Creative Team
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7 Jan 2019
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Option 66 is a feature that's available in most commercial grade routers which enables offering a 'provisioning server address' to any device on the same LAN and obtaining an IP via DHCP. This method of "broadcasting" the server address to multiple IP phones during the network boot up, versus configuring each one individually, significantly reduces the time and labour needed for most multi-device installations 👍

Without 3CX, we would need to set up a TFTP server, but 3CX has made it simple and super easy.

All we need to do is just set up the DHCP option below on the MikroTik router, then register the phones' MAC address on the extension on 3CX, and your phone will auto-provision by themselves every time they're booted.

The router must be, obviously acting as a DHCP server in order for this setup to be working.
  1. Select IP from the main menu.
  2. Click on DHCP Server.
  3. From the DHCP Server window, select the Options tab.
  4. Click on the "+" (plus sign) to add an Option.
  5. From the DHCP Option's window add the following:
    1. Name of Option (use to identify the Option)
    2. Code: 66
    3. Value: '<enter-URL-needed-for-specific-device-model>' (use single quotation)
  6. Click OK or Apply.
    Screen Shot 2019-10-31 at 11.01.08 AM.png
  7. Click on the Networks tab.
  8. Double click on the Network (for this example we are working with the default configuration).
  9. Select the DHCP Option (created in step 5).
    Screen Shot 2019-10-31 at 11.03.06 AM.png

  10. Click OK or Apply.
Now when you plugin an IP device on the same network (LAN) as the MikroTik, and it obtains an IP via DHCP, the router will redirect the phone to the provisioning server to check for new or updated configuration files.

Let me know if you find this tutorial is useful or perhaps you have any question or idea, feel free to post them down below! 👇
please check the files...
it's showing error


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This is for same LAN can we setup for WAN for different client with IP phones?
This is for same LAN can we setup for WAN for different client with IP phones?
DHCP works on Layer 2 in the OSI model, so I don't think it'll work for WAN IP phones.
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