In October 2026, Algar, a Brazilian telecom operator, announced that it had cut the time spent on technical configuration during installs by 60%. It uses an assistant that field technicians open in their app to configure the network, activate service and swap modems. According to TeleSíntese, technicians' calls to the back office asking for help with manual configuration dropped by more than 32%. Algar built that tool in-house, as large operators can. At a regional ISP, the same work (a technician typing parameters into the ONU's web interface and calling tier 2 when something doesn't match) moves out of the field once the ACS handles automatic provisioning.
In theory, the CPE connects, the server recognizes the device and pushes the standard configuration without anyone opening a browser. That happens at install time and again after every reset the subscriber does. In a fleet with three or four brands, the automation tends to break at predictable points, almost always tied to the model, the firmware or the preset.
What is automatic CPE provisioning?
Automatic CPE provisioning means the ACS configures the subscriber's ONU or router on its own, over TR-069 (CWMP), the first time the device makes contact and again after every factory reset. The technician installs it, the CPE talks to the server and receives DNS, NTP, remote access and whatever else the ISP has defined as standard.
Why manual CPE configuration doesn't scale
Configuring CPEs by hand doesn't scale because the cost comes back with every install, every equipment swap and every reset the subscriber does on their own. Most fixed broadband connections in Brazil are already fiber, according to the access dashboard from Anatel, Brazil's telecom regulator. Nearly every fiber connection ends in an ONU or a router that someone configured or still has to configure.
In support, the most expensive case is usually the reset done by the subscriber. They hold the button down because the internet froze, and the ONU comes back with the SSID and password printed on the label. Depending on the model, it may also lose the PPPoE credentials. Then the phone rings. Without automation, either tier 1 manages to walk a non-technical person through the web interface, or a truck roll goes out so someone can type in half a dozen fields.
What happens when the CPE reaches the ACS?
When the CPE reaches the ACS, it opens a TR-069 session with an Inform message. The server identifies the device and sends the configuration within that same session. The flow, in order:
- The CPE sends the Inform with manufacturer, serial number, model, firmware version and the reason for the connection. On first contact or after a factory reset, the event is
0 BOOTSTRAP. On a regular reboot it's1 BOOT, and on routine contact it's2 PERIODIC. - The ACS identifies the device (new or already registered, model and firmware) and the rule that applies to it.
- In the same session, the ACS sends the parameters from the pre-configuration or the preset, and the CPE responds whether it accepted or rejected each one.
- The ACS reads the values back to confirm they were applied and logs the result.
All of this assumes the CPE knows where the ACS is. After a factory reset, the ONU only looks for the server again if the URL is stored in custom firmware or gets sent again some other way, such as configuration pushed from the OLT. We cover that in our guide to TR-069 ACS URL setup in multi-vendor networks.
Why doesn't the preset work on every model?
The preset fails on some models because each vendor and each firmware implements the TR-069 parameter tree in its own way, and the ACS needs to know where every parameter lives on every model. Early versions of the CWMP data model had two roots, InternetGatewayDevice (TR-098) and Device, and Device:2 (TR-181) was introduced to replace both, as the Broadband Forum's CWMP data models page shows. In real fleets, though, both generations coexist. The Wi-Fi password sits under InternetGatewayDevice.LANDevice.1.WLANConfiguration.1 on one model and under Device.WiFi.AccessPoint.1.Security on another, and a preset written for one path won't find the parameter on the second.
The standard also lets vendors add their own objects, the branches that start with X_. The homologation documentation we maintain here at IXC Soft shows that many items, such as the WAN VLAN and the optical signal level, live in branches like X_HW_ and X_ZTE-COM_. That's why a model can show up in the ACS, report its serial number and uptime, and still fail to change the Wi-Fi password.
Homologation, our certification of a device model, applies to the specific hardware and firmware version that was tested, and a vendor update can move or remove a parameter. Some models also lack restore after reset: they get the configuration on first contact and come back from a factory reset with nothing reapplied.
How IXC ACS handles automatic provisioning
In IXC ACS, automatic provisioning is split into two functions. Device Pre-configuration handles new equipment, and Automatic Reconfiguration handles devices coming back from a reset.
Device Pre-configuration defines the parameters sent every time a new device reaches the ACS: web access, WAN and LAN DNS, NTP, Wi-Fi regulatory domain and LAN port binding. If the model is compatible, the parameter is applied, and any field left blank keeps the factory default.
Automatic Reconfiguration uses the presets and GPON profiles you have registered. It detects that the device came back from a reset, reapplies the configuration and checks that the values were actually applied, on models that support restore after reset.
To see what a device in your fleet supports, open the Device capabilities screen (Devices menu, select the device, three dots, About). It shows the homologation badge and rates each feature group as functional, partially functional or not supported. If the firmware exposes the parameter over TR-069, you can request homologation or find it in the device's parameter tree. If it doesn't, no ACS can configure that setting remotely.
On cost, the public reference we have comes from a Brazilian ISP: tens of thousands of support interactions over 6 months, between 2025 and 2026, comparing subscribers with and without CPEs managed by IXC ACS. Subscribers whose CPEs were in the ACS had 62% fewer truck rolls and a 7-day ticket reopen rate 6.2 percentage points lower, according to the methodology published with the ROI calculator. That result includes remote diagnostics and everything else the ACS was used for, so it can't be credited to provisioning alone, and it varies with the profile of each operation.
Checklist for turning on automatic provisioning
- Inventory your fleet by model and firmware version. For each combination, open the Device capabilities screen for one unit and check what works and whether the model restores its configuration after a reset.
- Run a pilot with one unit of each model: point it to the ACS, let the pre-configuration do its job, factory reset it and see whether the configuration comes back on its own.
- Agree on the firmware version with your supplier before closing a batch. When new firmware arrives, treat it as a new model and repeat the pilot.
- Build the pre-configuration with the minimum every device needs (DNS, NTP, web access, regulatory domain) and leave blank whatever should stay at the factory default. In Automatic Reconfiguration, associate each profile with the right model.
- Check ACS URL coverage. A device that doesn't talk to the ACS is outside any automation, and a factory reset is usually when it drops off.
Frequently asked questions
Does automatic provisioning work with CPEs behind CGNAT? Yes, because the configuration travels inside the session the CPE itself opens with the Inform. CGNAT gets in the way when the ACS needs to reach the CPE immediately (the connection request), and in that case the action waits for the next periodic contact.
Do I need to reconfigure the device after a factory reset? No, as long as the model supports restore after reset and finds the ACS again. On models without that function, the configuration has to be reapplied through remote support or in the field.
Can IPv6 be provisioned automatically? Yes, on models that support it. IXC ACS has an automatic IPv6 provisioning routine that checks IPv6 on every CPE contact or reboot and re-enables it when it's missing. Our article on IPv6 across your CPE fleet goes into more detail.
Where to start at your ISP
If you only do one thing this week, run the reset test. Take one unit of each model you're installing today, factory reset it on the bench and time how long it takes to come back with your configuration, if it comes back at all. Model by model, you'll see where automatic provisioning already works and where every subscriber reset still ends in a phone call or a truck roll.
If you'd like to see how this plays out with the brands in your fleet, click the button below and talk to our team.