Twisted pair cable

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As twisted pair , cable, twisted pair or cable with twisted pairs are referred to in the telecommunications, message transmission and computer technology cable types , in which the wires together in pairs twisted are. Wire pairs with different lay lengths and different directions of rotation can be stranded in a cable in order to minimize crosstalk between the wire pairs. Compared to cores routed in parallel, twisted wire pairs offer better protection against electrical and magnetic interference fields. By twisting the wire pairs, influences from external fields largely cancel each other out.

An electrically conductive screen , often made of aluminum foil and / or metal mesh or copper , offers additional protection against interfering external electromagnetic fields . Twisted pair cables without a shield are called Unshielded Twisted Pair (UTP) . TP cables with an aluminum foil as a shield are called F / UTP (Foiled Unshielded Twisted Pair). TP cables with a copper braid as a shield are called S / UTP (Shielded Unshielded Twisted Pair). There are also cables in which the wire pairs are again shielded from one another; these are z. B. with S / STP (Screened Shielded Twisted Pair) or S / FTP (Screened Foiled Twisted Pair) .

Twisted wire pairs are intended for symmetrical signal transmission , which is less sensitive to common-mode interference due to their common- mode rejection.

Cables with twisted wire pairs have long been used for signal and data transmission, in computer technology initially for the parallel interface of the printer, the so-called Centronics interface . Today, appropriate cables are used for all types of signal transmission, u. a. in network technology z. B. as Ethernet cable or for structured cabling or in fieldbus technology .

Line structure

Twisted wire pairs with color sequence according to 25- pair color code

Twisted pair wire pairs contain from two twisted together ( English twisted ) pairs ( English pair , pair ') of individual wires.


  • Core: is a plastic-insulated copper conductor, for installation / laying cables as a rigid core ( wire ) with a common diameter of 0.4 mm or 0.6 mm. The standard designation of a typical twisted pair cable is accordingly 4 × 2 × 0.4 or 4 × 2 × 0.6:
    • 4 → number of stranding elements;
    • 2 → number of cores per stranding element;
    • 0.6 → diameter of a wire in mm.
With flexible patch cables as stranded wire with a common cross-section of 0.27 to 0.33 mm². Often the thickness of the copper conductor is also given in AWG ( American Wire Gauge ) ; the usual sizes then range from AWG 27 to AWG 22 (the smaller the AWG number, the thicker the conductor).
  • Pair: Two wires are twisted into a pair, several wire pairs are stranded together in the cable .
  • Conductor bundle or core: refers to the (often four) pairs stranded together in the cable. If there is more than one wire pair, the lay lengths are selected differently in order to reduce spurious / crosstalk.
  • Cable sheath: surrounds the soul. Usually consists of plastic mesh and a smooth cover over it. The material used is often PVC or halogen-free material such as PE or aramid .
  • Screen: metallic covering of individual wire pairs and / or the core. The screen consists of metal foil, metallized plastic foil, wire mesh or combinations thereof.

In addition to the wire pairs, there can be other elements in the cable, such as B .:

  • Drain wire: as an electrical ground line .
  • Filler cores: made of plastic to fill voids between the pairs.
  • Separators: made of plastic to keep the pairs apart.
  • Plastic thread: (for example made of nylon ) between the overall screen and the cable jacket, with which the cable jacket can be easily removed. To do this, hold the thread with pliers and pull it back at an acute angle. The thread cuts the envelope, which can now be easily removed.


If unshielded cables or connectors are used, there is no ground connection due to the isolating transformers used in the signal path between the power supply units . The screen promotes electromagnetic compatibility (EMC) and security against eavesdropping; Interactions with other devices are reduced. In the case of several ground connections between the devices connected in this way, however, a disruptive, mutual influence, the so-called ground loop , is possible precisely through the shield . It arises from voltage differences between the individual devices and causes equalizing currents in the ground, shield or PE connections, which can lead to interference. With many devices, the device ground is connected to the housing ground and, if there is a corresponding contact in the mains plug, also to the house earth, the PE conductor of the house installation. Special attention is then required here with regard to ground loops and an unshielded line can, despite the stronger radiation from outside interference, improve the transmission quality - even significantly.

An additional screen does not interfere with the protective mechanism of twisting, it also offers protection against common mode interference .

The shielding is used to improve immunity and suppress the emission of interference. In the case of a cabling section, the shield is placed on both sides of the respective components. The resulting equalizing currents counteract the magnetic field component of an electromagnetic wave according to the principle of Lenz's rule . 360 ° contacts are ideal. The shielding effect of a line is measured as transfer impedance .

Overview of the types of shielding
Twisted pair cable (TP) U / UTP S / UTP U / FTP S / FTP F / FTP SF / FTP
Overall screen Wire mesh (S) X X X
Foil (F) X X
Wire pair shield Wire mesh (S)
Foil (F) X X X X


Twisted-pair cables are available in two- and four-pair versions. For larger installations in cable ducts etc. Round cables with 50 pairs and more are also used. In current network installations, only four-pair cables are used in practice. Four-pair cables are mandatory for installations from Cat 6. In the cross-cable version, certain cable cores are swapped in one of the two RJ45 plugs .


Basic structure of a UTP cable
Basic structure of an STP, U / FTP, U / STP cable
Basic structure of an S / UTP cable
Basic structure of an S / FTP or F / FTP cable
F / UTP cable
S / FTP cable

Since the old designations are not uniform and are therefore often confusing or even contradictory, a new designation scheme of the form XX / YZZ was introduced in 2002 with the 2nd revision of ISO / IEC 11801 .

It says:

  • XX for the overall shield:
    • U = unshielded ( English unshielded )
    • F = foil screen ( English foiled )
    • S = braided screen ( English screened )
    • SF = braid and foil shield
  • Y stands for the wire pair shielding:
    • U = unshielded
    • F = foil screen
    • S = braided shield
  • ZZ stands for:
    • TP = twisted pair
    • QP = Quad Pair


Designation according to ISO / IEC 11801: U / UTP cable with unshielded pairs and without overall shield (Unshielded Twisted Pair). These are the most widely used cables for Ethernet LANs worldwide (more than 90 percent). A Category 5e UTP cable is sufficient for transmission methods up to Gigabit Ethernet. Shielded cables will only be required for future technologies (10 Gigabit Ethernet), but here too there will be a standard that works with UTP cables - even up to the standard cable length of 100 m.

Up to category 6, a UTP cable is easy to process due to its small outer diameter and the lack of shields and is usually cheaper than STP cable types. On the other hand, however, the clearances that must be maintained compared to live components and cables are significantly greater than would be necessary with shielded cables.

From category 6A (10 Gigabit Ethernet), UTP cables artificially create asymmetries in order to counteract alien crosstalk problems (Alien NEXT) when conductors run in parallel. As a result of this, the outer diameter has increased and is usually even larger than with S / FTP cables of category 7 and higher.


Outdated general term for cables with shielding ( Shielded Twisted Pair , also Twisted Pair Shielded - TPS ), without going into the type of shielding (wire mesh / foil); also imprecise and outdated designation for cables with wire braid shielding, without going into detail as to whether the shielding affects the individual pairs or the overall shielding.

In the following also part of the designation for cables with wire mesh as pair shield:

  • S / STP = s creened s hielded t wisted p air (with wire mesh as pair shield and as overall shield)
  • F / STP = f oiled s hielded t wisted p air (with wire mesh as pair shield and foil as overall shield)


Inaccurate and outdated designation for cables with foil shielding, without going into detail as to whether the shielding affects the individual pairs or the overall shielding.

New designation according to ISO / IEC -11801 (2002) E: F / UTP

The wire pairs are surrounded by a metallic screen (usually an aluminum- laminated plastic film) (foiled twisted pair). If one pair is shielded , one also speaks of PiMF ( P aar i n M etall f olie); includes the screen two pairs, it is also known as ViMF ( V ierer i n M etal f olie), respectively. The current version of EN50173-1 refers to these cables as FTP. Up to category 6, it was typically the case that, due to this additional shielding, the FTP cable had a slightly larger outer diameter than UTP cable and had slightly larger bending radii. (See notes from Category 6A for UTP cables). However, FTP cables are generally less sensitive and more efficient than UTP cables with regard to alien-next effects and lateral pressure. The shielding can also reduce crosstalk between the individual wire pairs (see also Electromagnetic Compatibility ).

S / UTP, F / UTP or SF / UTP

New designation according to ISO / IEC -11801 (2002) E: S / UTP (braid), F / UTP (foil), SF / UTP (braid + foil)

Structure as with UTP, but with additional metallic shielding around the conductor bundle (Screened Unshielded Twisted Pair). The overall shield can be designed as a foil or as a wire mesh or both together. According to the current EN50173, these cables are designated with an F for a foil shield, an S stands for a braided copper shield, and an SF stands for an overall shield made of foil and braid.

S / FTP, F / FTP or SF / FTP

New designation according to ISO / IEC -11801 (2002) E: S / FTP (braid), F / FTP (foil), SF / FTP (braid + foil)

Structure as with FTP, but with additional overall metallic shielding around the conductor bundle (Screened Foiled Twisted Pair). The overall shield can be designed as a foil or as a wire mesh or both together. According to the current EN50173, these cables are designated with an F for a foil shield, an S stands for a braided copper shield, and an SF stands for an overall shield made of foil and braid. The degree of coverage of the braid should be more than 30% in order to achieve adequate shielding against low-frequency fields.


An industrial cable variant (Industrial Twisted Pair) with S / STP cable structure. While typical network or patch cables have four wire pairs, ITP is limited to just two wire pairs.

WARP technique

The Swiss company R&M ( Reichle & De-Massari ) has launched a cable structure for 10 Gbit / s Ethernet with which cable lengths of over 100 m can also be achieved . The advantages of shielded and unshielded cables are combined. WARP stands for " Wave Reduction Patterns " - the wire pairs are shielded with metal foil segments approximately 1 ... 2 cm long. In contrast to conventional shielding, the foil segments are not electrically connected to one another and are not at ground potential, i.e. they are potential-free. The shielding offers significantly improved protection against near-end crosstalk (AXT).

The interrupted shielding improves the crosstalk behavior of symmetrical signal transmission of a twisted pair of wires without having to be connected or grounded. There is no need to carry a bare wire. The radial heat dissipation is still better than with unshielded cables, which is important with Power over Ethernet .


In order to describe the performance of an individual component, the individual components of a link (channel), which typically consists of connection components , cables and patch cables, are divided into categories and classes by ISO / IEC 11801 and EN 50173 . In a link, the component with the lowest performance (category) determines the transmission class (link class) of the entire system. Higher categories automatically cover the categories below. The interconnection of z. B. a Cat-5 cable with Cat-6 connection components reduces the link class from theoretical class E to class D.

To make it easier to classify the individual cables, categories have been defined that each correspond to a specific requirement profile. Categories 1 and 2 are only defined informally; Categories 3 and 4 are no longer commercially relevant (but can be found in old installations). The following are the defined categories:

Category 1

Cat-1 cables are designed for maximum operating frequencies of up to a few hundred kilohertz and are therefore unsuitable for Ethernet data transmission. They are used for voice transmission, for example in telephone applications. Only available as UTP cable.

Category 2

Cat-2 cables are suitable for maximum frequencies up to 1 or 4 MHz; they are used, for example, for house cabling for an ISDN primary rate connection .

Category 3

Cat 3 cables are unshielded twisted pair cables that are designed for a maximum operating frequency of 16 MHz. It's a type commonly misplaced in the United States. In America, Cat 3 was the standard cable type for all telephone wiring for a long time. Cat-3 cables have a lay length of three turns per foot for each twisted pair of copper conductors. Another property is that the lines are insulated with plastic ( Perfluor , FEP).

The cables are suitable for ISDN . 10 Mbit / s Ethernet (10BASE-T) can be operated on Cat 3 cables without any problems, and the 100BASE-T4 standard was also developed. It enables 100 Mbit / s on existing Category 3 installations, whereby four wire pairs are used. 100BASE-T4 has virtually no distribution outside of North America.

Category 4

20 MHz can be transmitted over Cat 4 cables . They are a common type in the United States. It offered little improvement in speed compared to Cat 3 and was generally ignored in favor of Cat 5.

Category 5 / 5e

20 m patch cable

Cat-5 cables are the predominant installed base today; they are used for signal transmission with high data transmission rates . The specific standard designation is EIA / TIA-568 . Cat-5 cables are designed for operating frequencies up to 100 MHz. Because of the high signal frequencies, particular care must be taken when laying and assembling, especially at the connection points of the wires. A minimum radius of curvature (specified in the data sheet) must not be undercut.

Cat 5 cables are often used for the structured cabling of computer networks , e.g. B. for Fast or Gigabit Ethernet. This promoted the spread of 1000BASE-T (Gigabit Ethernet), since only a Cat-5e cable is required here.

The introduction of 1000BASE-T (Gigabit Ethernet) and the associated signal transmission over all eight wires instead of only four wires as was previously the case with 10BASE-T and 100BASE-TX made it necessary to take additional values ​​such as PowerSum NEXT etc. into account. Components that met the new requirements and were therefore suitable for Gigabit Ethernet were marked as Cat 5e until the revision of the ISO11801 and EN50173 standards . Cat-5e cables are backwards compatible with conventional Cat-5 cables. With the new version of the 2002/2003 standards, Cat 5e disappeared as a designation and has been called Cat 5 again since then. Installations that were carried out before 2002 and that corresponded to Cat 5 at the time do not necessarily have to be Gigabit Ethernet compatible, and the cables should be checked with special measuring devices before use. The properties of cables labeled “Cat 5” cannot be determined if the date of manufacture is not known.

The designations EIA / TIA-568A and EIA / TIA-568B are also used informally to denote the two assignments of the color-coded wire pairs to the connection contacts of the RJ-45 connector as defined in this standard ; In this case, however, that does not say anything about the transmission quality.

Cat 5 and Cat 5e cables will still be available in 2020.

Category 6 / 6a / 6e

The Cat 6 cable is defined by EN50288. Cat 6 cables are designed for operating frequencies up to 250 MHz. The transmission speed suffers with longer lengths, but small excess lengths are harmless depending on external influences. Ultimately, security is provided by checking with a corresponding test device that verifies compliance with the limit values ​​of the current EN50173-1, IS 11801, or EIA / TIA 568B2.1.

Applications for Cat 6 are voice and data transmission as well as multimedia and ATM networks. Cables according to Cat 6A (500 MHz) according to EIA / TIA 568B2.1 Appendix 10d are more powerful. In the standardization phase of 10GBASE-T, a new Cat 6 specification with a bandwidth of 625 MHz was planned, as there is a transmission mode of 10GBASE-T (IEEE 802.3an, adopted in 2006) that supports this. However, this is currently not being pursued any further as it would have required new connector types compared to Cat 6a. The terms Cat 6 enhanced or Cat 6e can be found in some publications and sales catalogs , but this is not a standard; This is often used to ensure that a product is suitable for 10GBASE-T over at least 55 m.

Category 6 A / 6A

Cat 6 A module

Category 6 augmented (Cat 6 A or Cat 6A) is a standard that results from the increased bandwidth requirements of 10 Gigabit Ethernet (10GBASE-T), designed for transmission frequencies of up to 500 MHz and distances of up to 100 m and is downward compatible with existing categories is. Cat 6 A was defined by the international standardization body ISO / IEC (International Organization for Standardization / International Electrotechnical Commission) and Cat 6A by the US American EIA / TIA ( Electronic Industries Alliance / Telecommunications Industry Association ). The Cat 6 augmented demands higher technical conditions for the suppression of side signal effects and noise. The designation Category 6 A or Cat 6 A according to the international standard ISO / IEC 11801 always designates a component and not the entire transmission path (channel), while Cat 6A can designate both component and channel.

As far as the requirements for the transmission path (channel) for 10 Gigabit Ethernet are concerned, there are two valid standards in Europe: on the one hand, the IEEE 802.3 standard from the IEEE (Institute of Electrical and Electronics Engineers), on the other hand, Class E A from ISO / IEC. The IEEE standard is not sufficient to fully describe the necessary requirements for the cabling infrastructure, as it defines fewer criteria than the ISO / IEC standard. Therefore, for a comparison between the two variants of Category 6 augmented, only the ISO / IEC standard can be used as a counterpart to that of the EIA / TIA.

In the American standard EIA / TIA 568, the standard for the components according to Cat 6A and the transmission link according to Cat 6A has been adopted since the beginning of 2008, but has lower performance requirements than the worldwide ISO / IEC 11801. If you want to ensure the highest power reserve for channels and components, the ISO / IEC standards must be applied (Class E A for channels, Cat 6 A for components).

The requirements for the component in accordance with ISO / IEC Category 6 A were published in 2010 within the ISO / IEC 11801 working group in Appendix 2 (Amendment 2). To distinguish from the lower performance EIA / TIA-568B standard, the transmission path instead Cat 6A Class E is in the ISO / IEC A called and the component characterized by a subscript of A - Component Category 6 A .

Since the term Cat 6a is not protected, it can also be used within product names. The same was true for Cat 6e or Cat 7e. If the "a" is written in lower case, it does not indicate an official standard. The capitalized, simultaneous "A" designates the US standard with the lower requirements, the capitalized, subscript "A" the stricter European standard. Whether it is actually a category 6 augmented component can be determined, for example, by an independent testing institute using the measurement method direct probing or re-embedded according to the limit values ​​of the respective standards, such as EIA / TIA or ISO11801: 2002-Amd2 (Draft see above) to ensure. A corresponding test certificate gives the user the assurance that he is actually receiving a category 6 augmented component. The lower performance is noticeable less on long distances, as is often used in link certificates, but rather on short distances of up to 15 m, since the compensating effect of the cable does not really come into play here. This can also be the case for link lengths greater than 15 m, e.g. B. instead of a Category 7 cable, only a Category 6 A cable is used.

With a transmission path of class E A , based on ISO / IEC tested category 6 A components, you achieve a uniform, consistent performance of the entire cabling route and better protection for signal transmission up to 500 MHz, which is used with 10 Gigabit Ethernet comes. The ISO / IEC standard (components: Cat 6 A , Channel: Class E A ) thus offers the user more reserves and higher operational reliability.

Category 7/7 A

Global standard except in the USA (as of 2018). Category 7 (class F) enables operating frequencies up to 600 MHz, category 7 A (class FA) up to 1000 MHz.

Cat 7 cables have four individually shielded wire pairs (screened / foiled shielded twisted pair S / FTP) within a common shield. A Cat 7 cable meets the requirements of the IEEE 802.3an standard and is therefore suitable for 10 Gigabit Ethernet.

Example Cat-7 connector of type TERA

When the Cat 7 standard was drawn up in 2002 to enable 10 Gigabit Ethernet over 100 m, it was assumed that an operating frequency of 600 MHz was necessary. Since the RJ-45 plug cannot meet these specifications due to the close contact arrangement, new plug connections were designed that essentially increase the distance between the wire pairs.

During the standardization phase for ISO / IEC11802: 2002 and EN50173, various connector types were offered. The decision was made in favor of two different plug / socket types, which today are defined as the only approved category 7/7 A connection components.

  • Nexans GG45 (according to the standard to be preferred for office cabling due to its downward compatibility with RJ-45)
  • Siemon TERA (preferred according to the standard for multimedia applications)

The components have not been standardized

These connector types did not gain acceptance on the market, however, because RJ-45 was just as sufficient for the 10GBASE-T standard passed in 2006 as the category 6 A cables , so that the 10GBASE-T terminals that are common today can be connected to RJ-45 45 based. The network cabling frequently used for this purpose, consisting of Cat 7 cables and Cat 6 network sockets / patch panels, meets the speed standard, but the performance of the entire network route decreases regardless of the "good" Cat 7 cable in relation to the operating frequency at class E or E A level (Cat 6).

Only with the planned Category 8.2 standard and more than 40 Gbit / s data transmission rate could the new connector types become relevant again.

Category 8

Category 8 (Class G) cabling was adopted in November 2016 in the ANSI / TIA-568-C.2-1 standard.

Cat-8 cables are four-pair, shielded, symmetrical copper cables that would be suitable for 40 Gigabit Ethernet (40GBASE-T). Unshielded cables are no longer suitable for this bandwidth. There will be several Cat 8 standards, with the ANSI / TIA standard based on existing Cat 6A cables (F / UTP) and components and the ISO / IEC standard on existing Cat 7 A cables (S / FTP ) and components. Because of the resulting differences, a distinction will be made in future between Cat 8 (ANSI / TIA), Cat 8.1 (ISO / IEC) and Cat 8.2 (ISO / IEC), with Cat 8.1 being roughly equivalent to the ANSI / TIA standard of Cat 8.

Compared to fiber optic cables, copper has the significant advantages that, on the one hand, the overall costs are lower, on the other hand, handling is easier, and it is also capable of PoE (Power over Ethernet). The bandwidth of the Cat-8 cables is forecast between 1600 and 2000 MHz.

Cat 8 (ANSI / TIA) and Cat 8.1 (ISO / IEC) rely on the proven RJ-45 connector for the transmission of "Class G" in the future. However, these have increased demands on the compensation and present the developers with challenges that have yet to be solved. There are currently no published or available RJ-45 components for these two standards. For category 8.2 (ISO / IEC) there are already available connector faces based on class FA, but which are not RJ-45 plugs (see category 7 / 7A). In general, the maximum link length for "Class G" in the channel is limited to 30 m according to the IEEE specifications. Due to the use of S / FTP cables and not RJ-45 components for classes F and F A or frequencies greater than 500 MHz, which is already common in Germany , the VDE has already decided on an application rule within the meaning of VDE 0022 and in favor of the Use of category 8.2 pronounced.

Common twisted pair cable types (overview)

category class Type Bandwidth Applications Remarks standard
Cat 1 A. UTP 0.4 MHz Telephone and modem lines Not suitable for current systems. Not mentioned in any EIA / TIA recommendations
Cat 2 B. 4 MHz older terminal systems, e.g. B. IBM 3270
Cat 3 C. 16 MHz 10BASE-T and 100BASE-T4 Not suitable for speeds over 16 Mbit / s. Mainly used today as a telephone cable. described in EIA / TIA-568
Cat 4 20 MHz 16 Mbit / s token ring hardly used anymore.
Cat 5 D. 100 MHz 100BASE-TX Still used in LANs.
Cat 5e D. 100 MHz 1000BASE-T, 2.5GBASE-T and 5GBASE-T @ <75m Improved Cat 5, almost identical, but reduced crosstalk. The standard installation cable for a long time.
Cat 6 E. 250 MHz 5GBASE-T and 10GBASE-T @ <55m widespread SFS-EN 50173-1
Cat 6A E A STP 500 MHz 10GBASE-T The American standard Cat 6A is less stringent than the European standard Cat 6 A . Cat 6A is not an official standard. ISO / IEC 11801: 2002 Amendment 2
Cat 7 F. S / FTP 600 MHz CCTV four individually shielded wire pairs (screened / foiled
shielded twisted pair S / FTP) within a common shield
ISO / IEC 11801, 2nd edition
Cat 7a Q A 1000 MHz ISO / IEC 11801, 2nd edition, supplement 2
Cat 8 G 2000 MHz 25GBASE-T and 40GBASE-T IEC 46C / 976 / NP and ISO / IEC TR 11801-99-1 (planned)

The categories correspond to EIA / TIA-568A-5 (without Cat 7), classes are defined in ISO / IEC 11801: 2002 or EN 50173-1: 2002.

Visualization from Cat 3 to Cat 6A


In order for a cable to be certified according to one of the aforementioned categories, it must meet certain requirements. For example, for a Cat 6 certificate, the following points must be fully met:

Wiremap Check the correct wiring
Wave impedance Wave impedance of the cable
damping Decrease in amplitude
length Length of the transmission path
DC resistance Ohmic resistance
NEXT (near end crosstalk) near end crosstalk
FEXT (far end crosstalk) Far end crosstalk
ELFEXT (equal level far end crosstalk) Ratio of the crosstalk output level to the actual output level
ACR (Attenuation To Crosstalk Ratio) Attenuation to crosstalk ratio
powersum NEXT Power sum of near crosstalk
powersum ELFEXT Total power of the electromagnetic coupling at the remote cable end
powersum ACR Power sum of the attenuation-crosstalk ratio
Return loss Return loss , return loss
NVP (nominal velocity of propagation) delayed signal propagation time compared to the speed of light in a vacuum
Propagation delay Signal delay, group delay
Delay Skew Signal transit time difference on different wire pairs

measuring technology

Network analyzers from high frequency technology are used to measure the transmission behavior . A simple network analyzer with only two measuring ports only measures S-parameters . Four-port analyzers are particularly suitable for measuring twisted pair lines, as they can measure the M parameters directly. The transfer function as well as the reflection behavior and the mode conversion of the common and push-pull waves can be represented directly by means of the M parameters . The group delay and the associated distortions are also obtained from these measurements.


  • Klaus Dembowski: Local Networks. Manual of the complete network technology. Addison-Wesley Verlag, Munich 2007, ISBN 978-3-8273-2573-0 .
  • Alfred Olbrich: Networks - Protocols - Specifications. The basics for successful practice, 1st edition, Friedrich Vieweg & Sohn Verlag, Wiesbaden 2003, ISBN 3-528-05846-3 .
  • Joachim Böhringer, Peter Bühler, Patrick Schlaich: Compendium of media design for digital and print media. 3rd edition, Springer Verlag, Berlin / Heidelberg 2006, ISBN 978-3-540-242581 .
  • Christian Baun: Compact computer networks. 3rd edition, Springer Verlag, Berlin / Heidelberg 2015, ISBN 978-3-662-46931-6 .
  • Christoph Meinel, Harald Sack: Internetworking. Technical basics and applications, Springer Verlag, Berlin Heidelberg 2012, ISBN 978-3-540-92939-0 .
  • Herbert Bernstein: Information and communication electronics . De Gruyter Verlag, Oldenburg 2015, ISBN 978-3-11-036029-5 .

See also

Web links

Individual evidence

  1. ^ A b Information technology — Generic cabling for customer premises . ISO / IEC 11801: 2002
  2. web site R&M on WARP, accessed on May 29, 2018
  3. Twisted pair cable. (No longer available online.) Sdbj, p. 9 , formerly in the original ; Retrieved August 19, 2009 .  ( Page no longer available , search in web archivesInfo: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.@1@ 2Template: Dead Link /  
  6. ( Memento of the original from June 22, 2015 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot /
  7. ^ CCNA: Network Media Types . Retrieved October 22, 2013.
  8. Holger Heuer Men: high-frequency technology: components for high-speed and high frequency circuits . 2nd Edition. Vieweg + Teubner-Verlag, Wiesbaden 2009, ISBN 978-3-8348-0769-4 .