10 Explain the advanced features of a switch (PoE, Spanning tree, VLAN, Trunking, Port mirroring, Port authentication)
Switches have a more complex system of functioning than hubs. The role played by switches has increased considerable with the passage of time. Some of the advanced features of a switch are:
Power over Ethernet (PoE): As the name clearly indicates PoE, as a technology allows transmission of electrical power over a twisted pair Ethernet cable. Power and data are transferred simultaneously to provide power to remote devices. These remote devices can be remote switches, wireless access points etc. The primary advantage of this feature is that power is managed from a centralized unit. A UPS, Uninterrupted Power Supply is also required to be placed at the central unit. If PoE is not available then every remote device would have to be powered independently and be given an independent power supply.
Trunking: The term trunking means using multiple network cables or ports in a parallel set up. This is done to increase the link speed beyond the limits of a single port or cable. It works in the same way as link aggregation. To connect switches for setting up larger networks, higher capacity trunking links are used.
Port Mirroring: It is a part of the job of the network administrator to monitor network traffic and how a switch is working. This function is termed as port mirroring. For being able to use port mirroring, a copy of inbound and outbound traffic has to be configured. To examine the data that is forwarded to the port without interrupting the flow of the traffic a protocol analyzer is used.
Port Authentication: When users are authenticated on a port by port basis the function is termed as port authentication. Systems are allowed to connect to a LAN port only after authentication. If authentication fails, the systems are not allowed access any further. 802.1X is one such standard that is associated with wireless security.