An unmanaged switch simply allows Ethernet devices to communicate with one another, such as a

PC or network printer, and those are typically what we call “plug and play.” They are shipped with a

fixed configuration and do not allow any changes to this configuration

Managed switches provide all the features of an unmanaged switch and provide the

ability to configure, manage, and monitor your LAN. And this gives you greater control over how

data travels over the network and who has access to it.

Also, managed switches use protocols such as the Simple Network Management Protocol, or what

we call SNMP, for monitoring the devices on the network. SNMP is a protocol that facilitates the

exchange of management information between network devices. SNMP queries can determine the

health of the network or the status of a particular device. By displaying this data in an easily

understood format, IT managers located at a central site can monitor the performance of the

network and quickly detect and repair network problems without having to physically interact with

the switch.

It’s true that a managed switch is more expensive than an unmanaged switch. However,

there are many additional features you get with a managed switch, such as quality of service,

virtual LANs, redundancy, and port mirroring.

VLANs allow a switch to logically group devices together to isolate traffic between these

groups even when the traffic is passing over the same physical switch. This segmentation and

isolation of network traffic help reduce unnecessary traffic. For instance, you can segment traffic

between your finance and marketing groups, so that mission-critical finance information can flow

without delay to the finance users and get bogged down by marketing traffic. This allows better

network performance and in many cases provides an additional level of security.

Another important feature of a managed switch is redundancy. Redundancy provides the ability to

safeguard a network in case a connection or cable fails by providing an alternate data path for

traffic. Managed switches incorporate what is called Spanning Tree Protocol standard, or STP, to

provide path redundancy in the network. Using the spanning-tree algorithm, STP provides

redundant paths while preventing loops that are created by multiple active paths between switches.

STP allows for one active path at a time between two network devices, preventing loops and

establishing the redundant links as a backup to keep integrated systems available and preventing

expensive downtime, which network admins can appreciate.

And, finally, there is port mirroring. In conjunction with a network analyzer, this feature is useful to

diagnose problems. It copies the switch network traffic and forwards it to a single port on the same

switch for analysis by a network analyzer. You can use the analyzer on a monitor port to

troubleshoot network problems by examining traffic on other ports or segments. The benefit of this

is you can troubleshoot problems without taking the network out of service