Technical Resources and AV-over-IP Toolkit
Setting the Timer
- Use the hours, minutes and seconds fields to set your desired duration.
- Countdown: Counts down from the time you set.
- Countup: Starts from zero and counts upward.
- After Zero: Choose what happens when the timer reaches zero:
- Flash Zeros: Digits flash at zero.
- Continue Negative: Timer continues into negative time.
Warning Thresholds
- Set two optional warning thresholds (in seconds):
- Orange Threshold: Digits turn orange when time is less than or equal to this value.
- Red Threshold: Digits turn red when time drops below this value.
- If both thresholds are met, red takes priority.
Visual Feedback
- Digits turn orange when time ≤ orange threshold.
- Digits turn red when time < red threshold.
- Red overrides orange if both thresholds are met.
Data Rate Converter
Storage Converter
Transfer Time Calculator
dB / Voltage / Power Converter
Ohm's Law (DC)
Delay & Distance
Pixel Density (PPI)
Viewing Distance
This section provides an overview of key protocols and standards used in Audio Visual over IP (AV-over-IP) systems. These protocols facilitate the transport, synchronisation, control and management of audio and video streams over IP networks.
AV-over-IP Knowledge Base
Detailed technical references and guides for key media networking and transport systems:
Developed by Audinate, Dante is a proprietary Layer 3 media transport suite. It delivers uncompressed, multi-channel, low-latency digital audio over standard gigabit networks. Dante utilises IP packets and routing, relying on the Precision Time Protocol (PTP IEEE 1588) to elect a master clock and achieve sample-accurate sync across all nodes.
AES67 is an open standard published by the Audio Engineering Society. It defines an interoperability profile to bridge distinct IP audio protocols (such as Dante, Ravenna and Q-LAN), enabling them to route and exchange audio streams directly. It mandates the use of RTP over UDP for transport, PTPv2 for clocking and multicast management via IGMP snooping.
NDI is a high-performance video-over-IP protocol developed by NewTek for live broadcast environments. High-bandwidth NDI uses a proprietary intra-frame compression codec (~150-250Mbps for 1080p60) to achieve sub-frame latency over LAN. NDI|HX (High Efficiency) uses H.264 or H.265 compression to enable remote, wireless, or bandwidth-constrained WAN video links (~10-30Mbps).
SRT is an open-source video transport protocol optimised for streaming high-definition video over unstable networks (such as the public internet/WAN). Built over UDP, SRT mitigates packet loss and jitter using ARQ (Automatic Repeat reQuest) retransmission buffers, while providing native end-to-end 128/256-bit AES encryption.
Ravenna is an open, licence-free real-time media routing standard based on Layer 3 IP protocols. Developed by ALC NetworX, it is highly optimised for broadcast environments, supporting sample rates up to 384kHz, DSD bitstreams and custom packet times. It is fully compatible with AES67 profiles.
AVB is a set of open IEEE standards operating at Layer 2 (Data Link) to guarantee media stream delivery via bandwidth reservation (SRP) and clock synchronisation (gPTP). Milan is the professional AV specification built on top of AVB to guarantee device interoperability. It requires specialised AVB-compliant network switches.
Q-SYS is an audio, video and control ecosystem by QSC. Q-LAN is its underlying media routing protocol, distributing uncompressed, low-latency audio, video and control streams over Layer 3 gigabit networks. It integrates natively with Dante and AES67 endpoints in software.
Protocol Reference Tables
Physical and Data Link (Layer 1-2)
| Standard | Type | Speed | Notes |
|---|---|---|---|
| IEEE 802.3 (Ethernet) | Physical/Data Link | 10M - 400G | Foundation for IP-based AV transport |
| IEEE 802.1Q (VLAN) | Data Link | N/A | Traffic segmentation and prioritisation |
| IEEE 802.1p | Data Link (QoS) | N/A | Priority tagging for time-sensitive data |
| IEEE 802.1AS (gPTP) | Timing | N/A | Generalized Precision Time Protocol |
| IEEE 802.1Qav | QoS | N/A | Forwarding and Queuing for Time-Sensitive Streams |
Network and Transport (Layer 3-4)
| Protocol | Layer | Use | Notes |
|---|---|---|---|
| IPv4 / IPv6 | Network (Layer 3) | Addressing & Routing | Core internet protocol |
| UDP | Transport (Layer 4) | Real-time streams | Low-latency, no retransmission |
| TCP | Transport (Layer 4) | Control, file transfer | Reliable, ordered delivery |
| RTP | Application (over UDP) | Media streaming | Real-Time Transport Protocol |
| RTCP | Control | Stream monitoring | RTP Control Protocol |
| IGMP | Network | Multicast management | Internet Group Management Protocol |
Synchronisation
| Standard | Accuracy | Application | Notes |
|---|---|---|---|
| IEEE 1588 PTPv2 | Sub-microsecond | AES67, Dante, SMPTE 2110 | Precision Time Protocol version 2 |
| NTP | Millisecond | General timekeeping | Network Time Protocol |
| GPS/GNSS | Nanosecond | External reference | Global positioning timing source |
Network Reliability and Redundancy
| Standard | Type | Recovery Time | Notes |
|---|---|---|---|
| SMPTE ST 2022-7 | Seamless Protection | Hitless (0ms) | Dual-path redundancy |
| IEEE 802.1w (RSTP) | Rapid Spanning Tree | 1-2 seconds | Loop prevention |
| VRRP | Router Redundancy | Sub-second | Virtual Router Redundancy Protocol |
| FEC (Forward Error Correction) | Error Recovery | Real-time | Packet loss mitigation |
IP Services (Network Plumbing)
| Service | Function | Protocol |
|---|---|---|
| DHCP | Automatic IP addressing | Dynamic Host Configuration |
| DNS | Name resolution | Domain Name System |
| mDNS / Bonjour | Zero-config discovery | Multicast DNS |
| LLDP | Device discovery | Link Layer Discovery Protocol |
| NMOS IS-04 | Device registration | AMWA Networked Media Open Specifications |
| NMOS IS-05 | Connection management | AMWA NMOS |
Control and Management
| Protocol | Type | Use Case |
|---|---|---|
| SNMP | Network Management | Device monitoring, configuration |
| HTTP/HTTPS | Web-based control | Device interfaces, REST APIs |
| WebSocket | Bidirectional control | Real-time web interfaces |
| OSC | Control protocol | Open Sound Control (audio/lighting) |
| Ember+ | Control protocol | Broadcast mixing consoles |
| NMOS IS-08 | Channel mapping | Audio channel routing |
Security and Access Control
| Standard/Protocol | Function | Notes |
|---|---|---|
| IEEE 802.1X | Port-based authentication | Network access control |
| TLS/SSL | Encryption | Secure communication (HTTPS, etc.) |
| IPsec | VPN / Encryption | Secure IP communications |
| MACsec (802.1AE) | Layer 2 encryption | Point-to-point or hop-by-hop security |
| RADIUS | AAA (Authentication) | Remote Authentication Dial-In User Service |
Cloud, Remote and Streaming
| Protocol/Tech | Type | Use Case |
|---|---|---|
| RTMP | Streaming | Legacy live streaming (Flash-based) |
| RTSP | Streaming control | Real-Time Streaming Protocol |
| HLS | HTTP streaming | HTTP Live Streaming (Apple) |
| DASH | HTTP streaming | Dynamic Adaptive Streaming over HTTP |
| SRT | Secure streaming | Secure Reliable Transport (low-latency WAN) |
| WebRTC | Browser-based RTC | Real-time communication (video conferencing) |
| RIST | Reliable transport | Reliable Internet Stream Transport |
Audio Protocols
| Protocol | Transport | Latency | Bit Depth/Rate | Notes |
|---|---|---|---|---|
| Dante | Layer 3 (IP) | Ultra Low (<1ms) | 24/32-bit, 48-192kHz | Proprietary (Audinate), widely used. PTPv1/v2. |
| AES67 | Layer 3 (IP) | Low (1-4ms) | 24-bit, 48kHz (typ) | Open Standard. Interop bridge. PTPv2. |
| AVB/Milan | Layer 2 (Ethernet) | Deterministic (2ms) | Various | Requires AVB-capable switches. |
| Ravenna | Layer 3 (IP) | Ultra Low | 24-bit, 48-192kHz | ALC NetworX, AES67 compatible |
Video Protocols
| Protocol | Bandwidth (4K60) | Compression | Latency | Use Case |
|---|---|---|---|---|
| SDVoE | 10 Gbps | Uncompressed / Light | Zero Frame (<0.1ms) | High-end ProAV, Medical, Command/Control. |
| SMPTE ST 2110 | Variable (1-25G) | Uncompressed | Sub-frame | Broadcast production (video/audio/data) |
| NDI (Full) | ~250 Mbps | Video Codec (Spatial) | ~1 Frame (16ms) | Live Production, Broadcast. |
| NDI HX | ~20-50 Mbps | H.264 / H.265 | Medium (100ms+) | Wireless, WAN. |
| IPMX | Variable (1-25G) | JPEG-XS | Sub-frame | Open Standard (SMPTE 2110 based). |
| HDBaseT | N/A (Point-to-Point) | DSC (if used) | Zero | Not IP, but category cable. 100m limit. |