• Voice over IP allows users to talk over a network connection.anruf image by Yvonne Bogdanski from Fotolia.com
  
  Though many voice over IP (VoIP) applications are relatively simple to install and use, without certain key software and hardware components, the software will not function correctly. Make sure you have these system features plugged in and operating before starting your VoIP installation.
  
  

Sound Card

• Some older computers and business models lack a sound card.soun card image by TEA from Fotolia.com
  
  Some business computers lack the fundamental necessity for a VoIP program: a sound card. Without a sound card, your computer cannot play sounds of any kind, or understand the input from a microphone, even if the device is plugged in and turned on. If your computer plays music and other sounds, your sound card is installed and operational. Almost any sound card will work with VoIP software.
  
  

Input/Output Devices

• Headsets are common VoIP accessories.headset image by Dron from Fotolia.com
  
  Though the sound card interprets the signal for VoIP transmissions, proper input and output devices ensure the parties involved in a VoIP connection can communicate. Speakers and microphone are required, though they come in many possible combinations of devices. Headsets combine the two, and are available with traditional 3.5 mm plugs, as well as USB connections.
  
  

Network Connection

• Different connection speeds will result in varying levels of call quality.network image by Allyson Ricketts from Fotolia.com
  
  Depending on use and connection speed, a VoIP program can significantly tax a network connection. Dial-up connections will not yield a desirable call quality, and even some DSL connections will falter or fail if the network has more than one user or application using bandwidth. A faster connection is necessary for a business consisting of multiple VoIP users.
  
  

System Requirements

• Most VoIP software runs adequately on older and less graphically capable systems. While some popular software options, such as Skype, run on many different operating systems, your computer may limit the compatibility of other VoIP software.