Broadcast Beat Magazine 2017 IBC Show - Page 81

Overcoming network monitoring challenges on the way to IP workflows By Charlie Dunn, Video Product Line General Manager, Tektronix The broadcast equipment industry is in the pro- cess of making the transition to IP based trans- port for video, audio and data. This has led to development of a suite of standards including SMPTE ST 2022-6 for encapsulation of uncom- pressed SDI within IP packets and SMPTE ST 2110 for live IP production carrying separate video, audio and data packets. work traffic, router configuration, Precision Time Protocol (PTP) and Network Time Protocol (NTP) for timing. The biggest difference however is that in most data center applications, lost data can be re-sent – this is not the case with high bitrate video. The challenge for the network engineer is in understanding video technology and its impact on IT infrastructure. Although these standards open the door to an all- IP infrastructure, many broadcasters are looking at a steep learning curve as they begin to adopt IP technologies for live production. IP introduces many new technical and skills challenges. These include jitter, latency and the risk of dropped packets and network asymmetry that results in different path delays upstream and downstream. IP is a complex set of bi-directional protocols requiring knowledge of both the source and des- tination before deployment. No easy task Deploying IP for live video production applica- tions is effectively the collision of the two worlds of video and network engineering. Video engi- neers are comfortable with the use of SDI, coaxial cable, patch panels, black burst and tri-level sync for timing and above all, monitoring signal qual- ity. The challenge for the video engineer is to understand IT technologies and impact of an IT infrastructure on the video. On the other hand, network engineers are familiar and comfortable with, IP flows, protocols, net- The ultimate goal is an end-to-end IP infrastruc- ture, but getting there will be no easy task, and few if any broadcasters are going to tackle it all at once. Huge investments in existing technol- ogy and workflows mean that video and network engineers will need the tools to diagnose and correlate both SDI and IP signal types. Some monitoring equipment converts IP inputs signal directly into an SDI signal at the front end, but such an approach lacks true IP media analysis and the ability to examine the data packets to diag- nose IP traffic issues. The ideal monitoring solution for a hybrid IP/SDI network is one that can perform a diverse variety of IP layer measurements as well as monitor video and audio content. Monitoring and ease of use are critical to ensuring QoS levels across complex broadcast environments that typically involve compressed and uncompressed video transmis- sions through SDI and IP signal paths. This chal- lenge gets far worse if multiple tools are needed to test mixed SDI- and IP-based workflows due to Broadcast Beat Magazine • • 81