Video analytics applications detect movement perpendicular to the camera more easily than movement toward or away from the camera. This is because objects moving perpendicular to the camera create more significant changes in the pixel patterns, making it easier for the analytics software to detect and analyze the movement.
Movement toward or away from the camera results in smaller changes in pixel patterns, which can be harder to detect accurately. References: Axis Communications documentation on video analytics and movement detection.

Adding network surveillance cameras to an existing Ethernet network will benefit from using VLANs (Virtual Local Area Networks) to keep the surveillance video separate from other network traffic. This separation reduces the risk of network congestion by prioritizing surveillance video traffic and ensuring sufficient bandwidth is available for video data. VLANs enhance network performance and security by segmenting traffic and minimizing interference from other network activities.

The device shown in the image is an SFP (Small Form-factor Pluggable) module. SFP modules are used to connect network devices over fiber optic or Ethernet cables, enabling high-speed data transmission. These modules are commonly used in network cameras and other IP-based devices to ensure reliable and efficient network connectivity. Axis provides various SFP modules that are compatible with their network devices, as outlined in their product datasheets and connectivity guides.