FTC to FTTP upgrade

[Suffolk2012]

We are on FTC hybrid broadband and have had multiple speed issues over the last 12 months.  We are currently on a 9 day LHC test whilst trying to survive on 3 to 5 mb/s can anyone explain what this means?

[Chrisee]

@Suffolk2012 one of the issues with FTTC partial fibre connections is that. Openreach are reducing the amount of work they will do on the copper network. Given that it is the length and condition of the copper cable that determines the speed of the broadband service this can be a major issue if your line needs much more than a few joints tightening.

I and Google cannot figure out what LHC means in this instance but at a guess they are monitoring the DLM system in the cabinet to see if the line can support the guaranteed minimum speed. If it can't Openreach will tell Sky who will then offer to release you from contract. Which is great if you have access to another line or can switch to mobile broadband if you can't things get complicated . There is something called the Universal Service Obligation for a minimum 10Mb/s service which lies with the BT group not with Sky see https://www.ofcom.org.uk/phones-and-broadband/access-to-decent-broadband/broadband-uso-need-to-know for more.

Obviously if full fibre has been laid past your address it would be a no brainer to upgrade but in areas where we see these issues it is highly unlikely full fibre can be offered commercially so will only be run with public money. Your local authority can bid for funds and contract with network providers from your user name this page explains more https://www.suffolk.gov.uk/business/economic-development-and-inward-investment/better-broadband-for-...

[TimmyBGood]

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@Chrisee wrote:

@Suffolk2012 

I and Google cannot figure out what LHC means in this instance 

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I get Large Hadron Collider, which seems excessive kit to test a broadband connection.

[Chrisee]

@TimmyBGood I excluded that from my search results as I also thought it unlikely but with Openreach who knows.

[Me134]

From AI (so don't blame me if it's wrong):-
 
A 9-day LHC test (Line Health Check) is a diagnostic monitoring period used by some UK broadband providers, such as Sky, to identify and resolve performance issues on Fibre-to-the-Cabinet (FTTC) connections.
During this period, the following typically occurs:
• Active Monitoring: Technical systems track your line's stability, sync speeds, and connection drops to pinpoint the root cause of service disruptions.
• DLM Interaction: It often runs alongside Dynamic Line Management (DLM), an automated system that adjusts your connection profiles (like speed and interleaving) to find the most stable balance.
• Stability Goal: It is primarily used when a customer reports severe instability or slow speeds, helping engineers determine if the fault is within the property or on the external Openreach network.
 
What to expect during the test:
• Fluctuating Speeds: Your internet speed may go up and down as the system tests different configurations.
• Brief Disconnections: You might experience short drops in service, usually at night, while the profile is updated.
• Limited Troubleshooting: Providers often ask you not to restart your router during this time, as manual reboots can be mistaken for line instability by the automated monitoring tools.

This test is similar to the standard 10-day "stabilisation" or "training" period that new broadband lines undergo, but an LHC is typically triggered as a specific response to an ongoing fault.