Livewire (networking)
Livewire is an audio-over-IP system created by Axia Audio, a division of The Telos Alliance. Its primary purpose is routing and distributing broadcast-quality audio in radio stations.
Livewire+ | |
---|---|
Manufacturer Info | |
Manufacturer | Axia Audio, a brand of The Telos Alliance |
Development date | 2003 |
Network Compatibility | |
Switchable | Yes |
Routable | Yes |
Ethernet data rates | Fast Ethernet, Gigabit Ethernet |
Audio Specifications | |
Minimum latency | 0.75 ms[1] |
Maximum sampling rate | 48 kHz[2] |
Maximum bit depth | 24 bits[2] |
The original Livewire standard was introduced in 2003 and has since been superseded by a second version, Livewire+. Livewire+ includes combatibility with the AES67 and Ravenna standards to allow interoperability with equipment from other manufacturers. Designed as a superset of Livewire functionality utilizing common protocols and formats, Livewire+ is available as an open standard through Axia's Livewire+ Partner Program.
Livewire+ provides flexibile routing and transport of audio streams using multicast networking, with the ability to connect any input to any output (known as "anywhere-to-anywhere routing"). Distribution utilises standard IP and Ethernet over twisted pair cabling.
Protocol
The following table lists ports and protocols used in Livewire systems.[3][4][5]
Port | Protocol | Multicast Address | Purpose | Notes |
---|---|---|---|---|
67, 68 | UDP | BOOTP Server/Client | Remote IP address assignment | |
93 | TCP | Livewire Routing Protocol | Also provides transparent passing of custom messages, similar to the Ancillary Data Transmission feature of AES3 | |
123 | UDP | Network Time Protocol | ||
514 | UDP | Syslog | Activity logging to a syslog receiver. | |
2055 | UDP | 239.192.255.4 | Multicast-based GPIO (CMsg2 protocol) | GPIO commands, GPIO node → console-type endpoint |
2060 | UDP | 239.192.255.4 | Multicast-based GPIO (CMsg2 protocol) | GPIO commands, console-type endpoint → GPIO node |
4000 | UDP | Livewire Advertisement and Source Allocation Protocol | Verbose advertisement and source allocation requests | |
4001 | UDP | 239.192.255.3 | Livewire Advertisement and Source Allocation Protocol | Periodic and verbose announcements;
Source allocation state announcements and responses |
4002 | UDP | 239.192.255.3 | Engine Supervision Protocol | |
4010 | TCP | Livewire Control Protocol | ||
4011 | UDP | 239.192.255.4 | LWCP for Accessory Modules | Module → Console |
4012 | UDP | 239.192.255.3 | LWCP for Accessory Modules | Console → Module |
5004 | UDP | 239.192.x.x | RTP Livewire Audio | Last two address octets pertain to Axia channel ID, e.g. 9999 = 39 15 (hex 27 0F) |
7000 | UDP | Livewire Clock | One device assigns itself as LAN-wide reference, all other devices slave to it | |
9997 | TCP | Protocol logging | Debug protocol logging for Element |
References
- "Best Practices in Network Audio" (PDF). Audio Engineering Society. 2009. Retrieved 30 July 2015.
- Introduction to Livewire+ (PDF), The Telos Alliance, May 2015, retrieved 30 July 2015
- "Configuring Windows Firewall for use with the Axia IP-Audio Driver" (PDF). The Telos Alliance. 31 October 2006. Retrieved 30 July 2015.
- "Axia IP-Audio Driver for Windows, rev. 2.5 manual" (PDF). The Telos Alliance. August 2010. Retrieved 30 July 2015.
- Steve Church; Skip Pizzi (10 September 2012). Audio Over IP: Building Pro AoIP Systems with Livewire. CRC Press. pp. 4–. ISBN 978-1-136-03057-4.