Hardware Reference
In-Depth Information
A dedicated server computer often has faster processors, more memory, and more storage
space than a client because it might have to service dozens or even hundreds of users at
the same time. High-performance servers typically use from two to eight processors (and
that's not counting multicore CPUs), have many gigabytes of memory installed, and have
oneormoreserver-optimizednetworkinterfacecards(NICs),RAID(RedundantArrayof
Independent Drives) storage consisting of multiple drives, and redundant power supplies.
Servers often run a special network OS—such as Windows Server, Linux, or UNIX—that
is designed solely to facilitate the sharing of its resources. These resources can reside on
a single server or on a group of servers. When more than one server is used, each server
can “specialize” in a particular task (file server, print server, fax server, email server, and
so on) or provide redundancy (duplicate servers) in case of server failure. For demanding
computing tasks, several servers can act as a single unit through the use of parallel pro-
cessing.
A client computer typically communicates only with servers, not with other clients. A cli-
ent system is a standard PC that is running an OS such as Windows. Current OSs contain
clientsoftwarethatenablestheclientcomputerstoaccesstheresourcesthatserversshare.
Older OSs, such as Windows 3.x and DOS, required add-on network client software to
join a network.
