources – Hard resources – Soft resources • Personnel – Administrators – Users

Hardware • Servers • Clients • Peripheral devices – Network printers – NAS • Media (Cabling) – Twisted pair, coaxial cable, optical fiber etc. – Wireless networks without cables • Networking Devices – Hubs, switches, routers

Media • CAT 5 – 100 Mbps LANs • CAT 5 e – 1000 Mbps LANs • CAT 6

Internetworking Devices • Hub – Simply shares the electrical connection • Switch – Switches the data packet based on MAC address • Bridge • Router – Routes the data packet based on the IP address

Software • Network operating system – Windows 2003 Server, Windows Server 2000, Linux etc. • Client operating system – Windows XP, Windows 2000, Linux etc. • Various application server operating systems – SQL server, Web server, FTP server etc.

Resources • Hard resources – Printers, scanners etc. • Soft resources – Folder, application etc.

Hard Resource Sharing Example Printer (Attached directly or to the Server) Print Queue Print Jobs Print Server

Soft Resource Sharing (File Server) Example Administrator User Server Tariff Resource (Folder to be shared). Client User

Application Server Example Database Administrator Sharing of SQL engine based application. Server with SQL engine and database. User Client User

Messaging Example Remote Client Internet E-mail Internet Gateway Messaging Server Administrator Client E-mail User

Personnel – Administrators • Administrator, account operator, server backup operators etc. – Users • Local user, power user, global user etc.

Network Administrator's Responsibilities • Install, manage and fine-tune the network resources • Create and manage users • Assign privileges to users to use the resources – Sharing resources – Accessing network applications • Ensure LAN security

Users • • • Global users Local users Group of users Power users Users with administrative privileges

Earlier Windows Servers • Windows NT – Windows NT Workstation, Windows NT Server, Windows NT Enterprise Server • Windows 2000 – Windows 2000 Professional – Windows 2000 Server – Windows 2000 Advanced Server – Windows 2000 Data Center Server

Windows 2003 Server Versions • • Web Edition Standard Edition Enterprise Edition Datacenter Edition

Network (Services) Servers • • • DHCP (Services) Server DNS (Services) Server Proxy (Services) Sever WINs (Services) server RAS (Services) Server – Routing and Remote Access Server • VPN (Services) Server • Share Point services

Application Servers • SQL Server • Web (Service) Server • Media (Service) Server

Major Network Architectures • . Net • J 2 EE

Web Research Areas • Directly attached network peripherals – Network printer, Network stand-alone hard drives (Snap) – Network appliance and a web appliance • Variations of the Windows Server 2003 operating system • What is the. Net architecture ?

Key Words • Hard and soft resources • Client operating systems – Windows 9 x, Windows NT, Windows 2000 Professional, Windows XP, Linux, OS/2, Mac OS X • Server operating systems – Windows NT Server, Windows 2000 Server, Windows 2003, Novell Net. Ware, Unix, Linux, OS/2 Warp

Further Keywords • Sharing of printers – local printer – shared printer – network printer • Symmetric Multi Processing (SMP) • Clustering – Load balancing

END OF MODULE

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