CityFibre ONT

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CityFibre ONT
CityFibre ONT installed
CityFibre ONT ports
CityFibre ONT


This page has information about the CityFibre provided ONT - the box that connects the CityFibre connection to your own router. ONT stands for Optical Network Terminal, sometimes (mistakenly) called a modem.

  • In short, the ONT in installed inside the customer's premises by CityFibre and converts the fibre connection from the outside world in to a RJ45 port which you plug in to your router with a CAT5 cable.
  • The ONT requires power, and a UPS is recommended, see our VoIP_Power page for suggestions.

  • For help with router configuration for CityFibre connections, please see: General Router Settings page
  • The ONT is a 'Calix 801G GigaPoint v2' device and measures 10.16x2.07x3.25cm (WxHxD).



There are four LEDs on the CityFibre ONT:

  • Power - can be Green/Red/Amber
  • Broadband - indicates the ONT has a connection to the CityFibre equipment
  • Service - indicates a fault on the 'WAN' side of the ONT
  • Ethernet - indicates the connection to your router

State of the LEDs

When working properly, the items in bold for each light below indicates a good connection/service:

  • Power:
    • Solid Green: Device has booted up ok
    • Amber: performing an upgrade
    • Red: Failed to boot, it has a problem
    • Off: has no power or is really broken!
  • Broadband:
    • Solid Green: physical connection is established to the fibre
    • Flashing red and then green: Not able to establish a stable connection - re-seat the green fibre plug to the ONT to make sure its connected securely.
    • Off: Can't detect the optical cable
  • Service:
    • Solid Green: Internet service has been established
    • Off: There is a problem
  • Ethernet:
    • Green: connected to your router
    • Off: not connected to your router/device


There is no end user access to the ONT's configuration or status pages. There are two things a customer can perform though:

  • Reboot
  • Reset

Reboot the CityFibre ONT

You can pull the power cable, wait a few seconds and plug it back in again. This is safe to do and will mean the ONT reboots and reconnects to the fibre network. Alternatively, pressing the reset switch for less than 5 seconds will cause a reboot.

Reset the CityFibre ONT

Use a paperclip, or similar, and hold in the reset switch for 10-15 seconds. This will cause a reboot and factory reset of the ONT.

Other information

CityFibre VLAN ID

Important: The customer's router will need to talk PPPoE on VLAN 911.


  • Can pass Jumbo frames (up to 1900 bytes, but that's way higher than what's needed to pass 1500 byte packets inside of PPPoE) - so if your router supports RFC4638 (see 1500 byte MTU) in PPP, then you can pass 1500 byte packets. Depending on your router, you may need to set your WAN interface's MTU manually to 1508.
PING ( 1472(1500) bytes of data.
1480 bytes from icmp_seq=1 ttl=59 time=4.97 ms


  • Input voltage: 12 VDC (nominal), 10 VDC (min.), 15 VDC (max)
  • Power Adapter: 12 VDC, 1.5 A Typical
  • Power: 5 W, Peak Power: 7 W
  • PSU/connector: 12V DC 0.5A, tip positive.