** Attention: Some cameras are overwhelmed with the number of users attempting to connect to them. Please be patient and try again later if some of your favorites fail to connect. Some camera models only support 20 users at a time.
When you connect to a camera you are connecting DIRECT to the camera itself, not some super-powerful server that gives you the video. Imagine connecting through a cable to a personal camcorder. The camera is what's sending you the video and the more people that connect at once the more intense the processor usage on the device.
Some camera models (like Axis 2400 and Axis 2100) are limited to about 20 users at once before they shut down because they can't handle the load. Others (like Canon) seem to handle 50+ at a time and even when swamped they will at least pass back some video once in a while. There is no way to know how many people are connected to a device at once.
The cameras are each owned by different people/organizations, so it's also a constant battle to figure out which ones are offline for maintenance or just shut down by the owners. Some owners will often decide to password protect their cameras or take them offline.
The video frame rate displayed by Live Cams is based on the following factors:
The network connection type (Wifi or 3G/Edge). Wifi connections will use streaming video at the fastest rate possible. Cellular connections are restricted by Apple to 1 MB/min and therefore Live Cams resorts to pulling still frames at regular intervals. Apple has rejected the sale of Live Cams with streaming on cellular connections in the past so we have been forced to limit the speed.
The type of camera at the other end of the connection. Some camera models are more powerful than others.
The bandwidth performance at the camera's end of the connection. A powerful camera could still be slowed down by poor internet connections at the host.
The settings of the camera itself. Camera administrators may have the option of limiting transmit speed. They also may have the resolution set very high and this causes Live Cams to pull large amounts of network data per frame, slowing the response time.
How far away you are from the camera (geographically). Live Cams connects directly to the cameras and therefore the requests and data must transfer across the world in order for the cameras to respond. If you live in the United States and you are controlling a camera in Japan, expect delays :)