Switches and routers are the lifeline of your network. Servers, endpoints and outside services rely on this hardware to connect and communicate. So what is a network switch and what is a router?
What is a network switch?
Switches connect your various hardware and endpoints to the network. The connected hardware and endpoints could include VoIP phones, video conferencing systems, IP cameras, computers, printers and other IP-based devices.
Typically, a network switch will be deployed between your endpoints and the router. A router’s primary purpose is to connect your business’ network to the Internet or outside services. The switch provides your devices with connectivity to the router.
Switches vary by form and function. Models range from desktop switches with only a few ports, to rack mountable switches with upwards of 48 ports. Some switches can also be stacked, meaning they are all manageable from a single IP address, rather than managing them individually.
Unmanaged switches are ready to go, right out of the box. Managed switches give you the power to control how the network performs. For either type of switch, there are many features to be aware of and consider.
Prioritizing traffic and QoS
A switch can provide identification of specific devices on the network. Statistics for bandwidth usage and traffic optimization are available as well. A managed switch lets you prioritize traffic for important devices such as VoIP phones, while an unmanaged switch performs this task automatically.
Enabling QoS (“Quality of Service”) on a switch, for example, will ensure that traffic is prioritized for voice and video services.
Securing the network
Security protocols onboard switches help to guarantee that only authorized users can access the network. Ideal for switches used with wireless access points or remotely accessible devices.
Guests connected to your company’s WiFi won’t have access to restricted areas of the network. Likewise, granting employees remote access to devices such as IP security cameras won’t open up the network to unauthorized users.
Firewalls and secure routers provide an important layer of security. However, switches are the final demarcation point between your network and the various endpoints.
Power over Ethernet
A switch with PoE (“Power over Ethernet”) can power a PoE-enabled device through the same Ethernet cable providing network connectivity—no AC adapter or external power supply is required.
You’ve probably noticed that some VoIP phones with PoE support do not include AC power supplies. An optional AC adapter is likely available, but the manufacturer assumes that you will be powering the device via PoE.
Switching rates and connectivity
SFP uplink ports, data rates and the switching capacity of the appliance are also important to consider. Although they are not as critical as the previously mentioned features, they could become important as your network (and business) continues to grow.
Uplink ports provide interconnectivity between switches. This is important for stacking (when applicable) or for creating redundancy and resiliency in the event of hardware failure.
Gigabit-speed Ethernet connections are becoming the new norm. IP devices and computers demand more speed from the network than ever before. Switches with 10/100/1000Base-T RJ45 ports support gigabit-speed connectivity.
A final aspect to consider is the switching capacity. In other words, how fast the switch can direct traffic and data packets. An overwhelmed switch will create a traffic jam on your network.
What is a router?
The basic function of the router is to connect your network to outside services, such as the Internet or a VoIP service provider. Internet service providers utilize large routers and session border controllers to communicate with end users and carriers. Businesses maintain intranet connections and offer remote access to employees through routers. Routers for home use connect your laptops and other devices to an Internet service.
Routers are the front door to your network. Security is a major topic in the business IT world. Without security, it’s like leaving the door to your house wide open after you leave for work every morning. Routers are increasingly offering better security protocols and protection from unauthorized access and attacks.
Specialized routers are equipped to uniquely handle voice networks or data networks. These routers are ideal for businesses that choose to create, for example, a dedicated network for their VoIP phones and video conferencing equipment, and a network for their computers and other machines.
Power over Ethernet
explanation and uses
Power over Ethernet, also known as “PoE,” is a technology that enables an Ethernet cable to deliver DC power to a device. The Ethernet cable can carry both data and power along its pairs of wiring.
PoE eliminates the necessity for AC power adapters, or electrical wiring where AC outlets are not readily available. Many PoE-enabled devices like VoIP phones, for example, will not come packaged with AC power adapters (although they may still support them or require them for accessories).
Switches are deployed to connect IP devices to the network. An Ethernet cable carries the signals from VoIP phones, IP cameras and other endpoints to the switch. Since the switch is the first point of embarkation for these devices, it’s also the source for PoE. Switches with PoE ports can deliver power to PoE-enabled devices via Ethernet.
DC power current:
IEEE’s PoE standards
The Institute of Electrical and Electronics Engineers (“IEEE” for short) sets the universal standard for Power over Ethernet. Two standards, named 802.3af and 802.3at, are currently in use by PSEs and PDs.
The 802.3af standard supports up to 15.4 Watts of power, while the 802.at standard supports up to 51 Watts of power. The 802.at standard is more commonly known as PoE+ or PoE Plus.
More demanding devices like video phones and IP cameras will require PoE+, while most VoIP phones support the lower powered 802.af standard. Large displays and video applications have an incredible strain on a device’s power requirements.
Different classes and power requirements
A powered device will support either 802.3af or 802.3at. In addition to this standard, the device also supports different classes. The class of PoE determines how much Wattage is required to power the device.
Powered devices will signal to the power sourcing equipment how many Watts to deliver through the Ethernet cable.
If you are using a network switch to power your PoE-enabled devices, keep in mind the total PoE budget allotted to the switch. A switch with a 62W budget cannot effectively power eight devices requiring, let’s say, 15W of power each. Additional power supplies or switches will be necessary.
Switches without PoE
So you bought a new VoIP phone. It supports PoE and it didn’t come packaged with an AC adapter. Unfortunately, your network switch does not support Power over Ethernet. Time to buy a new switch too?
Install a PoE injector between phone and network switch. The injector supplies power to the phone over Ethernet, even if the switch does not support it.
IP camera manufacturers such as Axis provide PoE midspans specifically designed for high-powered PTZ cameras. A midspan is a purpose-built PoE injector.
The future of Power over Ethernet
As some design engineers see it, Power over Ethernet could become the universal standard for powering a wide range of equipment. No more wall plug adapters or expensive electrical wiring. All you’ll have to do is run an Ethernet cable.
Powering a video conferencing system or computer over Ethernet is still on the horizon. In the grand scheme of things, PoE technology is still young, and the future looks very bright.