Mean Time to Repair (MTTR) and Service Level Agreements (SLA) are terms thrown around by the carriers as if they really mean something. Trust me, they mean nothing. Typically a fibre circuit has a MTTR of 4 Hours. If you rely on this MTTR as something that will ensure you are back up and running in 4 hours, be warned. You need a backup circuit. As I write this post, one of our customer’s fibre circuits at the head office has been down for 22 hours. The techs working on the fibre cut went home last night, we don’t know why, it could be a union thing, or they ran out of cable. Whatever the case, the circuit is still down and the customer’s remote offices have little to no connectivity to their head office. The customer will be able to apply for a 10% credit of the monthly cost of that circuit from the carrier. It is no wonder that carrier is in no hurry to pay overtime to get it fixed. The costs would far exceed the penalty.
Most carriers have reworded the term SLA to SLO. The service level agreement is now a service level objective. Yet another out for them, as an objective really means best effort.
The solution to all of this is having a backup circuit that is connected, configured and tested. Test the backup quarterly to ensure that it will work as expected. There is nothing worse than having a backup that doesn’t work. When signing a contract with that carrier, pay little to no attention to the MTTR and SLA, as you cannot rely on it 100%. You can always try and negotiate bigger penalties, but whatever the penalty is, it won’t get you back up and running any faster, and if you do business on the Internet or rely on Private circuits to connect your branches your up time is worth more than any penalty you would be able to negotiate.