10/100 (minimum) or 100/1000 (recommended) switch with enough ports for phones.

Direct path for phones to internet. Phones can not be in a double-NAT environment.

CAT5e wiring or better.

See this document for router and firewall requirements.

Fewer than 3 phones:


Shared with PCs: 10 Mbps / 3 Mbps

Not shared with PCs: 5 Mbps / 2 Mbps

3 to 5 phones:


  Shared with PCs: 20 Mbps / 5 Mbps

  Not shared with PCs: 10 Mbps / 3 Mbps

5-10 phones:


  Shared with PCs: 30 Mbps / 10 Mbps

  Not shared with PCs: 20 Mbps / 10 Mbps

Greater than 10 phones:


  Shared with PCs: 50 Mbps / 15 Mbps

  Not shared with PCs: 30 Mbps / 15 Mbps


In offices with more than 10 phones, a business-grade internet connection is a must. In most areas, Cable or Fiber is preferable to DSL.

Connecting PCs through phones in passthrough, or a shared LAN is not recommended.

Internet and phones may warrant an Uninterruptable Power Supply, if power loss would be an issue.

Internet connection should be tested to demonstrate the following:

 Consistent <100ms ping times to

 Less than 5% packet loss on a ping test of 100 or more packets.

 Traceroute should not show more than one gateway device present on the network.

 Phones absolutely can not be behind a firewall, especially SonicWall devices.