The Standard is also designed to provide architects with
guidance on the design of cabling systems for implementation
in buildings where user requirements can not be foreseen i.e.
in the initial planning either for construction or refurbishment.
In addition, it provides the industry with a cabling system
which will support current active equipment and provides a
basis for future developments.
ISO/IEC 11801:2000 specifies cabling for use within commercial
premises which may comprise of single or multiple buildings
on a campus. It covers balanced copper cabling and optical
fiber cabling. The principles of this standard may be applied
to installations that do not fall within this range.
Cabling defined by this standard supports a wide range of
services including voice, data, text, image and video.
conformance requirements and verification procedures.
Cables and cords used to connect application specific
equipment to the generic cabling system are outside of
the scope of this standard. Since they have significant
effect on transmission characteristics of the channel,
assumptions and guidance are provided on their performance
and length. Safety and electromagnetic compatibility (EMC)
requirements are outside the scope of this standard and
are covered by other standards and regulations. However,
information given in this standard may be of assistance
in meeting these standards and regulations.
Conformance
For a cabling installation to conform to this standard,
the configuration shall conform to the following;
Generic cabling schemes consist of three cabling sub
systems: Campus Backbone, building backbone and horizontal
cabling. This overview will deal with the horizontal element
only, although it will take into due consideration, the
other elements. The cabling subsystems are connected together
to create a generic cabling structure (as shown above).
The distributors provide the means to configure the cabling
to support different topologies like bus (ISDN), star
(Ethernet) and ring (Token Ring).
Campus Backbone Cabling Subsystem
The campus backbone cabling subsystem extends from the
campus distributor to the building distributor, usually
located in separate buildings. When present it includes
the campus backbone cables, the mechanical termination
of the backbone cables and the cross connections at the
distributor. The campus backbone may also interconnect
building distributors.
Building Backbone Cabling Subsystem
A building backbone cabling subsystem extends from building
distributor(s) to floor distributor(s). The subsystem
includes the building backbone cables, the mechanical
termination of the backbone cables and the cross connections
at the building distributor. the building backbone cables
shall not contain transition points and copper cables
should not contain splices.
Horizontal Cabling Subsystem
The horizontal cabling subsystem extends from a floor
distributor to the telecommunications outlet(s) connected
to it. The subsystem includes the horizontal cables, the
mechanical termination of the horizontal cables and the
floor distributor, the cross-connections at the floor
distributor and the telecommunications outlets.
Horizontal cables should be continuous from the floor
distributor to the telecommunications outlets. If necessary,
one transition point is permitted between a floor distributor
and any telecommunications outlet. The transmission characteristics
of the horizontal cabling shall be maintained. The consolidation
point shall not be used as a point of administration (i.e.
not used as a cross-connect). and active equipment shall
not be located there.
Work Area Cabling
The work area cabling connects the telecommunications
outlet to the terminal equipment. It is non-permanent
and application-specific and therefore lies outside of
the scope of ISO/IEC 11801.
Telecommunications Outlet
Telecommunications outlets are normally located on the
wall, floor or elsewhere in the work area. Telecommunications
outlets may be presented singly, or in groups, but each
individual work area shall be served by a minimum of two.
Telecommunications outlets shall be marked with a permanent
label that is visible to the user. Pair re-assignment
shall be done by means of external adaptors.
Telecommunications Closets and Equipment
Rooms
A telecommunications closet should provide all the faculties
(space, power, environmental control etc.) for passive
components, active devices, and public network interfaces
housed within it. Each telecommunications closet should
have direct access to the backbone.
Link Performance
Components and cables are defined as categories, however,
the link is defined a falling into one of four classes.
The standard divides installed copper links:
Class A -
|
Includes speech band and low frequency applications.
Copper cabling links supporting Class A applications
are specified up to 100KHz. |
Class B -
|
Includes medium bit rate data applications. Copper
cabling links supporting Class B applications are
specified up to 1MHz. |
Class C -
|
Includes high bit rate data applications. Copper
links supporting Class C applications are specified
up to 16MHz. |
Class D -
|
Includes very high bit rate data applications. Copper
links supporting Class D applications are specified
up to 100MHz. |
Class E -
|
Future applications. Copper links supporting Class
E applications are specified up to 250MHz.* |
Class F -
|
Future applications. Copper links supporting Class
F applications are specified up to 600MHz.* |
For copper cabling links, link classes A to D are specified
such that they will provide the minimum transmission performance.