Much of this is fairly widely known in the telecoms sector, and is "open secrets". The sector is a pretty "closed shop" though, full of trade secrets and "prop

Much of this is fairly widely known in the telecoms sector, and is "open secrets". The sector is a pretty "closed shop" though, full of trade secrets and "proprietary" things. Underneath it all though, actually it's fairly simple once you get your head around it. If you work closely with an operator, even as a client, you'll see examples of this - the number of people brought to meetings from the vendor, versus from the operator. Who answers the questions. For a public example, see the Telefonica O2 outage in the UK (and Japan, I believe) due to an Ericsson certificate outage, and how much of a role Ericsson played in this. (https://www.theregister.com/2018/12/06/ericsson_o2_telefonica_uk_outage/ https://www.theregister.com/2018/12/06/ericsson_o2_telefonic...) Press releases also give bits and pieces away: https://www.ericsson.com/en/press-releases/2019/11/orange-opts-for-ericsson-operations-engine-in-managed-services-extension https://www.ericsson.com/en/press-releases/2019/11/orange-op... https://www.mobileeurope.co.uk/press-wire/9588-three-uk-joins-telefonica-by-outsourcing-core-management-to-huawei https://www.mobileeurope.co.uk/press-wire/9588-three-uk-join... Although they might not give the level of detail you're looking for, it should hopefully corroborate things.