As the network grows and additional cameras are added, a PoE switch will be asked to supply more power. A Smart PoE switch allows an administrator to manage these increased power demands in a much more controlled manner, through user-defined port-priority assignments and policies.
A Virtual Local Area Network (VLAN) uses an Ethernet switch to partition a physical network, thereby creating distinct broadcast domains. VLANs are especially useful when an IP Surveillance network shares the same network infrastructure with other functions or applications, such as a corporate data network. By assigning the IP Surveillance traffic to a separate, distinct, high-priority VLAN, the traffic is assured to pass through the network swiftly and securely.
Some Smart PoE switches support a feature called Auto Surveillance VLAN, which simplifies VLAN configuration by automatically detecting any IP camera on the network. With no manual intervention, traffic from each camera is automatically assigned to a high-priority VLAN, which guarantees the quality and security of the surveillance information, even during periods of high network congestion.
Smart PoE switches enable administrators to easily examine the quality of the copper cables connected to each switch port. Tests can be initiated from anywhere on the network and run on each port during installation or troubleshooting to determine any potential cable errors. Diagnostics data includes:
" Cable connection: OK/Short Circuit/Open Circuit" Cable Fault Distance: If a cable fault is found, the test results will show the distance of the fault from the switch port" Cable Length: If test results show OK, they will also show the total length of the cable
Smart PoE switches may also feature a loop detection function, which can locate unintentional loops in a network. If a loop is detected, the switch automatically shuts down the port and alerts the administrator. Loop detection can be enabled on a single port, a range of ports or all ports simultaneously. Without such protection, undetected loops can wreak major havoc and cause serious traffic flow disruptions.
Unmanaged PoE switches don't have the ability to alert the network administrator after a change or disruption to the network. Smart switches, however, can send alerts to a network management system (typically SNMP-based) when such challenges arise. For example, a Smart PoE switch can send an alert to administrators when:" An Ethernet link goes up or down (e.g. an IP camera establishes or loses a link)" PoE power turns on/off for any port" A short circuit occurs on any port" A "Power Deny" action occurs on any port
In summary, while unmanaged PoE switches are considered a mainstay of IP surveillance networks because they are low-cost, easy-to-use and good for simple connectivity, more and more security professionals are realizing the tremendous benefits of upgrading to Smart PoE switches. The cost increase is minimal and these switches provide network administrators with a simple, easy-to-use interface through which the IP surveillance network can be configured and monitored from anywhere, anytime.
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