--- title: Glossary - Common Terms & Acronyms slug: zen-master/glossary-common-terms-and-acronyms docTags: createdAt: 2025-04-16T17:39:08.248Z --- ## Zixi-Specific Terms - **Content Analysis: **Zixi Broadcaster includes analysis of video content in addition to existing transport and network analysis. Including: - **Audio clipping detection** - Detects clipped audio upon occurrence on AAC or MPEG audio. - **Audio levels** – Detects audio volume level for every channel on AAC or MPEG audio. The analysis of the various audio tracks is available in the audio tree. The volume is presented in dBFS (Decibels relative to full scale). - **Audio silence detection **(AAC/MPEG audio) – Detects silence (dBFS\< -90) on AAC or MPEG audio with a duration of about 30s or longer. - **Blank video detection** - Detects blank frames of any color for a duration of about 60s or longer. - **Frozen video detection **- Detects frozen video, i.e. no motion, for a duration of about 60s or longer. - **I-Frame Quantization Parameter** – This indicator detects cases where the source encoder configuration is creating excessively lossy content. The analysis does not rely on the bitrate, but rather extracts the global quantization parameter, which is a parameter that indicates how much information was lost during encoding, from the elementary stream. - **FEC (Forward Error Correction)**: A method of error correction that adds redundant data to help recover lost packets without needing retransmission. - **FEC Block Latency: **The FEC Block Latency (ms) parameter sets the number of milliseconds that Zixi protects with a single FEC block. - **Hitless Failover**: A feature in Zixi that allows seamless switching between redundant feeds for uninterrupted streaming without packet loss or viewer interruption. - **IFB (Interruptible Foldback Support): **IFB or switched talkback is a monitoring and cueing system for one-way communication allowing the decoder to send audio back to the encoder with a Zixi ZEC or Feeder. IFB support hast been implemented in Zixi Broadcaster Pull & UDP Outputs. - **Latency Mode**: Settings within Zixi that balance between ultra-low latency and resiliency, depending on network conditions. - **LOR (Loss Of Redundancy):** Loss of backup systems designed to ensure continuous playback and fault tolerance - **OnAir:** A Zixi app for remote contribution from mobile devices. - **ZaaS (Zixi-as-a-Service):** ZaaS is a cloud-based offering of Zixi’s platform in which Zixi provides and manages the Zixi Broadcasters, allowing the customer to focus entirely on managing content and distribution. - **ZEN: **Zixi Enabled Network - **ZEN Master: **ZEN Master is the live video orchestration and telemetry control plane that enables Zixi users to manage large-scale configuration and monitoring of the Zixi Enabled Network, Zixi’s live streaming platform, devices and appliances. - **Zixi Broadcaster**: A gateway server that can receive and redistribute streams to multiple endpoints, supporting protocol conversion, transcoding, and routing. - **Zixi Protocol**: A proprietary protocol developed by Zixi for reliable, low-latency, error-corrected transport of live video over IP networks. ## General Broadcasting & Streaming Terms ### Transport Protocols and Audio/Video Formats - **AAC (Advanced Audio Coding): **A widely used audio compression format that provides better sound quality than MP3 at similar bit rates. It's commonly used in streaming, digital music, and broadcasting. - **DASH (Dynamic Adaptive Streaming over HTTP): **An MPEG-standardized adaptive streaming protocol that delivers video over HTTP by dynamically switching bitrates based on network conditions, similar to HLS but codec-agnostic and not natively supported on Apple devices. - **H.264 (also known as Advanced Video Coding \[AVC]): **a widely used video compression standard designed to deliver high-quality video at lower bit rates. - **H.265 (also known as High Efficiency Video Codec \[HEVC]): **a video compression standard designed to improve efficiency over its predecessor, H.264 (AVC). It offers 25% to 50% better compression while maintaining the same level of video quality, making it ideal for streaming, broadcasting, and high-resolution video formats like 4K and 8K. - **HLS (HTTP Live Streaming): **An adaptive bitrate streaming protocol developed by Apple that delivers video over standard HTTP connections by breaking content into small chunks, enabling playback across a wide range of devices with high compatibility and higher latency. - **MP3 (MPEG-1 Audio Layer III): **A digital audio compression format that reduces file size while maintaining sound quality. - **MPEG-TS (Transport Stream)**: A standard container format for transmission and storage of audio, video, and data, widely used in broadcasting. - **RIST (Reliable Internet Stream Transport)**: An open standard streaming protocol built on UDP that adds features like error recovery, packet retransmission, and encryption to enable reliable, low-latency video transport over lossy or public IP networks. - **RTMP (Real-Time Messaging Protocol)**: A streaming protocol originally developed by Adobe for low-latency video, audio, and data transmission, commonly used to ingest live video streams into content delivery networks (CDNs). - **SRT (Secure Reliable Transport)**: An open-source transport protocol similar to Zixi, designed for low-latency, secure video delivery over IP. - **UDP (User Datagram Protocol): **A connectionless transport protocol that transmits data without error correction or retransmission, prioritizing speed and low latency, often used for live video streaming over reliable networks. - **WebRTC (Web Real-Time Communication): **A real-time communication protocol that enables direct, low-latency audio, video, and data transmission between browsers and devices without plugins, commonly used for video conferencing and interactive live streams. ### General Network Terms for Streaming - **ASI (Asynchronous Serial Interface):** a method for transmitting MPEG Transport Streams (MPEG-TS) over coaxial cable or optical fiber. It is widely used in broadcasting and video distribution to transport compressed digital video and audio signals between equipment. - **Baseband:** Baseband is considered the near zero compression of video being routed around the broadcaster facility. Typically a broadcaster will standardize on one type of standard to route video through the various equipment. - **Bonding: **Network bonding is a process of combining or joining two or more network interfaces together into a single interface. - **SMPTE 2022: **The Standard from the Society of Motion Picture and Television Engineers that describes how to send digital video over and IP network. ### Transport Stream Optimization and Error Correction - **ARQ - (Automatic Repeat Query):** ARQ is an error-control strategy used in a two-way communication system. These protocols are responsible for automatic retransmission of packets that are found to be corrupted or lost during the transmission process.  - **Contribution**: The process of sending live video from a remote location (e.g., a field camera or event) to a central broadcast or streaming facility. - **DSCP**: (Differentiated Services Code Point) a 6-bit field within the IP header of a network packet. The 6-bit value (ranging from 0 to 63) classifies the type of traffic and its desired priority level. - **Decoder**: The counterpart to an encoder; it decompresses video/audio streams for playback or further processing. - **Encoder**: A device or software that compresses raw video/audio into a specific format for distribution (e.g., H.264, HEVC). - **MTU (Maximum Transmission Unit): ** The largest size of a data packet that can be transmitted over a network without fragmentation. It plays a crucial role in network performance and efficiency, affecting how data is transmitted across different network interfaces. - **OTT (Over-The-Top)**: Delivery of video content directly to consumers via the internet, bypassing traditional cable or broadcast systems. - **PID (Packet Identifier):** A 13-bit field in an MPEG transport stream (MPEG-TS) that helps receivers distinguish between different types of data packets. Each stream—such as video, audio, subtitles, or metadata—is assigned a unique PID so that decoders can correctly process the data. - **RCA (Root Cause Analysis):** Analysis of problems anywhere in the ingest, processing, and distribution of streams to determine the exact underlying cause. - **TR 101: **Transport Stream Analysis Standard - **Transcoding**: The process of converting a video file or stream from one encoding format or bitrate to another. ### Stream Delivery - **ABR (Adaptive Bitrate Streaming)**: A technique in streaming where the video quality is adjusted in real time based on network conditions and device performance. - **CDN (Content Delivery Network)**: A network of servers that distributes and caches content geographically to reduce latency and improve delivery. - **Distribution**: Sending the final, produced video stream from a central location out to viewers or affiliates. - **DMVPD (Digital Multiple Video Programming Distributor):** A term used to describe services that provide multiple TV channels over the internet, rather than through traditional cable or satellite Society of Cable Telecommunications Engineers - **Multicast**: A method of broadcasting video over IP where one stream is sent to many receivers without duplicating the stream per recipient. - **MVPD (Multiple Video Programming Distributor):** A service provider that delivers multiple television channels to consumers. - **Unicast**: A one-to-one stream delivery method where each receiver gets a unique copy of the stream. - **VOD:** Video On Demand ### Signaling, Security, Scheduling, Ad Placement - **ESAM (Event Signaling and Management): **A standard interface used primarily for dynamic ad insertion (DAI) and content management in live and VOD (video on demand) workflows. It’s especially relevant as broadcasters transition to IP-based and hybrid environments where targeted and personalized streaming and broadcast becomes a key revenue opportunity. - **ESNI (Event Scheduling and Notification Interface): **Part of the SCTE 224 standard, which helps manage event scheduling, blackout enforcement, and content replacement in IP-based video delivery. ESNI enables broadcasters and content providers to dynamically adjust video streams based on predefined rules, ensuring compliance with licensing agreements and distribution policies. - **POIS (Placement Opportunity Information Service): **A component of SCTE-130 that manages available ad slots in video streams. This allows for the customization of SCTE 35 messages, which are used in downstream dynamic ad insertion and linear feed decoration. - **SCTE (Society of Cable Telecommunications Engineers): **A professional organization that focuses on advancing broadband and cable technology through standards development - **SCTE-35: **A standard for signaling ad insertion and content switching in digital video streams. It defines a way to embed cue messages within a transport stream, allowing broadcasters and streaming platforms to mark specific points where ads or alternate content can be inserted. - **SCTE-130:** A standard for digital program insertion in advertising systems. It defines interfaces and protocols that allow broadcasters and streaming platforms to manage ad placement efficiently. - **SCTE-224:** the Event Scheduling and Notification Interface (**ESNI**) standard, designed to help broadcasters and streaming platforms manage content distribution dynamically. It enables precise control over blackouts, regional restrictions, ad insertions, and alternate content delivery in IP-based video workflows. - **SDS (Signal Decision Service): **Used in broadcast and streaming workflows to manage ad insertion, content switching, or emergency alerts based on predefined rules. Two examples are **ESNI** and **POIS**. - **SPE (Signal Processing Event): **The XML message that is sent to the **SDS** when triggered by a relevant SCTE message. - **SPN (Signal Processing Notification):** The XML message that is returned from the **SDS** outlining any stream switches or **SCTE35** manipulation that should occur.