Various cables are used for carrying Ethernet: current common types include Cat 5, 5e, Cat 6, 6a, 7 and Cat 8 and the RJ45 connector is widely usedEthernet IEEE 802.3 Includes: Show
There are many Ethernet cables that can be bought. Often these cables are supplied free with equipment that uses Ethernet connectivity in some way or another. There are several different varieties and categories of Ethernet cable that can be obtained: speed variations, crossover cables, Cat 5, Cat 5e, Cat6, Cat 6a, Cat 7etc.. Typical Ethernet cable supplied with many computers, routers, etcNormally Ethernet cables will be bought and there is no major need to understand what is inside or on the connectors, although it can be both interesting and helpful on some occasions. Even so, an understanding of the different types of Ethernet cable and the maximum lengths that should be used is helpful. The commonly used network cables: Cat 5, Cat 5e, Cat 6, Cat 6a, Cat7 all have different levels of performance, and therefore to is necessary to buy or select the right cable for the right application. These network cables are used for connecting a variety of network elements from Ethernet switches and Ethernet routers to computers, servers and other network items - if there is an Ethernet interface, they can be connected using Ethernet cables. In fact Ethernet cables of all types form the backbone of virtually all local area networks regardless of the network topology used, and as such they are of immense importance and interest. Ethernet cable basicsThe Ethernet cables for connectivity in most office and home local area networks rely on twisted wire pairs within an overall cable - Cat 5, Cat 6 and Cat 7 all used this format. Twisting the wires together enables the currents to balance, i.e in one wire the current is moving in one direction, and in the other wire of the pair the current is going in the other, enabling the overall fields around the twisted pair to cancel. In this way, data can be transmitted over considerable lengths without the need for undue precautions. As several twisted pairs are contained within a particular data network cable, the number of twisted per unit length is arranged to be different for each pair - the rate being based on prime numbers so that no two twists ever align. This reduces crosstalk within the cable. The Ethernet cables are available in a variety of lengths as patch cables, or the cable itself is available for incorporating into systems, buildings, etc. The terminations can then be made to the required connector using a crimp tool. These network cables are available in a variety of lengths - long Ethernet cables are available, some of the longest being up to 75 metres. Earlier network cables were unshielded, but later ones were shielded to improve the performance. For example an unshielded twisted pair, UTP, cable may be satisfactory for a short run between a computer and router, but a foil shielded cable, FTP, is best longer runs or where the cable passes through areas of high electrical noise. Flat Ethernet cable and connectorThere are different methods that can be used for shielding Ethernet cables. The most common is to place a shield around each twisted pair. This not only provides shielding for the cable externally, but also reduces crosstalk between the internal twisted pairs as well. Manufacturers can further enhance the performance by placing shielding around all the wires in the cable just under the cable sheath. There are different codes used to indicate the differs types of shielding:
Where: TP = twisted pair, U = unshielded, F = foil shielded, S = braided shielding. A further difference within the Ethernet cables whether Cat 5, Cat 5e, Cat 6, Cat 6e, or Cat 7 can be whether solid or stranded wires are used within the cable. As the description implies, a solid cable uses a single piece of copper for the electrical conductor within each wire of the cable whilst stranded wire uses a series of copper strands twisted together. Although when buying a patch cable, it may not be necessary to know this, when installing a long cable run it may be important as each type is slightly more suitable for different applications.
Categories for Ethernet cablesA variety of different cables are available for Ethernet and other telecommunications and networking applications. These network cables that are described by their different Ethernet cable categories, e.g. Cat 5 cables, Cat 6 cables, Cat 7 and Cat 8etc, which are often recognised by the TIA (telecommunications Industries Association) and they are summarised below:
Further descriptions of Cat-5 and Cat-5e cables are given below as these are widely used for Ethernet networking applications today.
* 25 Gbps for Cat 8.1 and 40 Gbps for Cat 8.2. Ethernet cable connectorsThe RJ45, Registered Jack 45 connector is used almost universally as the physical connector used on Ethernet cables, and with networking cables in general. From Ethernet Category 3 right through to Cat 6, the RJ45 is the format that is used. Cat 7 Ethernet cables can be terminated with RJ45 connectors but specialised versions called GigaGate45 (GG45) are often used. Fortunately these are backwards compatible with the RJ45 so there is no need to have a completely new installation when migrating to Cat 7. Ethernet RJ45 connector on an Ethernet cableThe RJ45 connector used on the ends of Ethernet cables are small plastic plugs with a retaining catch that can be released when the cable needs to be removed. The term plug refers to the male end of the connection on the network cable, and the jack refers to the port or female and normally located on the equipment. The RJ45 connector has eight pins that are spaced around 1 mm apart, and the wires are inserted and crimped to provide a reliable connection. The actual connector type is known as an 8P8C - eight position - eight contact. Strictly speaking the actual connector type should be reared to as an 8P8C, and the wiring pattern is RJ45, but in reality the term RJ45 for Ethernet cables is used almost universally. Ethercon connectorsAlthough the RJ45 connector is ideal for most applications, it is not particularly robust. It is suitable for office, data-centre and home connections where robustness is not an issue. However there are a number of scenarios where a more robust connector is needed - applications like audio visual, stage audio and lighting, etc where Ethernet is used need a much more robust connection. To address this problem the Ethercon connector is used. The Ethercon connector can be likened to a combination of an RJ45 with an XLR connector. As the Ethercon connector has a circular metal outer protection combined with the RG45 style inner, it provides the required connectivity with the robustness required for applications like stage and other audio visual areas where Ethernet connections are required. It is possible not only to obtain the Ethercon connectors on their own, but also ready made Ethercon leads as well. Ethernet cable pinoutAlthough the wiring and the cable manufacture details may vary between the different cable categories, the basic connectivity remains the same. In this way Ethernet cables can be used reliably to make connections between items of equipment, etc. A summary of the signals carried and the relevant wires and connections is given in the table below:
In the table, TX is transmitted data, and RX is received data. BI_Dn is bi-directional data, A, B, C, and D. There are two standard RJ45 pinouts for the individual arrangement of the wire connections to the RJ45 connectors within an Ethernet cable: the T568A and T568B standards. One or other of the conventions should be followed, as this will ensure the required connectivity, although as it is just a colour convention and the same wires and pairs are connected to the same pins, it does not matter which one is followed. In practice T568B is the more commonly used, and therefore it is probably best to use this one. The standard used may also be indicated on the sheath of ready made Ethernet cables.
Ethernet Cat 5 crossover cablesThere are a number of different configurations of cable that may be employed according to the equipment and the requirement. The most common type are the straight through cables which are wired in a 1 to 1 configuration. However Cat-5 crossover cables are also required on occasions. Typically a Cat-5 cable used to connect a computer (PC) to a switch will be a straight through cable. However if two computers or two switches are connected together then a Cat5 crossover cable is used. Many Ethernet interfaces in use today are able to detect the type of cable, whether it is a straight through or crossover cable, and they are able to adapt to the required format. This means that the requirement for Cat-5 crossover cables is less than it might otherwise be. When using Cat-5 Ethernet crossover cables, they are not marked with the fact that they are crossover cables. Accordingly it is often wise to mark them to avoid confusion later. Ethernet cable maximum lengthsOften it is necessary to use long Ethernet cables, however there are limits to the distance over which the data can be reliably carried. When long Ethernet cables are used, additional noise is picked up, and the data eventually becomes distorted by the cable. A summary of Ethernet cables and their maximum operating lengths is given below:
Lengths provided are those generally accepted as the maximum, but are not included in the IEEE standard. A variety of different cables of different types and Ethernet cable categories are seen connecting different Ethernet elements together - Ethernet routers, Ethernet switches, computers, network severs, etc. Cat5, Cat5e and Cat6 are all seen. These are often within a local area network of one form or another. The cables use the cost efficient but effective RJ45 patch connector and using this, these Ethernet cables are able to link or patch multiple items of Ethernet based equipment together. On some occasions where specialised connectivity is needed crossover cables may be required - these sold be clearly marked as such as they may get used elsewhere unknowingly and cause the connection not to work. Apart from this, using Cat 5, Cat5e, Cat 6, Cat 7 and now Cat 8 Ethernet cables is very easy and there are normally very few issues. Wireless
& Wired Connectivity Topics: What connector is used on Cat 5 cables?Cable types, connector types and cabling topologies are defined by ANSI/TIA-568. Nearly always, 8P8C modular connectors (often referred to incorrectly as RJ45 connectors) are used for connecting category 5 cable. The cable is terminated in either the T568A scheme or the T568B scheme.
Which wire pairs are used on a 100BaseT network?100BaseT networks, also called Fast Ethernet networks, use only two wire pairs: green and orange.
What pins are used in Ethernet cable?What pins does Ethernet use? An Ethernet cable RJ45 connector has 8 pins. Pins 1 & 2 (green) and pins 3 & 6 (orange) are used for data communications while pins 4 & 5 (blue) and pins 7 & 8 (brown) are not used.
Which tool is used to attach an RJ45 connector to a Cat 5 cable?An RJ45 crimping tool (sometimes called an RJ45 crimper or RJ45 connector tool) is used to attach the male plug connectors to the ends of a suitable cable.
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