ISO/IEC 11801-1 :2017 pdf download – Information technology – Generic cabling for customer premises – Part 1: General requirements.
5.3.4 Tie cabling Tie cables providing direct peer-to-peer connections between distributors are optional and, when provided, shall be in addition to that required for the basic hierarchical topology. When present, the tie cabling includes a) the tie cables, b) the jumper and patch cords at both distributors, c) the connecting hardware on which the tie cables are terminated (at both distributors). 5.3.5 Channel and permanent link The transmission performance of generic cabling is detailed in Clauses 6 and 7, in terms of the channel and the permanent link. The channel is the transmission path between equipment such as a LAN switch/hub (EQP in Figure 5) and the terminal equipment. A typical interconnect channel consists of cabling subsystem 1 together with the terminal equipment cord and equipment cord. A typical cross- connect channel consists of cabling subsystem 1 together with the terminal equipment cord, a patch cord or jumper, and equipment cord. Optional consolidation points may be used. For longer reach services the channel may be formed by the connection of two or more subsystems (including terminal equipment cords and equipment cords). The performance of the channel excludes the connections at the application-specific equipment. A permanent link is the transmission path of an installed cabling subsystem including the connecting hardware at the ends of the installed cable. In cabling subsystem 1 , the permanent link consists of the TE outlet, the optional consolidation point (if supported by the cabling design standard), subsystem cable 1 (or cables Y and Z of Figure 2, if a consolidation point is supported by the cable design standard and is present) and the termination of subsystem cable 1 at distributor 1 . The permanent link includes the connections at the ends of the installed cabling.
6 Channel performance requirements 6.1 General The performance of a channel is specified between connections to active equipment. The channel comprises only passive sections of cable, connecting hardware, terminal equipment cords, equipment cords and patch cords. The connections at the active equipment are not taken into account. The required transmission performance Class of Clause 6 shall be met for all environmental classifications specified for the channel. Application support depends on channel performance, which in turn depends on cable length, number of connections, and performance of the components within the environments to which the channel is subjected. It may be possible to achieve equivalent channel performance over greater lengths by the use of fewer connections or by using components with higher performance. 6.2 Environmental performance 6.2.1 General The environmental performance specifications of channels are classified to cover the different conditions under which channels are required to operate. The environmental classification described in 6.2.2 shall be used for the selection of components and/or the protection afforded to them. It is possible for the different locations within a channel to be subject to different environments. For example, one end of a channel can be in an office area and the other end of the channel can be subjected to a more severe environment. The description of the channel environment shall be divided up accordingly.
The definition of a given classification includes the definition of lower classifications, i.e. channels designed to operate under environmental conditions defined by M 2 shall continue to operate under environmental conditions defined by M 1 . Channel environments may be classified by using any combination of the MICE scheme, e.g. M 1 I 2 C 3 E 1 . Care should be taken to accurately classify the channel environment in such a way as to allow the selection of suitable components. The criteria for the MICE classification are based on M x I x C x E x. , where “x” can equal 1 , 2 or 3 based on the severity of the environment. For example, a typical office space has a minimum requirement of M 1 I 1 C 1 E 1 . The environmental Classes are defined in Table 2. For each M, I, C or E group, the classification of a given environment is determined by the most demanding parameter within the M, I, C or E group. However, the selection of components shall be based on the specific demands of each of the parameters within the M, I, C or E group, which may be less demanding than the overall classification of the group.