4

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?

  • You mean "unbinding" the local loop, don't you? – Zac67 Dec 27 '17 at 16:06
  • 2
    And that local loop must have a really bad connection if you have to shout. – chrylis -on strike- Dec 27 '17 at 16:40
  • 1
    @Zac67: Surely "unbundling" rather than unbinding? – psmears Dec 27 '17 at 17:43
  • @psmears Thanks, that's the term - unblinding really put me off. ;-) – Zac67 Dec 27 '17 at 17:49
  • @Zac67: Yeah, fair enough :-) – psmears Dec 27 '17 at 17:50
3

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.
  • Thank you guys! I'm studying from various sources so i'm a bit confused. I'm asking again, what we mean for CENTRAL OFFICE? Supposing we are dealing with a FTTH architecture, the CO would be the closest closet with switches or equipment where fiber local loop ending? – rollotommasi Dec 28 '17 at 8:53
  • "Central office" is generally another term for telephone exchange. – Peter Green Dec 28 '17 at 23:14
4

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.

  • This vary per country. In France for example, the entire PST network was owned by the former national operator (France Telecom, now Orange) and it is bounded by law to give access to the local loop to the other operators. – JFL Dec 27 '17 at 15:59
  • Good point. I edited my answer. – Ron Trunk Dec 27 '17 at 16:02
  • Germany is very similar - most "TAL"s are still owned by Telekom and they have to provide line access to other providers (unbundled or total). Addtionally, they offer "bitstream access" where a much longer part of their network is used together with that of another ISP. – Zac67 Dec 27 '17 at 17:53

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.