BS/EN 50700-2014 pdf download.Information technology Premises distribution access network (PDAN) cabling to support deployment of optical broadband networks.
The ADP may be co-located with the PD. SDs are implemented as required. There is no restriction on the number of SDs between the PD and the SI provided that the performance requirements of 6.3 are met. See 5.8.2 for the minimum number of functional elements.
Where the ADP is co-located with a building entrance facility (BEF). there is no external cabling subsystem. Where an SI is co-located with a building entrance facility (BEF). there is no Internal cabling subsystem.
Distributors shall not contain any system specific components such as passive splitters or WDM components and there is a direct connection for each optical fibre between an SI and the ADP in all the configurations (Figure 4, Figure 5 and Figure 6).
5.4 CablIng subsystems
5.4.1 External cabling subsystem
The external cabling subsystem extends from the ADP (in Figure 4 and Figure 5) to the distributor
associated with a BEF. When present, the subsystem includes:
a) the cables (outdoor cables) outside the building and extending into the building, through the BEF to the distributor associated with the BEF;
b) any cabling components in the distributors outside the building. The cabling subsystems may comprise:
c) optical fibre cables which are spliced or terminated with connectors at the distributors to allow:
1) the re-distribution of the number of optical fibres within the cables (e.g. one cable containing 24 optical fibres divided into 6 cables containing 4 optical fibres);
2) a change of cable construction;
The internal cabling subsystem extends from the distributor associated with a BEF (in Figure 4 and Figure 5) or the ADP associated with a BEF (in Figure 6) to the Si. The subsystem includes:
a) the cables inside the building (indoor cables) between the distributors (in Figure 4 and Figure 5) or the ADP (In Figure 6) associated with a BEF and the SI;
b) any cabling components in SDs inside the building;
c) the mechanical termination of the cables at the SI.
The cabling subsystems comprise optical fibre cables which are spliced or terminated with connectors at the distributors to allow:
1) the re-distribution of the number of optical fibres within the cables (e.g. one cable containing 24 optical fibres divided into 6 cables containing 4 optical fibres);
2) a change of cable construction.
Where the premises comprises a single multi-subscriber building, the BEF may be at the premises boundary.
In such cases, the PD replaces the SD associated with the BEF for this subclause.
Where the premises contain multiple single subscriber buildings the SEF in each building replaces the BEF for this subclause.
5.5 Design objectives
The cabling specified provides the service provider with an optical transmission performance capable of supporting the broadest set of existing and emerging applications within the environmental conditions defined in 6.2 and therefore provides the longest operational life. This will minimize disruption and the high cost of re-cabling.
The design of pathways and spaces shall consider the risks to services to subscribers associated with unauthorised access (e.g. eavesdropping or denial of-service).
The installation of additional pathways to enable the installation of additional pathway systems and/or cables should be considered (see EN 50174-2 and EN 50174-3 for planning information).
5.6 Accommodation of functional elements
5.6.1 Closures providing protection to optical fibre cables and cable elements
Closures are used to provide protection to optical fibres cables and cable elements at the following functional elements:
Test interfaces to the PDAN cabling exist at the ends of the complete cabling subsystem i.e. at the SI and at the optical fibre end-face prior to connection to the access network at the ADP. If it is required to measure the transmission performance of the PDAN cabling using techniques in accordance with EN 61280-4-2 (see 6.3), it may be necessary to terminate the optical fibre at the ADP with appropriate connecting hardware.
There is no test interface for the PDAN cabling at the OAR The OAP enables a service provider to install an ENTI within the PDAN cabling which may then be used to perform a testing function on the complete access network as configured by the service provider.
5.7.2 Cabling
PDAN cabling is. if required, an application-independent cabling system that may be tested between the specific test interfaces as detailed in Clause 6.
Once connected to an operator’s access network at the ADP, the PDAN cabling is part of the complete access network transmission path and extends from the operator site via the LOC to the customer premises equipment (CPE). The transmission performance of the PDAN cabling within the complete access network is not specified in this standard and depends on the configuration of the access network and any connections of that access network at the OAP.
Figure 8 indicates that the interface at the SI is a defined optical fibre connector interface. The interface at the ADP may be either an unterminated optical fibre or, it testing in accordance with EN 61280-4-2 is required, an optical fibre terminated with appropriate connecting hardware.
5.8 Dimensioning and configuring
5.8.1 Premises dimensions
In order to meet the performance requirements of 6.3 (Table 2), the maximum length of cabling from the ADP to the SI shall not exceed 500 m.
Any premises requiring longer cabling lengths will increase the attenuation of the POAN cabling. Such configurations should not be pre-cabled without agreement with the access provider and may involve premises-specific implementations.
5.8.2 Distributors
The number and type of subsystems that are included in the PDAN cabling implementation depends upon the geography and size of the premises (e.g. campus or building) and upon the strategy of the premises owner.
A minimum implementation would include one PD, one SD per building. and one SI per subscriber.BS/EN 50700-2014 pdf download.