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ISO/IEC 11801

International standardization activities for application-neutral cabling systems began in 1991. The first draft of the international standard ISO/IEC 11801 was available in 1993 and published as early as 1995. The 11801 standard and the largely identical European standardEN 50173 are relevant for Germany. They define a scope for a site extension of up to 3 km and for an office area of up to 1 million square meters with 50 to 50,000 terminals. The standards support voice, data, text, image and video applications and therefore contain the specifications for configuration, implementation, performance and conformity. In addition, they describe recommendations for the general structure of a cabling system and classify the cable types to be used as well as the end-to-end connections ( link class


Scope and topologies of the 11801

standard Anessential component of the c

abling standards is a hierarchical structure with star-shaped cabling. The geographical scope is structured into primary c

abling, secondary c

ablingand tertiary

cabling.The structuring and the star-shaped structure of the cabling have several advantages: New network segments can easily be added without affecting the entire structure. If faults occur in one network segment, they remain limited to this network segment and do not affect the functionality of other subnetworks. Redundancy links can be provided against the failure of a primary link. The failure of a backbone network does not affect the communication functions within the subnetworks. In the tertiary areas, different network topologies - star, bus

, ring - can be implemented by appropriate wiring of the distributors.

Functional components of the cabling standard

structure according to ISO/IEC 11801

structure according to ISO/IEC 11801

The functional elements of the cabling areas include the primary cables and the site distributor

(SV) in the site


, thesecondary cables

and thebuilding


in thebuilding

cabling and thetertiary cables,


distributors (EV), any cabledistributors

(KV) and the telecommunications connection boxes (TA

) in thefloor

cabling.The cable lengths for the primary area were specified as 1,500 m, for the secondary area as 500 m, and for the tertiary area as 90 m.

Thedefinition range for the link classes ends at the telecommunications connection box; the connection cable up to 10 m long is not taken into account, only the range from the patch panel to the crossconnect

is taken into account in the link class

Transmission media specified in the 11801 standard

Scope of the universal cabling system

Scope of the universal cabling system

The standards are limited in the transmission media that can be used to optical fib

ersand symmetrical TP


Whereby the recommendations for all cabling ranges exempt both alternatives: Gradient fiber with 62.5/125 ┬Ám and UTP or STP cable. For the cable specifications, the standards define the three categories 3, 4 and 5. The transmission characteristics for these cables, as well as for the connection technology, are specified in so-called link classes, which are identified with the word Class

followed by a letter "A", "B", "C", "D", "E" or "F". Class "D", for example, has a transmission behaviour that is given by the properties of the transmission components of category 5, class "F" is based on components of category 7. For theclassification of

the cables, as for the link classes, there are proposals from DIN

, with which thefrequency range of the cables and the transmission properties of the link classes are to be extended. With categories 6 and 7, which were introduced into the international standard as German draft standard E DIN 44312-5, the frequency range is extended from 100 MHz

to 250 MHz (cat.6) and 600 MHz (cat.7), the corresponding link classes are called class E and F. Thenetwork application classes E and F support ATM, Gigabit Ethernet and 10 Gigabit Ethernet


In order to achieve future security and a high level of investment protection, the draft is downward compatible with the European standard EN 50173.

Components in the workstation area

In terms of connection components, the standards for fibre optic cables

provide for theSC

connectorand the much more compact LC

connector,which is to replace the SC connector. For the twisted copper cables, only

theRJ45 connector

is recommended in the distribution area as well as in theworkstation cabling. However, the RJ45 plug can only be used to a limited extent for higher bandwidths, corresponding to category 7, since it only achieves the required NEXT values when the outer connection pairs are wired. Since this would have led to a restriction of flexibility, the GG-45 connector and the TERA connector

were approved for cabling in accordance with link class F. The IEC and ISO approved the RJ45 connector. The GG-45 connector has been standardized by the IEC and ISO.

Definition of link, permanent link and channel

Definition of link, permanent link and channel

Further changes affect the tertiary area. This area consists of the route from the transmission device to the crossconnect, the patch field with patch cable, the horizontal cabling (90 m) with the Tk junction box and the connecting cable to the terminal device. In the link specification of the 1st version, the distribution area and the floor cable were considered, but not the connecting cable. In the revision of the standard, the Link specification is replaced by the "Permanent Link" and the "Channel". The Permanent Link is the area between the patch panel and the telecommunications junction box, and the Channel defines the end-to-end connection in the tertiary area between the transmission device and the terminal. Thus, the channel specification takes into account all components and cables of the floor cabling: The cross connect with distribution cable, the patch panel with patch cable, the floor cable, the junction box

and the connecting cable. The standards define all cable specifications such as the characteristicimpedance, attenuation, near-end c

rosstalk(NEXT) and attenuation-to-crosstalk ratio (ACR), as well as the transmission characteristics of the connectors

.In 2018, the ISO/IEC 11801 standard was updated, expanded and restructured.

According to this, there is the following structure: 11801-1: General, 11801-2: Office buildings, 11801-3: Industrial, 11801-4: Residential, 11801-5: Data centers and 11801-6: Building automation.

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Englisch: ISO/IEC 11801
Updated at: 11.10.2018
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