Microsoft Internet Security and Acceleration Server 2000

H

H.323 Protocol
The International Telecommunications Union - Telecommunications (ITU-T) standard protocol for real-time multimedia communications and conferencing over packet-based networks.
hash
A mathematical algorithm used for routing client requests within an array or a chain. The result of the hash determines which specific ISA computer to send the client request.
header
In data packet communications, a specified number of bytes that precedes the actual data being transmitted. It identifies control information used to deliver, route, and process the data contents of a packet.
hierarchical caching
The forwarding of a client HTTP request from one ISA computer to another ISA computer upstream. The downstream (source) ISA computer forwards client requests that it cannot service from its own cache. Hierarchical caching uses upstream routing and is a subset of distributed caching.
hierarchical chaining
Linking multiple ISA computers together to form a chain. Individual ISA computers, arrays, or any combination can be chained.
hit rate
The percentage of client requests fulfilled through previously cached data, in contrast to the total of all client requests that have been processed by the caching service.
home directory
See root directory.
host name
The name given to a computer that is part of a Windows 2000 network domain and used for client authentication. Also called the computer name. See also fully qualified domain name (FQDN).
HOSTS file
See LMHOSTS file.
HTML
Hypertext Markup Language (HTML). A markup language derived from the Standard Generalized Markup Language (SGML). Used to create a text document with formatting specifications that tells a software browser how to display the page or pages included in the document.
HTTP
The client/server protocol used to access information on the Web.
HTTP Redirector filter
A Hypertext Transfer Protocol (HTTP) redirector filter provided with ISA, that forwards HTTP requests from Firewall and secure network address translation (SecureNAT) clients to the Web proxy service.