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
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 portal.nwvox.com
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.