Image Credit: Allied Electronics and Miles Tek Corporation

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.

 

How Hubs Work

Hubs receive data, but do not provide redirection or filtering. Although some can regenerate and retime signals, they cannot determine the best path. In the Open Systems Interconnection (OSI) model, network hubs operate at the physical layer (layer 1).

 

This diagram depicts the role of a USB hub in a network.

Image Credit: Broadband Buyer

Types of Network Hubs

There are three types of network hubs: passive, active, and intelligent.

  • Passive hubs or concentrators do not amplify or regenerate incoming signals before rebroadcasting them to the network. They do not improve the performance of local area networks (LANs), and may limit maximum media distances. Typically, passive hubs are connected to other devices in a star configuration.
  • Active hubs or multiport repeaters amplify the incoming electrical signals that contain data packets. They maximize network media distances and follow the same rules as repeaters. Although active hubs do not prioritize data packets, they can be configured as firewalls to examine them. If a received signal is too weak for rebroadcasting, active network hubs apply retiming and resynchronization techniques.
  • Intelligent hubs work like active hubs and include remote management capabilities. They also provide flexible data rates to network devices.

Product and Performance Specifications

The GlobalSpec SpecSearch database allows industrial buyers to specify network hubs according to voice and data protocols (e.g., Ethernet, CANbus). When selecting products, buyers should specify both the number of ports and the port type (e.g., RJ-45, USB). Speed is another important consideration.

 

Features and Applications

Some Ethernet hubs are PoE ready, meaning that they provide power over Ethernet capabilities (PoE). Although some network equipment is designed for use in computer rooms, other devices are hardened to withstand extreme conditions. In terms of applications,  network hubs may be used to connect computers to servers, printers, and other computers.

 

Resources

Network Magazine - All about Hubs

Network Devices: Hubs, Bridges, Switches, Routers

Hub / Switch


Related Products & Services

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