Glossary of terms and abbreviations, Term definition – Wegener Communications 6420 User Manual
Page 24
iPump 6420 User’s Manual
www.wegener.com
800070-01 Rev B
Chapter 1, Page 20
1.6.
Glossary of Terms and Abbreviations
Term
Definition
AFD
Assured File Delivery, the WEGENER system for file downloads through
satellite channels
Alarm
An indication of a serious fault, generally expected to prevent the i6420
from fulfilling a basic mission
Application
Term used to describe the controlling software that runs on top of an Linux
Operating System, and that provides most i6420 functionality.
ASI
A physical interface for MPEG Transport streams, featuring bit-serial
transmission on a baseband signal with 270 MHz signaling rate. The data
is sent asynchronously, meaning the interface conveys a data byte when
available at the sender, and padding bytes otherwise.
Boot Loader
A small program that briefly runs on top of the Linux OS in the i6420 that
loads and runs the main application.
Carrier
An RF signal whose envelope and phase is modulated (manipulated) in an
defined fashion in order to convey information.
Client
A program that can be started and ran on a computer that seeks services
from server programs. Usually human operators will interface directly
with the client to seek these services.
Compel
WEGENER’s trademark Control system, optimized for control of media
distribution systems using edge devices such as WEGENER’s iPump 6420.
DVB
Digital Video Broadcast. Term used to represent the methods and
protocols using MPEG Transport streams to distribute media content over
satellite
Eb/No
In digital carrier systems, the energy per information-bit divided by the
channels noise density per Hertz. This is the key figure of merit for signal-
to-noise ratio.
Ethernet
The widely-used LAN technology specified by IEEE standard 802.3
FEC
Forward Error Correction. A transformation done on a stream or block of
information, expressed in bits, bytes, or frames, where some small amount
of redundancy is added. This is done in a manner such that, when the
transformed (FEC-encoded) stream of data is conveyed over error-prone
communication links, such as satellite channels, the errors can be removed
and the original information message recovered.
FTP
File Transfer Protocol. Industry-standard method for transferring files
between host computers over IP networks.
HTTP
Hypertext Transfer Protocol. This is the protocol supported by web
servers and clients. It actually describes a set of methods to upload and
download, not only web pages, but any kind of file. The i6420 uses the
HTTP POST method to upload files to remote servers, and uses the GET
method to download files from remote servers.
IP
Internet Protocol. The internetworking protocol that allows host
computers to communicated over local networks or over the internet.
IRD
Integrated Receiver-Decoder. A product which features a "receiver" to extract
Transport streams from satellite-borne carriers & a companion "decoder" to
decompress MPEG elementary streams (from within said transport streams) in
order to recreate the original audio/video/data signals. The WEGENER Unity 4600
is an IRD.