PLEASE NOTE: We highly recommend consulting an IT firm or network professional when configuring advanced network settings or devices.


For Quality of Service (QOS) rules on your router(s), please whitelist for all TCP and UDP traffic.

VoIP Compatible Routers

NOTE: The routers listed here are known to work reliably with our services. However… given the constantly updated firmware and physical changes made by manufacturers and the nature of cloud-based services, The Kotter Group cannot control the final configuration of the hardware or your computer systems/networks, or promise that any given router will work with your system, or guarantee that our information is 100% up to date.

  • Ubiquiti
  • Sonicwall
  • Meraki
  • WatchGuard
  • Fortigate
  • Adtran
  • Cisco ASA
  • EdgeMarc

Routers with Known or Possible Issues

  • Modem/Gateway Combo’s from any cable provider
  • Netgear
  • Linksys
  • D-Link
  • TP-Link
  • ASUS
  • Google
  • Apple
  • Off-Brand
  • MediaLink
  • Cisco RV and lower series
  • PfSense
  • Untangle
  • ZyXEL
  • DD-WRT
  • Tomato

General Router Configuration


  • Enable Consistent NAT
  • Unblock TCP and UDP Outbound
  • Check for latency spikes and other issues
  • Check for packet loss
  • Ensure you have sufficient bandwidth
  • Set TCP/UDP timeouts to at least 300


  • Enable SIP-ALG
  • DPI SIP Traffic
  • Use SIP Normalization
  • Use Static NAT’s for phones
  • Double NAT
  • Use SPI