Requirements for Using 12 High Bit Rate IP Cameras in a Network

When planning to deploy 12 high bit rate IP cameras in a network, several critical factors must be considered to ensure optimal performance and security. This comprehensive guide outlines the essential requirements that a network must meet to effectively accommodate the traffic generated by these advanced surveillance systems.

1. Bandwidth Considerations

In a network that will house 12 high bit rate IP cameras, sufficient bandwidth is absolutely crucial. The total bandwidth required will depend on the actual resolution and frame rates of the cameras, as well as the chosen compression codecs and settings. It is essential to understand that a continuous stream of data requires more bandwidth than an intermittent one due to streaming only during changes in the picture.

2. Understanding the Destination of Streams

Another key requirement is to determine where the streams are directed. Data from these high bit rate cameras could either be redirected to a Wide Area Network (WAN) or the Internet, or directly to a local recorder. Each path has implications for the amount of bandwidth required. Streams sent to a WAN or the internet will require higher bandwidth, whereas those sent to a local recorder may not, depending on the recorder's capabilities.

3. Continuous vs. Intermittent Streaming

The streaming mode (continuous or event-based) also significantly impacts bandwidth needs. Continuous streaming means the traffic is present all the time, necessitating allocation of bandwidth for each camera to be active. Event-based streaming, on the other hand, requires less continuous bandwidth but still needs to be managed properly to avoid network congestion.

4. Codec and Compression Settings

The choice of codec and settings can greatly influence the effective bit rate. Different codecs have different compression efficiencies, and settings can further adjust the bit rate. Consider the actual resolution and frame rate of the cameras, as these parameters will dictate the uncompressed bit rate. Efficient compression is critical to managing bandwidth effectively, but it must be balanced to preserve quality, especially for audio.

5. Audio Considerations

High bit rate IP cameras often support audio, which adds an additional stream that needs to be accounted for. Audio, though, is more sensitive to compression than video, and overly compressed audio can result in a loss of even basic speech clarity. If speech recognition is necessary, maintaining reasonably good audio quality is important.

6. Network Traffic Overhead

NAT (Network Address Translation) and other network traffic overhead can increase the bandwidth needed to support the bit rate used by the cameras. It is crucial to factor in these additional costs to ensure that the network can handle the full load.

7. Headroom and Resilience

To ensure smooth operation, there should be some headroom in the network resources, as continuous 100% use of bandwidth is not feasible on a packet network. Additional bandwidth is also required to accommodate occasional extra traffic, such as firmware updates, new camera setup mistakes, or unexpected network issues. Aim to size the network to limit video and audio traffic to 33-50% of the total bandwidth.

8. Testing and Validation

To ensure accurate assessment of bandwidth requirements, conduct thorough testing and measurements. Some camera models may provide misleading information about traffic compression needs, so it's essential to verify these details through practical testing.

9. Future-Proofing and Complications

High bit rate IP cameras are constantly advancing, and it's likely that your current system will not be the best option in a year or two. Consider future-proofing the network to accommodate potential equipment changes. Additionally, some cameras can send multiple streams at different rates simultaneously, so plan accordingly.

10. Local Recorder Considerations

If using a local recorder, the network must handle the streams sent to the recorder. Browsing or accessing the recorder data by users or network administrators may cause fluctuations in traffic patterns. Ensure the recorder can handle all camera data or plan for multiple recorders to distribute the load.

11. Network Traffic Patterns

While cheaper broadband links often offer fast download speeds, upload speeds may be slower. However, for this type of application, upload traffic may dominate the overall traffic pattern due to frequent updates and changes in camera settings.

12. Quality of Service (QoS) Implementation

Given the sensitivity of video and audio to compression, it's important to maintain quality. Skimping on quality can degrade the user experience and overall security. Implementing QoS (Quality of Service) policies can help manage network traffic effectively, ensuring that video and audio streams receive the necessary bandwidth for smooth delivery.

Conclusion

Deploying 12 high bit rate IP cameras in a network requires careful planning and consideration of various factors. Ensuring sufficient bandwidth, understanding the destination of streams, and managing continuous or event-based streaming are just a few of the key considerations. By following these guidelines, you can create a reliable and efficient surveillance system that meets the needs of today and tomorrow.