When it comes to network switches, there is no single best product. The different features, functions, and sizes of network switches must be compared for compatibility with the network at hand. For this reason, a careful analysis of needs, both those in the present as well as the next five years, is necessary to identify the right network switch for the job. An expected growth in personnel should not be overlooked.
To begin with, the network administrator should identify data servers, data storage servers, user communities, and target traffic flows. Analysing the traffic flow entails first measuring the bandwidth usage. Next, the data should be reviewed for capacity planning, performance tuning, and determining hardware improvement needs. After these reviews have been performed, network administrators are ready to head to eBay, where they can make informed and satisfying purchasing decisions.
Network Switch Performance
The switch must be able to support the network's bandwidth aggregation requirements, forwarding rates, and port density. This is especially applicable when selecting a network switch for the access, core, or distribution layer.
Access Layer Switch
The purpose of an access layer switch is to unite the network with end node devices. Amongst the more common connections facilitated by access layer switches are IP phones, modems, PCs, and printers, with the following features amongst those supported: Fast Ethernet or Gigabit Ethernet, link aggregation, Power over Ethernet (PoE), port security, and virtual local area networks (VLANs). Port security is especially important, as this is what the network switch uses when selecting what type and deciding how many devices can connect.
Distribution Layer Switch
Distribution layer switches also bear discussion for their pivotal role. The distribution layer switch collects the data from the access layer and then sends the information on to the core layer switches. After information packets are created on a Layer-2 switched network, this switch is responsible for segmenting the communication into VLANs. Without the routing provided by distribution layer switches, one VLAN would be unable to communicate with another.
Another important feature of distribution layer switches is the security they provide. Through the use of Access Control Lists (ACLs), distribution layer switches permit allowable types of traffic and stop those it deems unacceptable. Simply stated, ACLs enable the system administrator to regulate network device permissions.
Core Layer Switches
Core layer switches can be considered the high-speed network backbone. As such, it is essential that they are able to deal with high rates of information-forwarding. Another requirement of the core layer switch is that it supports link aggregation of 10GbE, the fastest Ethernet connectivity available. Without this capacity, the core layer switch would not allow enough bandwidth to pass through from the distribution layer switches. Core layer switches are critical with hardware and power redundancy as they allow for continuous operation unaffected by any power outages or instability.
Network Switch Considerations
The more devices are reliant upon the network, the more important careful network switch selection becomes. Therefore, an overview of the three layer switches should be accompanied by some relevant terminology.
Port speed varies depending on which switch ports are used, Fast Ethernet or Gigabit Ethernet; thus, ports should be chosen based on the number of devices and amount of information being transmitted. Fast Ethernet enables up to 100 Mbps of traffic per switch port; Gigabit Ethernet provides for 1000 Mbps per port. Although Fast Ethernet is significantly slower than its Gigabit counterpart, it is generally sufficient for business data and IP telephony traffic.
How many ports exist on a single switch is what is known as port density. Up to 48 ports per device may be supported with fixed configuration switches and four more, if expanded upon. Although two switches with lower port densities can be used to equal a larger one, this configuration is not preferable; they take up more space, use up two ports to connect to one another, and require twice as many electrical outlets. In the event high port densities must be supported, modular switches allow the network administrator to add multiple switch port line cards.
The forwarding rate is closely tied to the speed at which the switch processes data. The higher the processing speed, the faster the forwarding. This is all well and good unless the network switch is incapable of handling faster speeds. For example, at full wire speed, a 48-port gigabit switch produces 48 Gbps of data transfer; however, if the network switch can only accommodate forwarding rates up to 32 Gbps, the forwarding rate falls short of the switch's full wire speed.
Power over Ethernet (PoE)
When investigating network switches, Power over Ethernet is likely to be one of the first terms that comes up. PoE is precisely what it sounds like: the ability of the network switch to connect with a device via the network's existing Ethernet cabling. Virtually any device that utilises PoE, such as a wireless access point or a VoIP phone, can be operated wherever an Ethernet cable is run.
Network Switches vs. Routers
In practical terms, network switches serve to connect computers, servers, and printers. They coordinate communication like data, video, voice, and wireless access and are commonly utilised at business locations. In essence, the network switch controls communication between networked devices, making the transfer of information both efficient and secure. Thanks to network switch functionality, businesses save money and improve employee productivity through resource allocation and the sharing of information.
An easy way to distinguish network switches from routers is to remember that, while routers connect networks, the switches are what create the network in the first place. Switches communicate to all devices on a network; routers connect those devices to the Internet, where they can share information. The router essentially directs traffic, finding the best path for each packet of information. The table below identifies three strengths of both network switches and routers.
Congestion relief through isolated traffic; reduced collision due to separate collision domains; improved speed due to restarting, distance, repeater rules, and data segments
Simple network monitoring; quicker packet processing speed; significantly lower price than network switches
Despite these distinct benefits, the faster speed and reliability are often sufficient reasons for commercial operations to use switches in their network configurations. However, routers are still useful for small offices or small networks.
Managed versus Unmanaged Switches
If information technology professionals wish to manually configure a network switch, they select a managed switch. By configuring the switch to their specific needs, they not only receive added capacity and flexibility but also the ability to adjust the switch either remotely or locally. Most businesses use managed switches.
By comparison, an unmanaged network switch is essentially a plug-and-play operation. This type of network switch is the easiest to use, as it is preconfigured and ready to go. Aside from the lack of customisation, unmanaged switches also provide reduced network capacity. Unmanaged switches generally drive home networks.
How to Buy Network Switches on eBay
Now that you have learned a bit about network switches and how to use them for better connectivity, you are ready to visit eBay. The site is a technology lover's playground, with plenty of products for computing, networking, surfing, and transferring. eBay has switches for networks large and small, Fast Ethernet or Gigabit Ethernet-enabled, with port speeds of 100 to 1000 Mbps of traffic per switch port.
eBay makes it easy to compare products based on a number of factors, including manufacturer, seller, location, condition, and price. You can distinguish between network switches with varying levels of Ethernet capacity, including 10, 100, and 1000 Mbps, or focus your search on particular manufacturers, including Cisco and Omnistack. After a careful review of each product's features, you should be able to identify the network switches that fulfil your architecture needs. Be sure to take note of the seller's returns policy and test the network switch immediately upon receipt.
An important consideration in any computer network is the network switch. This piece of hardware is responsible for managing all communications by and between devices connected to the network. However, unlike a hub, which distributes information to all attached devices, network switches take note of the Ethernet address of each information packet and then forward the data only where needed. This not only speeds the transfer of information but also increases user productivity and, as a result, business profits.
Not all network switches are created equal however. As such, a thorough review of system needs and switch capabilities is in order before making a selection. The first step here is for the system administrator to take note of data servers, user communities, and traffic flows, both present and near term. Network switches boast different sizes, functions, and features. Those with more ports serve additional users, so capacity is an important distinction. With a firm grasp of network switches, buyers can head to eBay and find the product to serve their systems.