Monday 29 September 2014

Network Hubs and Switches

Hubs and switches function as a common connection point for the workstations, printers, file servers and other devices that make up a network. The main difference between hubs and switches is the way in which they communicate with the network.

What is a Hub?

A hub functions as the central connection point of a network. It joins together the workstations, printers, and servers on a network, so they can communicate with each other. Each hub has a number of ports that connect it to the other devices via a network cable.

How does a Hub work?

A hub is an inexpensive way to connect devices on a network. Data travels around a network in 'packets' and a hub forwards these data packets out to all the devices connected to its ports.
As a hub distributes packets to every device on the network, when a packet is destined for only one device, every other device connected to the hub receives that packet. Because all the devices connected to the hub are contending for transmission of data the individual members of a shared network will only get a percentage of the available network bandwidth. This process can slow down a busy network. 
A 10Base-T hub Ethernet Hub provides a total of 10 Mbit/sec of bandwidth, which all users share. If one person on the network is downloading a very large file, for example, little or no bandwi
dth is available for other users. These users will experience very slow network performance.

What is a Switch?

A switch is more sophisticated than a hub, giving you more options for network management, as well as greater potential to expand. A switch filters the data packets, and only sends the packet to the port which is connected to the destination address of that packet. It does this by keeping a table of each destination address and its port. When the switch receives a packet, it reads the destination address and then establishes a connection between the source port and the destination port. After the packet is sent, the connection is terminated. 


What are the advantages of a Switch?

A switch provides higher total throughput than a hub because it can support multiple simultaneous conversations. For example, when a 100Mbit/sec hub has five workstations, each receives only 20Mbit/sec of the available bandwidth. When a 10/100Mbit/sec switch is used every port on the switch represents a dedicated 100Mbit/sec path, so each workstation receives 100Mbit/sec of bandwidth.
Switches also run in full duplex mode, which allows data to be sent and received across the network at the same time. Switches can effectively double the speed of the network when compared to a hub which only supports half duplex mode. 

Why choose a LINDY Switch?

Switches improve the performance and efficiency of a network and should be used when you -
  • Need to make best use of the available bandwidth
  • Have multiple file servers
  • Require improved performance from file servers, web servers or workstations
  • Use high speed multi-media applications
  • Are adding a high speed workgroup to a 10Mbit/sec LAN
  • Plan to upgrade from 10 to 100Mbit/sec or Gigabit network
The standard features on all LINDY N-Way switches are -
  • 10/100Mbit/sec Auto-Negotiation on all ports, the switch automatically senses the speed of the attached device and configures the port for the proper speed. This simplifies deployment in mixed Ethernet and Fast Ethernet environments
  • Auto MDI/MDI-X auto-detects whether the connected cable type is normal or cross-over
  • Full or Half Duplex operation

Which Switch do I need?

If you are setting up a home or small office network an ideal solution is to use a switch with 5 to 8 ports. Switches can be linked together as your network expands.
For a good entry level switch to meet this requirement we recommend the LINDY 8 Port 10/100Base-TX Fast Ethernet N-Way Switch (Part No. 32982).
The compact LINDY 8 Port 10/100Base-TX Fast Ethernet Switch features Auto MDI/MDI-X on all ports, 10/100Mbit/sec Auto-Negotiation, and full and half-duplex modes and can be desktop or wall mounted.

If you require a larger switch with rackmount capability choose the LINDY 16 Port 10/100 Base-TX Fast Ethernet N-Way Switch (Part No. 25020) or LINDY 24 Port 10/100 Base-TX Fast Ethernet N-Way Switch (Part No. 25021).
These LINDY 19" rackmount switches are the perfect solution for expanding a 10/100 network.

Gigabit Ethernet Switches

LINDY GIGA N-Way Switches provide cost effective scalability of the network by utilizing the existing copper CAT5e cabling environment. Connectivity is not sacrificed because the same cabling is used for Ethernet, Fast Ethernet and Gigabit Ethernet.
These switches also incorporate VLAN technology. This feature is accessed from a console port on the switch and provides network administrators advanced configuration options and the ability to set up 'virtual' LANs which function as separate, secure network segments.
The LINDY 24 Port 10/100Base-TX + 2 Port 1000Base-T GIGA N-Way Switch (Part No. 25000) is ideal for linking backbone connections between servers and network switches.
24 Port 10/100Base-TX Switch with two 10/100/1000Base-T Gigabit Ethernet Ports with VLAN technology.

Managed Switches

A managed switch allows the ports on the switch to be configured, monitored, enabled and disabled. Switch management can also gather information on a variety of network parameters, such as -
  • The number of packets that pass through each of its ports
  • What types of packets they are
  • Whether the packets contain errors
  • The number of collisions that have occurred
You should look for the following features on a managed switch -
  • Gigabit Ethernet support
  • SNMP management and remote control capabilities
  • A management interface that can be accessed through an internet browser
  • Auto-negotiation support which auto-senses the speed and duplex capabilities of connected devices
  • Built-in expansion capability
The LINDY Fully Managed SNMP 24 Port 10/100Base-TX + GIGA Expansion N-Way Switch (Part No. 25030) is a high performance web-managed Layer 2 Switch that provides 24 Fast Ethernet 10/100Mbps ports. The built-in expansion slot can accommodate a number of different modules. Optional Gigabit/Fast Ethernet modules can be copper or fiber based and support 10/100/1000Base-T, 100Base-FX, and 1000Base-SX. This switch is ideal for organizations wishing to create a new, or upgrade their existing network infrastructure.
The switch features advanced SNMP (Simple Network Management Protocol) management and remote control capabilities, and supports an easy to use Layer 2 management interface that can be accessed through an internet browser.
Fully managed SNMP 24 Port Fast Ethernet and full Gigabit backbone support with remote management.
Using a managed switch can reduce hidden costs by using -
  • Switch and traffic monitoring to help head off problems before they occur, reducing user downtime
  • Management tools that offer an intuitive graphical user interface (GUI) that simplifies configuration and monitoring tasks
  • Management functions can be performed remotely using a web browser or directly via a console connected to the switch.
Hope this was helpful?

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