Known Issues:

  1. Cannot disable DNS relay/proxy on all hardware and firmware versions we have encountered.  This causes intermittent registration failures on just Polycom phones.
  2. We do not know if SIP ALG can be disabled or not.


  1. Login to your router.
  2. Look through each configuration page to see if your router has the option to disable SIP ALG- this option is usually found under a Firewall or WAN setup page.
  3. Look through each configuration page to see if your model and firmware has the option to disable DNS relay/proxy - this option is usually found under a page titled LAN Setup or DHCP Server.
  4. If you router does not have 1 more or both of those options, then you or your IT will need to upgrade the router's firmware to the latest version.
    • Smarsh Hosted Services cannot upgrade the firmware for you, but you or your IT can contact Netgear for help upgrading the firmware.
  5. After upgrading the firmware, repeat steps 2 & 3.
  6. If your router still doesn't have the option to disable SIP ALG and DNS relay/proxy, then you will need to replace the router with a Recommended Router.
    • Smarsh Hosted Services cannot setup the new router for you, but your IT or the manufacturer of your new router can help you.  They will need to move settings from the old to the new router to ensure your computers and other devices on the network work properly.

Additional Resources:

  1. Recommended Routers.
  2. Recommended Switches.
  3. Recommended LAN Configurations.
  4. Network Ports and Protocols for HPBX phones.