This vendor-written tech primer has been edited by Network World to eliminate product promotion, but readers should note it will likely favor the submitter's approach.
Power-over-Ethernet networks inject power to the LAN cable to power attached devices, which turns out to be handy for IP-based surveillance systems. The same LAN cable that carries the IP video traffic can power an IP camera up to 330 ft. away.
PoE switches fall into three basic categories: unmanaged, smart and managed." Unmanaged switches provide basic connectivity between networked devices at a low cost. However, they aren't capable of changing settings or functions. They tend to be easy to use and good for simple connectivity only." Smart switches have a Graphical User Interface (GUI) with easy-to-understand controls, and are managed via a web browser. They provide intuitive guidance to users and are ideal for those who have no advanced network training." Fully Managed switches have a GUI, and also a more technical Command Line Interface (CLI), which allows network administrators to create scripts to program and manage multiple switches. They support advanced networking features that are often beyond the needs of an IP surveillance network.
When designing an IP Surveillance network, it makes smart sense to step up from an unmanaged PoE switch to a Smart PoE switch. For just a small increase in cost, network administrators can gain significant added capabilities, tools and benefits for their surveillance networks.
Smart PoE switches, for example, feature an easy-to-use, browser-based user interface and straightforward communication. An administrator simply browses to the IP address of the switch, and then uses the intuitive GUI as a simple vehicle for configuring and monitoring important elements and features in the network.
With Smart switches, an administrator can remotely turn off/on the PoE power to each camera via the graphical user interface. This comes in especially handy when a camera needs to be rebooted. This action can be manually controlled at anytime from anywhere on the network, or over the Internet. The administrator need not be at the camera's location, nor be in the same room as the PoE switch, which avoids truck rolls, saves time and money.
Some Smart PoE switches also support Time-Based PoE--an option that allows administrators to set a time window that determines when each camera is powered off and on. This can be useful for networks that need to be shut down during certain times of the day, or for automatically scheduling IP camera reboots on a periodic basis with no manual intervention.
Network administrators often need to know the power consumption for each switch port and the overall PoE power budget utilization. Capturing this data simply isn't possible with an unmanaged switch. A Smart PoE switch, however, can provide the following power consumption statistics in real time:" Actual PoE power utilization per port" Total system PoE power budget" Amount of total PoE power currently being used" Amount of total PoE power still available
Sign up for Computerworld eNewsletters.