Operating Systems: Linux, UNIX, LAN Server, and Windows 2000

Linux

• Linux is a clone of the UNIX operating system that runs on multiple platforms.
• What makes Linux different is that it is a free implementation of UNIX.
• In Linux, you can run most popular software for UNIX, including the X Window System.
• Linux provides a complete software implementation of TCP/IP.
• Linux supports virtual consoles (VC).

UNIX

• UNIX is widely used in scientific research, and its application in other environments has been broadly accepted.
• Version SVR4 (System V Release 4) is the latest version of UNIX from AT&T.
• The original design philosophy was to divide UNIX functionality into small parts: the programs.
• In general, on UNIX machines, commands are not physically implemented on the computer you are typing on, but on the one to which you are connected.
• A UNIX computer usually offers a range of network services through programs that run continuously, called daemons.

LAN Server

• LAN Server is the network operating system based on OS/2 from IBM.
• LAN Server file servers are grouped by domains.
• LAN Server provides improved functions to access databases.
• LAN Server is preferred over other network operating systems (NOS) for customers who have invested heavily in mainframe computers.
• Access to resources can be made through their nicknames or aliases.

Windows 2000

Windows 2000 is based on NT technology. Regarding speed, Microsoft states that Windows 2000 Professional (on a computer with 64 MB RAM) exceeds Windows 95 by 39%, Windows 98 by 30%, and Windows NT Workstation by 24%.

Among the new or greatly improved services, note the following:

• Active Directory: Centralizes user resource information and facilitates administration.
• Communication Services: Networks with support for VPN protocols, ATM, DNS, DHCP, and TCP/IP.
• Printing Services: Significant improvements in management.
• Internet Information Server: New version with significant improvements in resource management.
• Multimedia Services: Integrated to distribute voice and video over the network.

Its real strength lies in having incorporated all users (and, especially, developers) from Windows 95/98 into NT technology.

Windows 2000 Editions

• Professional: Operating system for business computers, laptops, and desktops. Designed for internet users.
• Server: The multipurpose network operating system, ideal for workgroups and small business environments, allowing companies to adapt to the internet safely and affordably.
• Advanced Server: Edition designed for business applications and electronic commerce. It includes everything in Windows 2000 Server, plus availability and scalability features that support greater volumes of users and complex applications.
• Data Center Server: Designed for critical applications with high resource consumption, such as data warehouses or Application Server Providers.

Windows 2000 is a product designed for the enterprise.