AMWA NMOS: The Whole Story

Presenters : Peter Brightwell / Brad Gilmer - BBC/AMWA

Year : 2019

dlp_document_download : C U R A T E D B Y I P S H O W C A S E T H E AT E R AT N A B – A P R I L 8 -11 , 2 01 9 AMWA NMOS: The whole story Brad Gilmer, Executive Director, AMWA Peter Brightwell, Lead Engineer, BBC Transport Automation Security Resilience Timing Monitoring Control Connection Discovery Technical challenges in an all - IP infrastructure ST 2110 ST 2059 ST 2022 -7 Networked Media Open Specifications • Specifications for discovering, connecting and managing resources • Developed by AMWA, published openly via GitHub • Tested at Networked Media Incubator workshops • Web -friendly: JSON, REST HTTP, WebSockets , message queues … 3 amwa -tv.github.io/nmos Specifications Documentation Developer resources Wiki IS -04, IS -05, BCP -002 EBU’s Technology Pyramid for Media Nodes Minimum user requirements to build and manage an IP -based media facility tech.ebu.ch/docs/tech/tech3371.pdf IS -06, IS -07 , IS -08 BCP -003 AMWA IS - 04 v1.2 Discovery and Registration What does it do? • Allows control and monitoring applications to find the resources on a network Why does it matter? • Enables for automation and reducing manual overhead • Essential for dynamic deployment How does it work? • Media Nodes locate IS -04 registry using DNS -SD (unicast preferred) • Media Nodes register their resource information with HTTP + JSON • Applications query with HTTP and/or subscribe with WebSockets 5 Registry Control and Monitoring Applications Media Nodes AMWA IS - 05 v1.0 Device Connection Management What does it do? • Provides a transport -independent way of connecting Media Nodes • Supports single + bulk connections, immediate + delayed connections Why does it matter? • ST 2110 does not specify how to do this • Danger of multiple proprietary approaches • Provides extensibility to other types of IP transport How does it work? • IS -04 provides information about Senders and Receivers • Control application sends instructions to Media Nodes • transportfile parameter conveys the connection information for ST 2110 streams 6 Control Application Media Nodes Media Node Sender Media Node Receiver Application Logic IS -04 Registry ST 2110 or other stream SDP SDP Multicast subscribe IS - 05 and IS - 04 working together AMWA IS - 06 v1.0 Network Control What does it do? • Lets broadcast control applications Why does it matter? • Ethernet switch output ports might only support a limited number of media flows before they start dropping packets ‒ This is different to what happens in a typical SDI router ‒ Which means corrupted video and audio How does it work? • "Northbound" API from network fabric’s controller • Provides topology discovery, flow authorization and assurances of flow bandwidth 8 Broadcast Controller Netw ork Controller NM OS Services Netw ork Control API IP Network NetConf, OF and others AMWA IS - 07 v1.0 Event and Tally What does it do? • Provides an IP -friendly mechanism to carry time -sensitive information • For example: camera tally information, audio levels, control panel status Why does it matter? • ST 2110 does not provide an equivalent to GPI functionality • Danger of multiple proprietary approaches • Consistency with other NMOS specifications How does it work? • Media Nodes emit and consume state and state change info • Lightweight messages sent using WebSockets or MQTT • Message flows connected using IS -05 9 An IS -07 message AMWA IS - 08 v1.0 Audio Channel Mapping 10 What does it do? • Allows channel -level operations within NMOS environments • For example: muting channels, swapping languages … Why does it matter? • Expected functionality for real world use • Not included in IS -05’s functionality How does it work? • Controller gets channel information from sending Node • … and sends mapping matrix to the receiving Node • Can also do sender -side matrixing AMWA BCP - 002 - 01 Natural Grouping 11 "tags" : { "urn:x -nmos:tag:grouphint /v1.0" : [ "MV PIP 1:Video" ] } What does it do? • Defines best practice for tagging groups of resources based on the function of a device, for example: ‒ 2110 -20, -30, -40 senders within a camera ‒ 2110 -20 receivers for multiviewer panes Why does it matter? • Can simplify "bulk" connections (often made on groups) • Not defined in IS -04 or IS -05 • Avoid different vendors taking different approaches How does it work? • Specifies a " grouphint " tag for NMOS JSON • Types of tags are maintained in a parameter register AMWA BCP - 003 API Security 12 What does it do? • Defines best practice for securing API communications ‒ Confidentiality, Integrity, Identification, Authentication, Authorization Why does it matter? • Users don’t want our IP systems hacked ‒ So are demanding security in the control plane • IS -04 etc can use HTTPS but don’t say enough about how to do that in an interoperable and secure way How does it work? • BCP -003 -01 specifies best practice for encrypting HTTP and WebSocket messages ‒ TLS 1.3 preferred, TLS 1.2 allowed. Recommends appropriate cipher suites ‒ Recommendations for X.509 PKI • BCP -003 -02 specifies best practice for authorization of API access ‒ OAuth 2.0 and JSON Web Tokens AMWA MS - 04 Identity and Timing Model 13 What does it do? • Formalizes concepts such as Source, Flow, Time Value … ‒ Re -examines the JT -NM reference architecture model taking into account many typical workflows • Provides a basis for new specifications Why does it matter? • Increased content reuse means increased reliance on end -to -end models • ST 2110’s RTP timestamps are insufficient, so we need a model for future extensions How does it work? • Separate content with business value (Sources, Flows) from the systems that process it • Explain through scenarios, formalize with UML AMWA IS - 09 System API 14 What will it do? • Provide Media Nodes with "global" information about their environment ‒ e.g. PTP settings Why does it matter? • We need systems to start working asap after (re)connection or power -up • DNS, DHCP, etc. provide a lot of what a Media Node needs … but not everything How does it work? • Read -only JSON resource NMOS Core 15 What will it do? • Provide common building blocks for new and updated NMOS specs Why does it matter? • Overhead of maintaining an increasing portfolio of specifications • Interactions between specifications makes updating complex How will it work? • "Factor out" repeated content from existing specifications ‒ RAML and JSON Schema definitions ‒ Type definitions ‒ URL schemes ‒ Documentation State of specifications Published • IS -04 v1.0, v1.1, v1.2 • IS -05 v1.0 • IS -06 v1.0 • IS -07 v1.0 • IS -08 v1.0 • BCP -003 -01 Final Approval (as of March 29) • BCP -002 -01 • MS -01 In progress • IS -04 v1.4 • NMOS Core and IS revisions • BCP -003 -02 API Authorization • IS -09 System API Testing • New work Incubated at AMWA workshops ‒ With VPN available for testing APIs in advance • AMWA now provides an automated test suite ‒ Python, open source, extensible ‒ Allows vendors to start testing in advance ‒ Saves time at events 17 NMOS Wiki • Help with the specs and docs • Information about available implementations and tools • Resources for developers • Resources for users github.com/AMWA -TV/nmos/wiki 18 Available NMOS Solutions AMWA is compiling lists of: • Open source implementations ‒ Python, C++, Javascript … • Freeware tools • Support in commercial products github.com/AMWA -TV/nmos/wiki/NMOS -solutions Disclaimer: listing on Wiki does not represent an AMWA endorsement or certification 19 NMOS at the IP Showcase Demonstrations • IS -07 Event and Tally • IS -08 Audio Channel Mapping • BCP -003 Authorization • TR -1001 20 Presentations • Mon 3.00pm : The Whole Story • Mon 3.30pm: Scalability & Performance • Mon 5.00pm: Things You Might Not Know • Tues noon: Audio Transport & Routing • Wed 9.30 – 11.00: API Security (3x present.) • Wed 11.30: GPI Replacement and Much More Some of those who have made NMOS happen …