Let's Get Started
The unifying factor in the universal choice of TCP/IP is the Internet. The Internet has forced the computer industry and consumers of computer technology to conform to a common set of networking protocols. The lowest level protocols are common everywhere. These include Transmission Control Protocol (TCP), Internet Protocol (IP), Internet Control Message Protocol (ICMP), Address Resolution Protocol (ARP), and a number of other less well-known protocols. They are all so pervasive that interoperability with different implementations is no longer a major concern. Microsoft TCP/IP talks with Sun Microsystems TCP/IP talks with Apple TCP/IP. So, what is the big fuss about interoperability?
Internet protocols support the sending of messages and data streams between computer systems, similar to the way a telephone line supports sound between two handsets. Both computers and telephones share a similar problem. A telephone network transmits sound from one handset to another. However, it is not enough to simply have sound connectivity; the actual content must be mutually understood. A common language eliminates most of the communications issues for telephones. Still, it is possible for someone at one end of a telephone conversation to have no idea what the person at the other end is communicating.
In computer systems, the same problem arises. Once connectivity is established, higher level protocols must be used to communicate specific information. Examples of these protocols include:
Line Printer Daemon (lpd) protocol, used for printing to remote printers.
Network File System (NFS) protocol, used for sharing files over a network.
Common Internet File System (CIFS), used to share files, printers, authentication, and something called named pipes.
Simple Mail Transfer Protocol (SMTP), used to transfer mail between mail servers.
There are countless examples. In all cases, software at both ends of a TCP/IP connection is required to add meaning to the data transferred reliably over the connection. Higher level protocols are usually associated with a service that frequently goes by the same name. For example, lpd is a line printer protocol and lpd is a program running on Unix and Linux systems, which spools print jobs for a printer. NFS is both a protocol defined in an Internet Engineering Task Force (IETF) standard and a service that provides file sharing over a network. CIFS is similar to NFS in the services it provides, but included in its protocol are network line printer support, authentication, and named pipes. SMTP is the protocol used on the network "wire" and on the server that runs on Linux and Unix systems (called sendmail). Other vendors also implement the SMTP protocol but do not necessarily call their program SMTP or even sendmail.
We will see that both Windows 2000 and Linux can provide the same facilities. Using a fictitious firm, Elsolutions, we will examine many of the services that both Linux and Windows 2000 offer. Some will be set up on Linux, and some will be set up on Windows. Before we can identify useful services, we must describe our company.