local loop Unbundling Dr. ZOUAKIA Rochdi ANRT

Presentation outline Definition of Unbundling local loop (LLU) Importance of LLU Types of LLU : Description and comparison between them Alternatives to LLU

Unbundling local loop (LLU) : -- Definition -- It’s provided at a point between the network termination point on the customer premises and the line-side of the access network operator’s local switch. It gives dedicated access to the local loop from the point of interconnect to the customer’s premises.

The importance of local loop Unbundling It introduces competition in telecommunications access and local services. [Not only for traditional telephony services, but also to ensure that the incumbent’s monopoly is not extended to include the rapidly growing market for high-speed data access] LLU provides a lower cost entry solution.

Unbundling local loop (LLU) : -- Interconnection -- Typically, the LLU can be from : the main distribution frame in the local switch Or, from a distribution frame in a remote concentrator unit

Unbundling local loop -- Scheme --

Local Loop Unbundling -- Types -- There are two types of LLU : Copper loop rental Bitstream access

Copper loop rental -- Generalities -- Access to the transmission medium in the local loop. Examples of transmission media are copper cables, coaxial cables and optical fibre cables. Technically, it is only possible to provide access to a copper transmission medium. This is because copper is the only transmission medium in which a separate physical path can be unbundled for the dedicated use of another operator. In other transmission media, available capacity is shared between many customers, so it is not possible to unbundle a particular local loop.

Copper loop rental -- Interconnecting points -- The copper loop rental can be achieved by interconnecting at any point in the access network such as : local switch, a remote concentrator unit, a street cabinet or an other flex-point in the access network However In practice, the entrant needs to co-locate its equipment ;  The point of interconnect is typically in a building – most commonly at the local switch or at the remote concentrator unit.

Bitstream access -- Generalities -- It includes both the transmission medium and the transmission system that is used to provide the customer service. [Examples of transmission systems include synchronous digital hierarchy transmission on optical fibres and xDSL transmission on copper cables.] Technically, bitstream access can be provided to any transmission system, since it only requires reservation of a specified bandwidth, rather than dedicated use of a physical loop.

Bitstream access -- Interconnecting points -- The point of interconnect for bitstream access is at the local switch. [It will certainly be no nearer to the customer.] It is possible to back-haul the bitstream service to a higher point in the network hierarchy. (for example, a tandem switch). [This enables the entrant to obtain bitstream access to a greater number of customers.]

Bitstream access -- Advantages -- The incumbent retains control and management of the entire access network. So, local loop unbundling does not interfere with the incumbent’s access network modernisation programme, nor does it increase the difficulty of managing multiple xDSL applications on copper pair cables.

Cooper loop rental and bitstream access (1\2) Bitstream access means that the entrant is reliant on the incumbent for the total transmission system. Entrants cannot therefore easily differentiate their services from those of the incumbent. [This may not matter in telephony applications, but could impair innovation and other benefits of competition in the high-speed data access services market.] With copper loop rental, the entrant should be able to deploy the transmission system of its choice (subject to any technical and operational constraints). [For example, xDSL could be used to enable the entrant to offer a bandwidth service that is not provided by the incumbent.]  On these grounds, copper loop rental appears to be preferable to bitstream access.

Cooper loop rental and bitstream access (2\2) But, with copper loop rental the entrant must physically interconnect with the incumbent at the termination of the copper local loop; whereas with bitstream access, interconnect may be at the local switch (or the incumbent may even provide back-haul capacity to allow interconnect at a tandem switch).

Cooper loop rental and bitstream access (3\3) There are three difficulties with interconnection at the end of the copper local loop : more points of interconnect are required. This increases the cost of local loop unbundling for the entrant ; the required location of points of interconnect are unstable, because most incumbents are engaged in a modernisation programme that involves converting some parts of the copper access network into fibre ; and some copper loop termination points are unsuitable as points of interconnect. For example, this may be the case where fibre has been extended to a flexibility point (for example, a street cabinet) at which there is insufficient space to locate interconnect equipment.

Alternatives to LLU Mainly, there is tree solutions : Local resale. Local interconnect. local loop infrastructure.

Local resale. The network operator provides wholesale services to the service provider and the service provider sells that service on to the customer. At one extreme, the reseller may not provide any additional functionality other than the billing system. At the other extreme, it may operate its own switch and operational support systems. Typically, local resale products are priced on the basis of a discount on the retail tariff, with the level of discount reflecting the proportion of costs avoided by the local network operator.

Local resale -- Scheme --

Local interconnect L ocal interconnect, in which an entrant operates its own local switch and interconnects on the network side of the incumbent’s local switch. Prices for local interconnect are typically regulated on the basis of the network operator’s costs plus a reasonable rate of return.

Local interconnect -- Scheme --

local loop infrastructure In this case the entrant lays its own transmission facilities between the local switch and its customers. This means that it is not required to use any other operator’s facilities to provide local services.

local loop infrastructure -- Scheme --