To 2009, then, and the advent of Carrier Pre-Select (CPS), proposed by the Independent Communications Authority of South Africa (ICASA), widely seen as a precursor to LLU. CPS has been used by a large number of countries to kick-start the free flowing competition that should be the consequence of LLU, allowing smaller telcos to compete with the incumbents. The idea behind it is that it’s a mini version of unbundling in that it allows customers to choose their service provider and make calls over another providers’ network, usually accessing this using a prefix. Eventually, moves are made to implement automatic pre-select; the fact that, in South Africa, this second phase at time of writing would exclude cellphone users (who are believed to account for around 90% of calls made in the country) has raised some concerns.
With CPS, there’s no physical change to the current infrastructural set up, the carrier simply pays an interconnection fee to the network provider where the call is terminated – a sort of LLU “lite”, offering a virtual solution to the LLU problem and paving the way for the latter’s roll-out. The main advantage to consumers is that it usually creates a price war of sorts, meaning they can shop around for the best value. Providers, meanwhile, rather than looking to invest in rolling out their own physical infrastructure, usually look to services as their key differentiator from the competition, leaving end-users in an attractive position.
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The Local Loop Unbundling Committee (LLC) indicates that a hybrid comprising of three unbundling models is likely to be how the South African version of LLU looks. According to the LLC, these models are:
• Full unbundling: Also known as “raw copper access” this is where the competitor leases the line from the incumbent and has full control over the copper pairs, allowing them to offer all available services. Pricing is regulated but the incumbent retains ownership of the loop and responsibility for maintaining it.
• Line sharing/shared access: A form of full unbundling, this allows users to take voice and data services from two different suppliers. The incumbent retains control over the copper pair while allowing a competitor to lease part of the spectrum to offer services over the non-voice part of the loop. This model allows users to shop around for their preferred broadband provider without having to install another line. This method is prone to “crosstalk” and slower speeds.
• Bit stream: Wholesale access that a company, such as an ISP, to buy xDSL products from the incumbent, which retains control over the subscriber’s line and can therefore decide which services the competition can offer. As such, this version of LLU seriously limits the level of genuine competition and is widely viewed as a disincentive to rolling out improved technologies on the part of the incumbent. The service is often appealing to ISPs but not to organisations seeking to compete fully with the incumbent telco. For this reason, some countries do not consider bit stream to be part of the LLU process.
http://www.itwebinformatica.co.za/i...=74:converging-communications-2009&Itemid=123