Understanding the Impact of Unlocked SDI Devices on SMPTE 2110 Networks

In the realm of media production and broadcasting, the transition to IP-based infrastructures has brought about significant advancements in flexibility, scalability, and efficiency. At the core of this transformation lies SMPTE (Society of Motion Picture and Television Engineers) 2110, a suite of standards defining the transmission of uncompressed video, audio, and ancillary data over IP networks. However, when SDI (Serial Digital Interface) devices within SMPTE 2110 networks are not properly gen-locked with their Black Burst signal, it can introduce various challenges and issues affecting the integrity and synchronization of media streams. In this article, we explore what happens on an SMPTE 2110 network when an SDI device is not gen-locked with its Black Burst signal and the implications it has on media production workflows.

Understanding Gen-Locking and Black Burst Signals

Gen-locking refers to the process of synchronizing multiple video devices, ensuring that their respective video signals are perfectly aligned in terms of timing and phase. In traditional SDI-based workflows, gen-locking is achieved using a reference signal known as Black Burst. Black Burst is a composite video signal that carries synchronization information, including timing and frame rate, ensuring that all devices within the production chain are synchronized to a common reference.

Implications of Unlocked SDI Devices in SMPTE 2110 Networks

When an SDI device is not gen-locked with its Black Burst signal in an SMPTE 2110 network, several implications arise, including:

  1. Timing Inaccuracies

Unlocked SDI devices may exhibit timing inaccuracies, resulting in misaligned video signals within the network. This can lead to synchronization issues, where video frames from different sources are not properly synchronized, causing visual artifacts, jitter, or frame drops in the final output.

  1. Lip-Sync Errors

Inconsistent timing between audio and video signals can result in lip-sync errors, where the audio component lags or leads the corresponding video. Lip-sync errors degrade the overall viewing experience, making content appear out of sync and unprofessional.

  1. Interoperability Challenges

SMPTE 2110 networks rely on precise timing and synchronization to ensure seamless interoperability between devices and components. When SDI devices are not gen-locked with their Black Burst signal, interoperability issues may arise, leading to compatibility challenges and difficulties in integrating different elements within the production workflow.

  1. Quality Degradation

Timing inaccuracies and synchronization errors can degrade the quality of video streams, introducing visual artifacts, stuttering, or distortion in the final output. Quality degradation compromises the overall production value of media content, affecting its appeal and marketability.

  1. Workflow Disruptions

In severe cases, unlocked SDI devices can cause workflow disruptions, resulting in downtime and delays in production schedules. Identifying and rectifying gen-locking issues requires time and resources, impacting the efficiency and productivity of media production workflows.

Mitigating Gen-Locking Issues

To mitigate the impact of unlocked SDI devices on SMPTE 2110 networks, broadcasters and media organizations can implement the following strategies:

  • Ensure that all SDI devices are properly gen-locked with their Black Burst signal, adhering to SMPTE standards and best practices.
  • Conduct regular checks and maintenance to verify the integrity and accuracy of timing synchronization across devices within the network.
  • Invest in monitoring and diagnostic tools capable of detecting timing inaccuracies and synchronization errors in real-time.
  • Provide training and education to production personnel on the importance of gen-locking and best practices for maintaining synchronization in IP-based media infrastructures.


Unlocked SDI devices pose significant challenges and issues in SMPTE 2110 networks, affecting timing accuracy, synchronization, interoperability, and quality of media streams. By addressing gen-locking issues proactively and implementing robust synchronization mechanisms, broadcasters and media organizations can ensure the reliability and performance of their IP-based production workflows, delivering high-quality content to audiences worldwide.