Unbundling local loop

Question

When we are dealing with local loop, we indicate the last mile of connection from the CABINET (or whatever else) to the subscriber. Now, I'm asking to you, the local loop is the medium of the access network or is always the copper/fiber wire that connect the cabinet to the clients?

Furthermore, with the unbundling local loop, can multiple carriers borrow all the infrastructure (core network + edge network + edge devices) except the local loop?

Or is the opposite, where multiple carriers borrow the last mile wired part, and then they have their own equipment in the edge network and their own core network?

Answer 1

when we are dealing with local loop we indicate the last mile of connection from the CABINET (or whatever else) to the subscriber.

At least in the UK it's the line from the telephone exchange to the subscriber, not merely the line from the cabinet.

Or is the opposite, where multiple carriers borrow the last mile wired part and then they have their own equipment in the edge network and their own core network?

Indeed it is the setup where multiple carriers can rent the local loop from the incumbent former-monopoly, then run their own equipment at the telephone exchange.

The exact details will vary by country. AIUI in the UK there are a number of variants.

• Fully unbundled: the provider takes control of the whole copper pair from exchange to subscriber and runs their own equipment for both voice and DSL.
• Shared unbundled: the provider takes control of the DSL band but voice remains with BT wholesale.
• Virtual unbundled: this is used for FTTC and FTTP services, since there are shared network components between the phone exchange and the subscriber (unlike traditional phone lines which are dedicated) the competitor can't be given direct low-level line access. Instead BT openreach handles termination of the shared fiber at the exchange and then hands off the data to the providers at the phone exchange.

Answer 2

The term "local loop" comes from analog telephony. It is also called the "last mile." The definition is not precise, and certainly things like "access medium" were never imagined when the term was created. In other words, there is no definitive answer to your question.

The physical connection to the subscriber is usually owned by a particular service provider. They decide whose traffic they allow on their network, but laws and regulations may require them to provide access to other providers.