Intergraph WebScale User Manual page 78

WebScale™ User's Guide
WebScale cluster communicates over the LAN connecting the cluster's hosts.
WebScale currently supports FDDI, Ethernet and fast Ethernet adapter cards. This term
is used interchangeably with adapter card.
Port rule
A set of configuration parameters supplied to the WebScale Setup dialog which
determine the filtering mode to be applied to a range of ports.
Scalability
Scalability is a measure of how well a computer system can grow to meet increasing
performance demands. These increased demands on server applications, such as web
servers, are often the result of both increased usage (that is, more requests from clients)
and growing complexity. Clustering two or more computers together is an efficient and
effective means for enhancing scalability by sharing the added load among the clustered
computers.
Server
A server is a computer used to serve requests from remote, client computers over local
and wide area networks. It typically runs a set of software applications, such as a web
server and FTP server, which use standard networking protocols, such as TCP/IP, to
communicate with clients. WebScale clusters TCP/IP servers to deliver high
availability and scalable performance for the server applications. This term is used
interchangeably with host in this documentation.
Session
In the context of load balancing TCP/IP traffic, a session is defined as a set of client
requests directed to a server. These requests may be invoked with multiple, possibly
simultaneous TCP connections, and the server application sometimes maintains state
information (such as, "server cookies") between requests. To preserve access to server
state, WebScale needs to direct all requests within a session to the same cluster host
when load balancing.
TCP/IP Protocol
TCP/IP ("Transmission Control Protocol/Internet Protocol") is the standard networking
protocol used over the Internet. WebScale clusters Windows NT servers and
applications that use TCP/IP. (It currently does not support other networking protocols,
such as IPX/SPX used on Novell networks.)
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