CPE Testing in the critical areas of Wi-Fi, voice and cyber security

Challenges in CPE testing for network operators

Wi-Fi testing in operator labs is often hindered by oversaturation of Customer Premises Equipment (CPE), making it difficult to obtain reliable performance data. A major international network operator needed comprehensive CPE testing across Wi-Fi, voice quality and cyber security domains. Their goals included:

• accurate Wi-Fi performance testing in realistic environments.
• objective end-to-end voice service quality evaluation.
• independent cyber security validation of new DSL modems and routers.

Our approach: End-to-end CPE testing across Wi-Fi, voice quality and cyber security

Wi-Fi testing

To overcome the limitations of the operator’s lab, testing was conducted both on-site and primarily at Resillion’s controlled lab environments. This allowed:

• Full control over Access Points (APs).
• Testing in diverse environments (e.g., apartment, terraced house, lab).
• Use of Resillion’s extensive device library for interoperability testing.
• Expertise across all Wi-Fi device types: APs, repeaters, Mesh networks, and various Wi-Fi clients.

Testing focused on characterising maximum Wi-Fi throughput (upstream/downstream) under varying conditions:

• Antenna positioning
• Distance between AP and client WAN/LAN configurations
• Single and multi-client scenarios

Additional verifications included:

• Basic settings (Radio, SSID, Channel, Bandwidth)
• Security protocols (WPA, WPA2, WPA3)
• Access control, WPS, Band Steering
  Event logs, Time control, QoS

Voice quality testing

The operator sought more than subjective audio checks or basic MOS scores. We developed a robust test suite incorporating:

• Objective MOS via PESQ (ITU-T P.862)
• Echo return loss, I/O attenuation, frequency distortion
• DTMF recognition, tone generation, hook flash detection
• Testing under ideal and impaired conditions (packet loss, jitter)

Cyber security testing

For new ZTE and Huawei DSL CPEs, the client wanted external validation. We provided:

• a black-box testing approach (no OS access or documentation)
• manual and automated testing, including VoIP traffic manipulation
• fuzz testing and software reverse engineering

Protocols tested included PPPoA, PPPoE, DHCP, Telnet, UPnP and TR-069. Key questions addressed:

• can admin access be gained?
• are there UPnP/TR-069 vulnerabilities?
• are there hidden features or backdoors?

Results: Delivering actionable insights and improved performance through CPE testing

Wi-Fi testing: Delivered reproducible, real-world results that helped the operator optimise Wi-Fi performance and reduce customer churn.
Voice testing: Provided detailed reports with graphical insights, enabling root cause analysis of voice quality issues (such as echo due to poor attenuation).
Cyber security testing: Identified critical and minor vulnerabilities, with risk classifications and actionable mitigation strategies. The operator avoided major security flaws in their CPE rollout.