Extron electronics SMP 300 Series User Manual page 172

DDC — Display Data Channel (DDC) is a bidirectional communications standard
developed by VESA (Video Electronics Standards Association) that defines a universal data
transmission standard for the connectivity between display devices and computers.
Decoder — 1) In analog video, a device used to separate the RGBS (red, green, blue and
sync) signals from a composite video signal. Also known as an NTSC decoder. 2) In digital
systems, a device which does the reverse of an encoder, undoing the encoding so that
the original information can be retrieved. The same method used to encode is usually just
reversed in order to decode. Video over IP decoders accept IP data streams and output
an analog or digital video signal. 3) In control systems, the device in a synchronizer or
programmer which reads the encoded signal and turns it into a form of control.
Dynamic Host Configuration Protocol (DHCP) — A network protocol that enables
a server to automatically assign unique network addresses (IP address, subnet mask,
gateway) to a device using a defined range of numbers configured for the network.
DiffServe (Differentiated Services) — DiffServ specifies a scalable, coarse‑grained
mechanism for classifying and managing network traffic and providing quality of service
(QoS).
Domain Name System (DNS) — A database system that translates domain names
(such as www.extron.com) into IP addresses.
Dual channel encoding mode — The SMP 300 Series mode that signals from channel A
and signals from channel B are encoded to separate archive streams (and, therefore,
separate recordings), each with its own settings. SMP 352 Series models and SMP 351
Series models with LinkLicense offer both dual channel encoding and composite encoding.
Dual channel encoding, the alternative to composite encoding mode, signals from channels
A and B are combined into one archive stream (forming a single recording). All models offer
composite encoding mode.
Dynamic IP address — An IP address that is automatically assigned to a client device in
a TCP/IP network, typically by a DHCP server. Network devices that serve multiple users,
such as servers and printers, are usually assigned a static (unchanging) IP address.
Extended Display Identification Data (EDID) — A data structure used to communicate
video display information, including native resolution and vertical interval refresh rate
requirements, to a source device over the Display Device Channel (DDC). The source device
outputs the optimal video format for the display based on the provided EDID, ensuring
proper video image quality.
EDID Minder — Automatically manages EDID communication between connected devices.
Elementary Stream — Raw H.264 (MPEG-4 AVC) AAC
(see page 165) video or raw
audio (see page 162), not wrapped by additional headers.
Encoder — A hardware device or software program used to compress (encode) or change
a signal from one format to another or convert an analog signal into a digital data stream.
The SMP 300 Series is an encoder that converts analog audio and video into digital
streams.
Ethernet — A Local Area Network (LAN) standard officially known as IEEE 802.3. Ethernet
and LAN technology are used for interconnecting computers, printers, workstations,
terminals, services, and similar devices, within the same building or campus. Ethernet
operates over twisted pair and over coaxial cable at speeds starting at 10 Mbps. For LAN
interconnectivity, Ethernet is a physical link and data link protocol reflecting the two lowest
layers of the OSI Reference Model.
File Transfer Protocol (FTP) — A protocol that is used to transfer files from one host
to another host over a TCP‑based network (such as the Internet). Also see Secure File
Transport Protocol (SFTP) on page 167 for more information.
SMP 300 Series • Glossary 164