What’s Wrong with This?
Wally `Larman installed a four-camera network digital video system with the cameras connected to the customer’s existing LAN. Wally used the correct cable and terminators, connecting the four digital cameras to an existing network switch that had available ports, as shown in this diagram. (For simplicity, only the basic LAN devices are shown.) Wally then programmed each camera’s IP address to the IP address of the manager’s PC, but when Wally tried to test the system, he ran into trouble. Can you see what Wally did wrong and what he must do to correct the problem?
5-Minute Tech Quiz Answers
Here are the answers to the 5-Minute Tech Quiz and What’s Wrong with This? that appears on page 33.
- b – Digital systems transmit data as ones or zeros. Analog systems transmit video information with continuously varying levels.
- b – Codec is short for compress/decompress.
- d
- e – Additionally, network CCTV allows you to use the existing network cabling for the video images and to use standard network storage devices to archive and access video images.
- b
- d
- a
- a – Connecting digital cameras to an existing network requires the use of some bandwidth of the network to transmit images. If the network does not have sufficient capacity, adding video can slow the network down. You should speak to the IT manager before connecting any video devices to the network.
- d
- a – Some digital systems allow you to throttle or limit the amount of bandwidth that they will use.
- d
- b – PoE, Power over Ethernet, allows you to use a single network cable and connection for both video and power.
Answer to: What’s Wrong with This?
Wally’s problem is caused by the way he programmed the IP addresses in the cameras. Each camera needs its own unique IP address for the system to function. Wally should speak to his customer’s IT manager and obtain the necessary IP addresses and network information. Once he has this data, he then can reprogram the cameras and test the system. If the customer wants to be able to access the video over the Internet, Wally must get an external IP address and make sure that the IT manager opens any ports that are necessary for Internet viewing.