Special fault investigation assure

27 Nov 2021

You can ask for a Special fault investigation assure (SFIA) if you’d like us to look into problems on a customer’s digital subscriber line (DSL). We’ll investigate and try to find and fix any problems.

You can request an SFIA for local loop unbundling (LLU) products. Use it when a metallic path facility (MPF) or shared metallic path facility (SMPF) is working within the LLU contractual specification (SIN349) and is testing okay on our line test system. It works for both asymmetric digital subscriber line (ADSL) and symmetric digital subscriber line (SDSL) services.

If your customer has a voice issue on their line that tests okay (like a noisy line, or a missing or intermittent dial tone), you can also report it as a conscious decision to appoint (CDTA).


• We’ll investigate customer’s network for service improvements so you don’t have to.

• We offer SFI frames direct and SFI Assure which allows you to choose the most effective route to resolve the issue saving time and cost.

• Regardless the number of activities completed by the Engineer you pay a fixed price.

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