Peer-to-Peer vs. Client/Server Network Operating Systems Instructor: Dr. Najla Al-Nabhan 2015
Peer-to-peer vs. server-based networks • A network is either: • a peer-to-peer network (also called a workgroup) or • a server-based network (also called a client/server network). Peer-to-peer based NW Client/Server based NW
Peer-to-peer networks • In a peer-to-peer network, a group of computers is connected together so that users can share resources and information. • In most peer-to-peer networks, it is difficult for users to track where information is located because data is generally stored on multiple computers. • This makes it difficult to back up critical business information, and it often results in small businesses not completing backups. • Often, there are multiple versions of the same file on different computers in the workgroup.
Peer-to-peer networks • In some peer-to-peer networks, the small business uses one computer that is running a client operating system, such as Microsoft Windows 98 or Windows XP Professional, as the designated "server" for the network. • Although this helps with saving data in a central location, it does not provide a robust solution for many of the needs of a small business, such as collaborating on documents.
Client/Server Networks • In a server-based network, the server is the central location where users share and access network resources . • This server controls the level of access that users have to shared resources. • Shared resources are in one location, making it easy to back up critical business information. • Each computer that connects to the network is called a client computer.
Client/Server Networks • In a server-based network, users have one user account and password to log on to the server and to access shared resources. • Server operating systems are designed to handle the load when multiple client computers access server-based resources.
Client/Server Networks • A Server OS is installed and configured as the central server on a server-based network mainly to provide: • the central point for authenticating users, • accessing resources, and • storing information.
Peer-to-peer NOS • Computers in peer-to-peer networks are usually equipped with a desktop operating system in order to allow them to create and share resources with each other. • All computers are considered equal because they have the same capabilities including : routing and management functions. • Two well-known NOS : • Windows for workgroup/windows 95 • Appleshre
Peer-to-peer NOS • The range of features offered by peer-to-peer NOS is limited when compared to server NOS. • They usually offer file sharing and printing as basic features • For small networks
Windows for Workgroups/Windows 95 • Windows for Workgroups, introduced in the early 90s • Windows 95, introduced in 1995 • They are both considered peer-to-peer networking systems and do not have the capabilities of true internetworking operating systems. • They are, however, inexpensive and more than adequate for small workgroups wanting to share resources, use email, and connect to the Internet.
Windows for Workgroups/Windows 95 • Windows for Workgroups and Windows 95 both offer peer-to-peer network protocols. • The protocols used by these operating systems allow users to share files and devices over LANs. • Both offer NetBEUI (Microsoft’s small network protocol). • They also offer TCP/IP, and IPX/SPX protocols to access the network through either a dialup connection/modem, or directly through a NIC.
NetBEUI features • Pronounced net-booey, NetBEUI is short for NetBios Extended User Interface. • It is an enhanced version of the NetBIOS protocol used by network operating systems such as: • LAN Manager, LAN Server, Windows for Workgroups, Windows 95 and Windows NT. • Netbeui was originally designed by IBM for their Lan Manager server and later extended by Microsoft and Novell.
NetBEUI features • NetBEUI protocols, are : • not routable, • more than adequate to meet small LAN needs. • easy to use and do not require in-depth networking knowledge. • NetBEUI software identifies computer devices by name it is easier to remember that a computer name is Nora than 126.96.36.199 or 188.8.131.52.
Windows for Workgroups/Windows 95 • Each device name in a network must be unique. • NetBEUI software installed on each of the networked computers is all that is necessary to configure devices in order to share resources and create a network. • If a small company does want to connect to the Internet, the necessary software and protocols are available with these operating systems. • Shared resources on Windows for Workgroups/95 networks are accessed by a password that protects the resource and there is only one level of access; either you have access or you don’t have access.
Windows for Workgroups/Windows 95: Security Issues • Also user-by-user passwords are not part of the protocols unless Windows NT is present. • What this means is that anyone connected to the network who knows the password of the resource has access to that resource. • This can create security issues since there is no way to prevent a user from access once s/he knows the password.
Windows for Workgroups/Windows 95:Security Issues • As the network grows, it is usually more difficult to keep resource passwords secure. • Since there is no central control, managing these peer-to-peer networks becomes an issue when the network becomes too large.
Windows for Workgroups/Windows 95:Security Issues • To be continued next lecture…