Avaya 38DHB0002UKDD - Manual (Page 140)

Page 140 Glossary
Glossary (Cont.)
Flash Completely delineated, flash is a solid-state, non-volatile, re-writable memory. Much like
RAM (Random Access Memory) flash uses memory cells to store electronic bits of data, but
flash differs from RAM in two respects. First, flash is non-volatile, unlike DRAM and SRAM
which must have constant power to retain data. Second, flash differs from RAM in the way
the read/write process works, since flash can only write data to a previously erased block of
memory. Some types of flash have a random-read feature like RAM, while others read data
sequentially, similar to a disk drive.
This combination of features makes flash well-suited both for file storage applications -
particularly portable or removable storage - and for XIP (eXecute In Place) and code-storage
applications.
FTP File Transfer Protocol (FTP). To download files from or upload files to remote computer
systems, via the Internet’s File Transfer Protocol. The user needs an FTP client to transfer
files to and from the remote system, which must have an FTP server. Generally, the user
also needs to establish an account on the remote system to FTP files, although many FTP
sites permit the use of anonymous FTP.
Gopher An Internet utility for finding textual information and presenting it to the user in the form of
hierarchical menus, from which the user selects submenus or files that can be downloaded
and displayed. One Gopher client may access all available Gopher servers, so the user
accesses a common “Gopherspace”. The name of the program is a three-way pun. It is
designed to go for desired information, it tunnels through the Internet and digs the
information up, and was developed at the University of Minnesota (whose athletic teams are
named the Golden Gophers). Gopher is being subsumed by the World Wide Web.
H.323 A standard approved by the International Telecommunication Union (ITU) that defines how
audiovisual conferencing data is transmitted across networks. H.323 should enable users to
participate in the same conference even though they are using different videoconferencing
applications.
HTTP Hypertext Transfer Protocol. The client/server protocol used to access information on the
World Wide Web.
HyperTerminal
Allows you to connect two computers with a modem so you can send and receive files, or
connect to computer bulletin boards and other information programs. For example, you can
use HyperTerminal to connect to an online service and to download files from a bulletin
board on that service. You can also use HyperTerminal to connect a computer directly to
another computer, such as a debugging terminal.
Internet Group Management Protocol (IGMP)
The standard for IP multicasting in the Internet. It is used to establish host memberships in
particular multicast groups on a single network. The mechanisms of the protocol allow a host
to inform its local router, using Host Membership Reports, that it wants to receive messages
addressed to a specific multicast group.
IP Header Compression (IPHC - RFC 2507 and RFC 2508)
IPHC reduces the IP/UDP/RTP headers to two bytes for most packets in the case where no
UDP checksums are being sent, or four bytes with checksums. IPHC therefore significantly
reduces WAN bandwidth requirements per voice call.
IP Office applies IPHC to all traffic types i.e. voice signalling/traffic and data. However, some
IP protocols yield a better compression ratio.
IPHC imposes process overheads which can become counter-productive at higher WAN
speeds. It is for this reason that IP Office will not perform IP Header compression at speeds
above 1024Kbps.
Page 140 - Glossary INDeX IPNC Cassette Administration Manual
38DHB0002UKDD – Issue 7 (22/11/02)