Image Credit: MilesTek Corporation
Network switches connect network devices to host computers and allow a large number of devices to share a limited number of ports. They increase network capacity and speed by examining and filtering data packets. Switches also regenerate forwarded packets, reducing collision rates and permitting the use of additional nodes.
How Network Switches Work
Network switches receive packets and compare their source and destination addresses to a list of network segments and addresses. Packets are forwarded if the segments are different and filtered if the segments are the same. Often, high-traffic nodes or mission-critical computers are connected to a dedicated switch port.
This video explains how a networking switch works.
Types of Network Switches
The GlobalSpec SpecSearch database defines network switches as LAN or WAN capable, and allows industrial buyers to select boards or modules. As with other types of networking equipment, supported network protocols are important to consider. Switches support different types of Ethernet, and various VoIP standards.
Some suppliers describe switches as unmanaged or managed.
- Unmanaged switches have less network capacity, but are easy to install because they do not require configuration.
- Managed switches provide greater flexibility and capacity, but require proper installation for local and/or remote use.
Product and Performance Specifications
Network switches are also specified according to data rate, memory, and the number of ports. Because of protocol overheads, data transfer speeds may be less than listed. Network switch memory is used to store packets until the switch fabric can forward them to an output switch port.
Features and Applications
Network switches that are designed for use in computer rooms are often stackable or rack-mountable. Devices that support full duplexing can significantly increase bandwidths. Hardened products are also available, and are recommended for applications where high temperatures could damage sensitive components.
Related Products & Services
Network firewalls protect computer networks against unauthorized use or attack. They permit or deny access to private network devices and applications, and represent an important part of an organization's overall security policy. Firewalls may be software applications, hardware devices (such as routers), or a combination of both. They include turnkey products that are relatively easy to install as well as complex, multi-layer installations that require the expertise of a certified network administrator.
Network gateways interconnect networks with different, incompatible communication protocols. They perform a Layer-7 protocol-conversion to translate one set of protocols into another (for example, from TCP/IP to SNA or from TCP/IP to X.25).
Network hubs provide a central location for attaching wires to workstations. Often, these hardware devices include a network switch that controls how and where data is forwarded.
Network Repeaters and Extenders
Networking repeaters regenerate incoming electrical, wireless, or optical signals to preserve signal integrity and extend the distance over which data can travel. They are often used to connect cable segments in IEEE 802.3 networks.
Network routers are protocol-dependent devices that connect subnetworks, or that break down a large network into smaller subnetworks.
Network transceivers connect nodes and send and receive signals. In Ethernet networks, they are called medium access units (MAU).
VoIP and IP Telephony
VoIP and IP telephony allows PC users to make phone calls over the Internet or other packet networks via gateways and standard telephones.