Cabletron Systems Cabling Guide
Notice Notice Cabletron Systems reserves the right to make changes in specifications and other information contained in this document without prior notice. The reader should in all cases consult Cabletron Systems to determine whether any such changes have been made. The hardware, firmware, or software described in this manual is subject to change without notice.
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Contents Chapter 1 Introduction Using This Guide ......................................................................................................................... 1-1 Document Organization ............................................................................................................. 1-1 Document Conventions .............................................................................................................. 1-3 Warnings and Notifications ...................................
Chapter 5 Ethernet Network Requirements 10BASE-T ......................................................................................................................................5-1 Cable Type .............................................................................................................................5-1 Insertion Loss (Attenuation) ...............................................................................................5-1 Impedance .............................................
10BASE-F (Multimode)............................................................................................................... 6-4 Cable Type ............................................................................................................................. 6-4 Attenuation............................................................................................................................ 6-5 Insertion Loss ................................................................................
Chapter 8 Full-Duplex Fast Ethernet Network Requirements 100BASE-TX..................................................................................................................................8-1 Cable Type .............................................................................................................................8-1 Insertion Loss (Attenuation) ...............................................................................................8-2 Impedance ...............................
IEEE 802.5j (Multimode Fiber Optics) .................................................................................... 10-8 Cable Type ........................................................................................................................... 10-8 Attenuation.......................................................................................................................... 10-9 Link Length ..............................................................................................
Chapter 13 Cabling Devices Hardware Mounting..................................................................................................................13-2 Relay Rack ...........................................................................................................................13-2 Enclosed Equipment Cabinet............................................................................................13-3 Cable Termination....................................................................
Chapter 1 Introduction Using This Guide The Cabletron Systems Cabling Guide is intended to provide much of the information necessary to allow Network Managers to plan facility network cabling and to ensure that the cabling is usable by the networking devices that will populate the cabling. This Cabling Guide also provides instructions that may be helpful for connecting Cabletron Systems networking devices to an existing facility cabling infrastructure.
Introduction The following summarizes the organization of this manual: Chapter 1, Introduction, discusses the use and contents of this guide. Chapter 2, Cabling Terms, defines and explains some of the terminology used throughout this document to describe aspects and components of cabling and installation planning. Chapter 3, Relevant Specifications, details some relevant specifications and standards that apply to the installation of facility network cabling.
Introduction Appendix A, Charts and Tables, provides the information contained in the network requirements chapters of this document in a simplified table form. Tables of test requirements and acceptable levels are provided for all media discussed in this document. Following the appendix, the Cabletron Systems Glossary of Terms may be found. Document Conventions Warnings and Notifications NOTE Note symbol. Calls the reader’s attention to any item of information that may be of special importance.
Introduction Additional Assistance The planning and installation of facility cabling for network operation is a complex and highly specialized process. Due to the different nature of each and every cabling installation and the special problems and concerns raised by any facility, there may be aspects of installation planning that are not covered in this guide.
Chapter 2 Cabling Terms This chapter identifies and defines several terms that are used throughout the text of this manual. Physical Components The following terms and definitions deal with the physical makeup of cabling used in Local Area Networks. Media Media refers to a type or family of cables. When the term media is used, it indicates a type of cabling, rather than a specific cable.
Cabling Terms Jumper Cabling Jumper cabling is a term that identifies short, inexpensive cables that are used to make connections between nearby cabling devices. Typically, workstations and network devices are connected to the facility cabling of a site with jumper cables. Run A “run” of cabling is a single end-to-end cable path in a networked facility. The cable run typically begins at a network device such as a hub or bridge and ends at a workstation or other end node.
Cabling Terms Strand A strand is a metal or glass (in the case of fiber optics) transmission media that is typically surrounded by an insulator. Strands in metallic cables may be made up of either solid lengths of relatively thick wire (solid core) or a bundle of much thinner wires that contact one another throughout the wire (stranded).
Cabling Terms Housing (Shell) The basis of the connector is its housing. A housing is the metal or plastic parts that make up the shape of the connector and determine its characteristics and what ports or other connectors it may be attached to. The purpose of the housing is to separate and organize any strands in the cable being connected and arrange them in a standard fashion for connection to a port or other connector.
Cabling Terms Gender The gender of a connector refers to the organization of the pins, contacts, or channels of the connector. Connectors may be identified as male, female, hermaphroditic, or genderless. The most common types of connectors in networking are male and female. A male connector is one that is inserted into a recessed or hollow port. In the case of some connectors, the determination of male gender is based upon whether the connector makes its networking connection through a pin or a channel.
Cabling Terms Port A port is a set of pins or channels on a networking or cabling device that are arranged to accept a connector. Ports are constructed much like connectors, and will only accept the connector type they are specifically designed for. Ports may be keyed, gendered, or locking, in the same fashion as connectors. Jack A jack is a term that is usually synonymous with port, and indicates a port location. Typically, the term refers to ports located on wallplates or other passive cabling devices.
Cabling Terms Delay The term delay, when applied to network cabling, typically refers to the propagation delay of the segment or network. As signals in both electrically conductive cables and fiber optic cables travel through the transmission media at a fraction of the speed of light, there is an appreciable delay between the transmission of a signal on one end of a cable and the reception of the same signal on the other end. Network delay is typically measured in microseconds (µs).
Cabling Terms 2-8 Test Characteristics
Chapter 3 Relevant Specifications This chapter presents and examines a number of networking specifications and how they are related to planning and installing network cabling. Just as there are specifications that deal with the tested aspects of installed cabling and their fitness for use with a particular networking technology, there are also standards that deal with the construction of cables and the methods by which they may be installed.
Relevant Specifications The installation procedures of the EIA/TIA help to ensure that care is taken to avoid cabling situations that are possibly hazardous or which can result in degradation of the operating quality of the installed cable.
Chapter 4 Ethernet Media This chapter examines the physical characteristics and requirements of both physical cabling and the connectors and ports used with the cabling in Ethernet , Full-Duplex Ethernet, and Fast Ethernet environments. Cabling Types Attachment Unit Interface (AUI) Attachment Unit Interface cable (referred to hereafter as AUI cable) is a shielded, multistranded cable that is used to connect Ethernet network devices to Ethernet transceivers. AUI cable should be used for no other purpose.
Ethernet Media YES NO NO 1845n01 Figure 4-1. AUI Cable Configurations The reason for the configuration of AUI cables as Male to Female only is due to their intended use. AUI cables are designed to attach transceivers to workstations or other active network equipment. Transceivers require power to operate, and that power is supplied either by an external power supply or by a pair of wires dedicated to power in the cable.
Ethernet Media Office Office AUI cable is a thinner cable that is more convenient to use on many environments than standard AUI. This lighter-gauge AUI cable is made up of four pairs of AWG 28 wire, which is thinner (at 0.26 inch) and much more easily flexed, but can only be run to a maximum distance of 16.5 meters. Office AUI cable is intended to be used in places where standard AUI cable would be cumbersome and inflexible.
Ethernet Media Thick coaxial cable is a media used exclusively in Ethernet installations, commonly as a backbone media. Transceivers are connected to the cable at specified distances from one another, and standard transceiver cables connect these transceivers to the network devices. Due to the extensive shielding, thick coaxial cable is highly resistant to electrical interference by outside sources such as lighting, machinery, etc. Because of the bulkiness (typically 0.
Ethernet Media Building Network Coax (BNC) connectors crimp onto a properly prepared cable end with a crimping tool. To prevent signal reflection on the cable, 50 Ohm terminators are used on unconnected cable ends. As with thick coaxial cable, thin coaxial cable allows multiple devices to connect to a single cable. Up to 30 transceivers may be connected to a single length of thin coaxial cable, spaced a minimum of 0.5 meter from one another.
Ethernet Media Both the original and the inverted signal are then transmitted, the original signal over the TX+ wire, the inverted signal over the TX - wire. As these wires are the same length and of the same construction, the signal travels (propagates) at the same rate through the cable. Since the pairs are twisted together, any outside electrical interference that affects one member of the pair will have the same effect on the other member of that pair.
Ethernet Media The association of pairs of wire within the UTP cable jacket are decided by the specifications to which the cable is built. There are two main specifications in use around the world for the production of UTP cabling: EIA/TIA 568A and the EIA/TIA 568B. The two wiring standards are different from one another in the way that the wires are associated with one another at the connectors.
Ethernet Media Table 4-1. 10BASE-T/100BASE-TX Four-Pair Wire Use Ethernet Signal Use Wire Color EIA/TIA Pair 568A White/Blue (W-BL) Blue (BL) White/Orange (W-OR) Orange (OR) White/Green (W-GR) Green (GR) White/Brown (W-BR) Brown (BR) NOTE Pair 1 Pair 2 Pair 3 Pair 4 568B Not Used RX+ TX+ RX- TX- TX+ RX+ TX- RX- Not Used Do not split pairs in a twisted pair installation.
Ethernet Media As with four-pair cable, the wires within a 25-pair cable are identified by color. The jacket of each wire in a 25-pair cable has an overall color: violet, green, brown, blue, red, orange, yellow, gray, black, and white. In a 25-pair UTP cable all wires in the cable are identified by two colors. The first color is the base color of the insulator, while the second is the color of narrow bands painted onto the base color.
Ethernet Media Table 4-2.
Ethernet Media Table 4-2.
Ethernet Media Crossovers The 10BASE-T and 100BASE-TX specifications require that some UTP connections be crossed over. Crossing over is the reversal of the transmit and receive pairs at opposite ends of a single cable. Each cable that swaps the location of the transmit and receive pairs at only one end is called a crossover cable. Those cables that maintain the same pin numbers for transmit and receive pairs at both ends are called straight-through cables.
Ethernet Media UTP Cable Quality UTP cabling is produced in a number of overall quality levels, called Categories. The requirements of networking limit UTP cabling for Ethernet to Categories 3, 4, and 5. Any of these cable Categories can be used in an Ethernet installation, provided that the requisite IEEE 802.3 specifications regarding the cables are met. Category 3 UTP cabling that is built to the Category 3 specification consists of two or more pairs of solid 24 AWG copper strands.
Ethernet Media Category 5 UTP consists of 2 or more pairs of 22 or 24 AWG wire. Category 5 cable is constructed and insulated such that the maximum attenuation of a 10 MHz signal in a cable run at the control temperature of 20° C is 65 dB/km. A cable that has a maximum attenuation higher than 65 dB/km does not meet the Category 5 requirements. Fiber Optics Fiber optic cable is a high performance media constructed of glass or plastic that uses pulses of light as a transmission method.
Ethernet Media Fiber optics of both types are measured and identified by a variety of means. The usual means of referring to a fiber optic cable type is to identify if it is single mode or multimode, and to describe the thickness of each strand. Fiber optics are very thin, and the diameter of each strand is measured in microns (µm). Two measurements are important in fiber optic identification; the diameter of the core, where signals travel, and the diameter of the cladding, which surrounds the core.
Ethernet Media Single Mode Single mode fiber optics are designed specifically to allow the transmission of a very narrow range of wavelengths within the core of the fiber. As the precise wavelength control required to accomplish this is performed using lasers, which direct a single, narrow ray of light, the transmissive core of single mode fiber optics is typically very small (8 to 10 µm). Single mode fiber is more expensive to produce than multimode fiber, and is typically used in long-haul applications.
Ethernet Media Connector Types AUI AUI cabling is always connected with DB15 ports and connectors. The use of any other type of connector for AUI cable is a violation of the IEEE 802.3 specification and is considered nonstandard. DB15 The DB15 connector (male or female) provides 15 pins or channels (depending on gender). For identification, these pins are numbered from 1 to 15.
Ethernet Media Table 4-3.
Ethernet Media Coaxial Cable The connectors available for coaxial cabling are dependent upon the type of coaxial cabling in question. Thick coaxial cable may be tapped into without breaking the continuity of the cable or may be physically cut and re-connected. Thin coaxial cable cannot support the non-intrusive tap style, and must be split and connected to a junction device at each point where a connection is to be made.
Ethernet Media Thick coaxial cables require termination with N-Type connectors. As the coaxial cable carries network transmissions as voltage, both ends of the thick coaxial cable must be terminated with N-Type connectors and terminators to keep the signal from reflecting throughout the cable, which would disrupt network operation. The terminators used for thick coaxial cable are 50 Ohm (Ω) terminators.
Ethernet Media Coax Cable le add ble S Ca Contact Pin ER SCEIV TRAN 1845n11 AUI Connector (Female) Figure 4-11. Cable Saddle and Transceiver Assembly BNC The BNC connector, used in 10BASE2 environments, is an intrusive connector much like the N-Type connector used with thick coaxial cable (described above). The BNC connector (shown in Figure 4-12) requires that the coaxial cable be broken at an annular ring to make the connection.
Ethernet Media Key Guide Channel Locking Key Metal Casing Insulator Solid Center Strand Hollow Center Channel 1845n12 Figure 4-12. BNC connectors T-Connector Connections from the cable to network nodes are typically made using T-connectors, which provide taps for additional runs of coaxial cable to workstations or network devices.
Ethernet Media UTP Cable RJ45 The RJ45 connector is a modular, plastic connector that is often used in UTP cable installations. The RJ45 is a keyed connector, designed to be plugged into an RJ45 port only in the correct alignment. The connector is a plastic housing that is crimped onto a length of UTP cable using a custom RJ45 die tool. The connector housing is often transparent, and consists of a main body, the contact blades or “pins,” the raised key, and a locking clip and arm.
Ethernet Media Staggered Teeth Clamp Core Wire Solid Core Inline Teeth Nest in Core Strands Stranded Core Insulator Insulator 1845n15 Figure 4-15. Solid and Stranded RJ45 Blades The solid UTP connector arranges the contact points of the blades in a staggered fashion. The purpose of this arrangement is to pierce the insulator on either side of the core wire and make contacts on either side.
Ethernet Media The EIA/TIA 568B specification reverses the arrangement of Pair 1 and Pair 2, but does not change the association of pairs within the cable. The Universal Service Order Code, or USOC, a standard used for Token Ring network installations or some telephone wiring, uses a different pair association than EIA/TIA 568A. The USOC standard will cause a split pair condition in an IEEE 10BASE-T environment, causing a loss of network functionality.
Ethernet Media Receive 1 2 Transmit + 26 Receive 27 Transmit 1 26 2 27 3 28 4 29 5 30 6 31 7 32 8 33 9 34 10 35 11 36 12 37 13 38 14 39 15 40 16 41 17 42 18 43 19 44 20 45 21 46 22 47 23 48 24 49 25 50 1845n18 Figure 4-18. RJ21 Pinout Mapping for 10BASE-T Punchdown Blocks While not strictly a connector type, the punchdown block is a fairly common component in many Ethernet 10BASE-T installations that use 25-pair cable.
Ethernet Media A B C D 01 10 11 20 21 30 31 40 41 50 1845n19 Figure 4-19.
Ethernet Media Fiber Optics As both multimode and single mode fiber optics use the same standard connector in the Ethernet 10BASE-FL and FOIRL specifications, both cabling types are treated in the section that follows. The recommended connector for 100BASE-FX networks is discussed in the closing pages of this section. NOTE The 10BASE-F specification is broken up into three main categories; 10BASE-FP Passive Fiber Optic Star, 10BASE-FB Active Fiber Optic Backbone, and 10BASE-FL Active Fiber Optic Link.
Ethernet Media The key guide channels of the male ST connector allow the ST connector to only be connected to a female ST connector in the proper alignment. The alignment keys of the female ST connector ensure the proper rotation of the connector and, at the end of the channel, lock the male ST connector into place at the correct attitude. An integral spring helps to keep the ST connectors from being crushed together, damaging the fiber optic cables.
Ethernet Media 4-30 Connector Types
Chapter 5 Ethernet Network Requirements This chapter provides test parameters and specification requirements for Ethernet network cabling. 10BASE-T All Cabletron Systems 10BASE-T products require that installed facility cabling and cable hardware meet the following minimum specifications. If a network cabling installation is not within the limitations presented here, the operation of the 10BASE-T products may be affected.
Ethernet Network Requirements The insertion loss characteristics of a cable are one of the main determinants of link length allowed by the Ethernet and 10BASE-T specifications. As long as a UTP cable does not exceed the total insertion loss of 11.5 dB, it may be any length up to 200 m (656 ft). The 200 meter maximum total length is based on the total allowable propagation delay in the network, and cannot be exceeded.
Ethernet Network Requirements Crosstalk Crosstalk is electrical interference between wires. Crosstalk occurs when a cable strand absorbs signals from other wires that it is adjacent to. Excessive crosstalk can be caused by a break in the insulation or shielding that separates wires from one another in a bundle. Ethernet UTP cables should be checked for Near-End Crosstalk, or NEXT, at installation. The allowable amount of NEXT for a UTP cable is dependent upon the type of cable used in the installation.
Ethernet Network Requirements The IEEE 802.3 10BASE-T specification requires that all 10BASE-T devices support UTP cables of not less than 100 m (328 ft) in length. This requirement does not factor in losses due to connectors, patch panels, punchdown blocks, or other cable management hardware, which introduce additional loss. For each connector or other intrusive cable management device in the total link, subtract 12 m (39.4 ft) from the total allowable link length.
Ethernet Network Requirements Attenuation Multimode fiber optic cables must be tested for attenuation with a fiber optic attenuation test set. The test set must be configured to determine attenuation of the cable at a wavelength of 850 nm. The attenuation test will confirm or deny that the cable falls within an acceptable level. The acceptable level of attenuation for a cable is dependent upon the type of multimode fiber optic cable being tested.
Ethernet Network Requirements Length The 10BASE-F specification limits a multimode fiber optic cable segment to 2 km or less. Assuming that a fiber optic cable meets all other limitations for 10BASE-F usage, it is possible to extend a multimode fiber optic link to an absolute maximum of 2 km. At a length of more than 2 km, the propagation delay introduced by the multimode fiber optic cable segment may exceed the 25.6 µs limit of the Ethernet specification and cause excessive OOW errors.
Ethernet Network Requirements Insertion Loss The FOIRL specification allows for a total loss of 10 dB or less between any two stations or devices connected by fiber optic cabling. When calculating insertion loss, you must consider and count any loss introduced by fiber optic splices, barrel connectors, distribution boxes or other cable management devices. The typical dB loss for a splice or a connector is less than 1 dB.
Ethernet Network Requirements 10BASE2 All Cabletron Systems 10BASE2 products require that installed thin coaxial cables and related cabling hardware meet the following minimum specifications. If a network installation does not comply with the following specifications, operation of the 10BASE2 products may be affected. Cable Type Cabletron Systems 10BASE2 products are designed to be connected to 50 Ohm RG-58 A/U type coaxial cable.
Ethernet Network Requirements Grounding Each thin coaxial cable segment should be connected to earth ground at only one point. The connection to a ground should not be made through the BNC ports of a network device or T-connector unless the connection to the ground is made through the BNC terminator at the end of the cable. The grounding wire must be connected to the outer metal shield of the coaxial cable and should be no longer than 10 m (32.8 ft).
Ethernet Network Requirements Connectors/Taps 10BASE5 cables may be terminated with intrusive (N-Type) connectors or tapped by coring through the cable to the transmissive core wire. Termination of the cable segment must be accomplished with intrusive connectors. Connectors or taps on the 10BASE5 cable must be spaced no less than 2.5 m (8.2 ft) from one another or the cable termination. If connectors are located closer to one another than this minimum, a loss of network performance may result.
Chapter 6 Full-Duplex Ethernet Network Requirements This chapter provides test parameters and specification requirements for Full-Duplex Ethernet network cabling. Full-Duplex 10BASE-T All Cabletron Systems Full-Duplex 10BASE-T products require that installed facility cabling and cable hardware meet the following minimum specifications. If a network cabling installation is not within the limitations presented here, the operation of the 10BASE-T products may be affected.
Full-Duplex Ethernet Network Requirements Insertion Loss (Attenuation) The maximum allowable insertion loss for any 10BASE-T station on the Ethernet network is 11.5 dB at frequencies from 5 to 10 MHz. This calculation must take all cabling devices in the cable path into account. A typical insertion loss test must include the jumper cabling used at the station and at the wiring closet, and any patch panels, punchdown blocks, and wallplates in the installation.
Full-Duplex Ethernet Network Requirements Crosstalk Crosstalk is electrical interference between wires. Crosstalk occurs when a cable strand absorbs signals from adjacent wires. Excessive crosstalk can be caused by a break in the insulation or shielding that separates wires from one another in a bundle. Ethernet UTP cables should be checked for Near-End Crosstalk, or NEXT, at installation. The allowable amount of NEXT for a UTP cable is dependent upon the type of cable used in the installation.
Full-Duplex Ethernet Network Requirements The IEEE 802.3 10BASE-T specification requires that all 10BASE-T devices support UTP cables of not less than 100 m (328 ft) in length. This requirement does not factor in losses due to connectors, patch panels, punchdown blocks, or other cable management hardware, which introduce additional loss. For each connector or other intrusive cable management device in the total link, subtract 12 m (39.4 ft) from the total allowable link length.
Full-Duplex Ethernet Network Requirements Attenuation Multimode fiber optic cables must be tested for attenuation with a fiber optic attenuation test set. The test set must be configured to determine attenuation of the cable at a wavelength of 850 nm. The attenuation test will confirm or deny that the cable falls within an acceptable level. The acceptable level of attenuation for a cable is dependent upon the type of multimode fiber optic cable being tested.
Full-Duplex Ethernet Network Requirements Length The 10BASE-F specification limits a multimode fiber optic cable segment to 2 km or less. Assuming that a fiber optic cable meets all other limitations for 10BASE-F usage, it is possible to extend a multimode fiber optic link to an absolute maximum of 2 km. At a length of more than 2 km, the propagation delay introduced by the multimode fiber optic cable segment may exceed the 25.6 µs limit of the Ethernet specification and cause excessive OOW errors.
Full-Duplex Ethernet Network Requirements Insertion Loss The FOIRL specification allows for a total loss of 10.0 dB or less between any two stations or devices connected by fiber optic cabling. When calculating insertion loss, you must consider and count any loss introduced by fiber optic splices, barrel connectors, distribution boxes or other cable management devices. The typical dB loss for a splice or a connector is less than 1 dB.
Full-Duplex Ethernet Network Requirements 6-8 Ethernet FOIRL (Single Mode)
Chapter 7 Fast Ethernet Network Requirements This chapter provides test parameters and specification requirements for Fast Ethernet network cabling. 100BASE-TX All Cabletron Systems 100BASE-TX products require that installed facility cabling and cable hardware meet the following minimum specifications. If a network cabling installation is not within the limitations presented here, the operation of the 100BASE-TX products may be affected.
Fast Ethernet Network Requirements The TIA/EIA 568A cabling specification for Category 5 compliant UTP installations allows the use of two different types of cable: horizontal wire and patch wire. The specification allows horizontal wire to be used to cover distances of up to 90 m, while patch wire is restricted to a maximum length of 10 m. NOTE A third type of TIA/EIA 568 A cabling, backbone wire, does not apply to this implementation of the 100BASE-TX standard, and is not discussed in this chapter.
Fast Ethernet Network Requirements Delay The maximum propagation delay allowable on a 100BASE-TX segment is 1 microsecond (µs). If a Fast Ethernet signal is unable to traverse the entire length of an installed UTP cable run within 1 µs, Out of Window (OOW) errors will occur due to excessive delays between transmission of signals and notification of collisions. This propagation delay requirement limits UTP cabling to a total maximum length of 100 m (328 ft).
Fast Ethernet Network Requirements 100BASE-FX (Multimode) All Cabletron Systems 100BASE-FX products require that installed facility cabling and cable hardware meet the following minimum specifications. If a network cabling installation is not within the limitations presented here, the operation of the 100BASE-FX products may be affected. Cable Type Networking devices built to the 100BASE-FX specification require specific types of cabling.
Fast Ethernet Network Requirements Delay As fiber optic cabling is often used to make connections between Fast Ethernet repeaters or hubs, the 100BASE-FX specification allows a multimode fiber optic link to be configured such that the total propagation delay for the link is less than or equal to 2.56 µs one-way. Keep in mind, however, that propagation delay must be calculated for the entire network.
Fast Ethernet Network Requirements Link B Link A Fast Ethernet Repeater 1845n29a Figure 7-1. Fast Ethernet Network Radius If the two longest links in the Fast Ethernet repeater domain are both made using UTP cable, each UTP segment may be 100 m in length, for a total network radius of 200 m. If these links were both made using multimode fiber optics, the allowable maximum network radius would be 272 m, less than that allowed by a repeater with a single 100BASE-FX link.
Fast Ethernet Network Requirements The design and operation of these different repeater types result in different operating characteristics and network limitations. Class I repeaters, by translating the received signal, produce a stronger repeated transmission. The translation process, however, takes up a number of microseconds. This additional delay reduces the total distance a signal may travel before the allowable delay for that transmission has elapsed.
Fast Ethernet Network Requirements 7-8 Hybrid Installations
Chapter 8 Full-Duplex Fast Ethernet Network Requirements This chapter provides test parameters and specification requirements for Full-Duplex Fast Ethernet network cabling. 100BASE-TX All Cabletron Systems 100BASE-TX products require that installed facility cabling and cable hardware meet the following minimum specifications. If a network cabling installation is not within the limitations presented here, the operation of the 100BASE-TX products may be affected.
Full-Duplex Fast Ethernet Network Requirements Insertion Loss (Attenuation) The maximum allowable insertion loss for any 100BASE-TX station on the Fast Ethernet network is 11.5 dB at frequencies from 5 to 10 MHz. This calculation must take all cabling devices in the cable path into account. A typical insertion loss test must include the jumper cabling used at the station and at the wiring closet, and any patch panels, punchdown blocks, and wallplates in the installation.
Full-Duplex Fast Ethernet Network Requirements 25-Pair Cable The acceptable amount of NEXT between pairs in a 25-pair cable is at least 60 dB for a 10 MHz link. NOTE Due to the construction of the connectors and organization of wires, the 25-pair RJ21 connector is not Category 5 compliant. Four-Pair Cable The acceptable amount of NEXT between pairs in a four-pair cable is not less than 60 dB for a 10 MHz link.
Full-Duplex Fast Ethernet Network Requirements Length The 100BASE-TX standard specifies that any 100BASE-TX compliant device must be capable of transmitting a Fast Ethernet signal not less than 100 m (328 ft) over a UTP cable segment that meets the quality values listed above. As long as all specifications are met for the entire length of the cable, UTP cable segments can be run up to a maximum allowable length of 260 m (852 ft).
Full-Duplex Fast Ethernet Network Requirements 100BASE-FX (Multimode) All Cabletron Systems 100BASE-FX products require that installed facility cabling and cable hardware meet the following minimum specifications. If a network cabling installation is not within the limitations presented here, the operation of the 100BASE-FX products may be affected. Cable Type Cabletron Systems 100BASE-FX network devices require specific types of cabling.
Full-Duplex Fast Ethernet Network Requirements If there is any signal path whose total one-way propagation delay exceeds 2.56 µs, the Fast Ethernet network is out of specifications, and error conditions may result. To eliminate propagation delay problems, incorporate some form of segmentation, such as bridging or routing, into the network to separate the problem signal paths from one another. Length The 100BASE-FX specification limits a multimode fiber optic cable segment to 412 m or less.
Chapter 9 Token Ring Media This chapter examines the physical characteristics and requirements of both cabling and the connectors and ports used in Token Ring networks. Cabling Types Shielded Twisted Pair (STP) Shielded Twisted Pair cabling is a multistranded cable most often constructed of eight 26 AWG conductive copper solid or stranded core wires. Each wire is surrounded by a non-conductive insulating material such as Polyvinyl Chloride (PVC).
Token Ring Media Overall Shield Tx+ TxRxRx+ Outer Jacket Pair Shield 1845n21 Figure 9-1. STP Cable Pair Association Twisting the pairs together throughout the cable helps to reduce the effects of externally-induced electrical noise on the signals that pass through the cable. In each pair, one wire carries the normal network signal, while its associated wire carries a copy of the transmission that has been inverted.
Token Ring Media Induced Noise Spike Normal Transmission Noise spikes cancel out Original Signal Inverted Transmission Reversion of Inverted Transmission Resulting Signal 1845n05 Figure 9-2. Twisted Pair Signal Equalization STP cable is made up of four or more wires, and each wire within the cable has a specific insulator color. These colors are part of the IEEE specifications to which the cable construction process must be held. Each color identifies a particular usage for the cable.
Token Ring Media The individual wires are twisted into pairs. The pairs that are formed by this twisting are then surrounded by a mylar foil shield. These shielded pairs are then laid alongside one another in an overall braided metal shield. The shield containing the twisted pairs is then surrounded by a tight outer covering. Type 1 STP is heavy and rather inflexible, but provides excellent resistance to interference and noise due to its construction characteristics.
Token Ring Media Type 9 Type 9 cable is similar in construction to Type 6 cable, and is intended to be used for the same purposes. The center strands of a Type 9 cable are made of either solid or stranded 26 AWG conductors. Unshielded Twisted Pair (UTP) Unshielded Twisted Pair cabling (referred to here as UTP) is commonly made up of two or four pairs of 22, 24, or 26 AWG unshielded copper solid or stranded wires. These pairs of wires are twisted together throughout the length of the cable.
Token Ring Media While UTP cables are usually built to provide four pairs of wire, IEEE 802.5 standards only require the use of two pairs, referred to as Pair 1 and Pair 2 (Pair 1 and Pair 3 of the EIA/TIA 568A specification). Pair 2 of the connector is the transmit pair and Pair 1 of the connector is the receive pair. This organization of wires at the connector is referred to as a pinout. Pinouts will be discussed in greater detail in the Connector Types section of this chapter. Table 9-2. IEEE 802.
Token Ring Media Category 3 UTP cabling that is built to the Category 3 specification consists of two or more pairs of solid 24 AWG copper strands. Each strand, approximately 0.02 inch thick, is surrounded by a layer of insulation. The characteristics of the insulation are determined by the fire resistant construction of the cable (plenum cable is thicker and made with slightly different material than normal PVC cabling). The individual wires are twisted into pairs.
Token Ring Media Fiber Optics Fiber optic cable is a high performance media constructed of glass or plastic that uses pulses of light as a transmission method. Because fiber optics do not utilize electrical charges to pass data, they are free from the possibility of interference due to proximity to electrical fields. This, combined with the extremely low rate of signal degradation and dB loss makes fiber optics able to traverse extremely long distances.
Token Ring Media In much the same way that UTP cabling is available in two-, four-, 25-, and 50-pair cables, strands of fiber optic cabling are often bound together with other strands into multiple strand cables. These multiple strand cables are available with anywhere from two to 24 or more strands of fiber optics, all gathered together into one protective jacket.
Token Ring Media Connector Types STP Medium Interface Connector (MIC) The Medium Interface Connector is a genderless connector that is designed to be used with IBM Type 6 and Type 9 STP cabling. The MIC connector may also be used on Type 1 or Type 3 STP cabling. The design of the MIC connector allows it to be properly and securely connected to any other Token Ring MIC connector. It is made up of a plastic outer shell and four gold-plated contacts arranged in two rows of two each, as shown in Figure 9-4.
Token Ring Media DB9 The DB9 connector is a smaller standard connector for IEEE 802.5 networking applications, typically used for desktop and networking hardware connections. It is used in locations where a sturdy connection to STP cabling is required, but the use of MIC connectors is either impossible or undesirable. The DB9 cabling is usable on all types of STP cabling, but is most commonly found on jumper cabling such as IBM Types 6 and 9.
Token Ring Media The DB9 connector does not perform a wrap on disconnect as does the larger MIC connector. There is no internal mechanism for performing these operations. Stations connected to networking hardware with DB9 connectors rely on the networking hub to perform any wrapping in the event of a disconnection or cable error. STP wires that are connected to a DB9 cable must be set up in the fashion detailed below: Table 9-3. IEEE 802.5 DB9 Pinouts STP Wire Color IEEE 802.
Token Ring Media Plastic Hood Contact Blades Metal Shielding Locking Clip 1845n25 Figure 9-6. The Shielded RJ45 Connector The shielded RJ45 cable is made up of the plastic and metal outer housing and locking clip. Within the housing, a series of contact blades are lined up next to one another to provide contact points for the pins of the RJ45 port. The contact blades themselves are square-shaped, flat on three sides and with a set of two or three triangular teeth on one side.
Token Ring Media The wires of the STP cable must be organized in the RJ45 connector properly, based upon the USOC specification and the IEEE 802.5 specification. This organization of the wires at the connector is known as a pinout. The proper pinout for the Token Ring shielded RJ45 connector is given in Table 9-4, below. In addition to arranging the cables properly, the braided shield of the STP cable must be connected to the metal shield of the RJ45 connector.
Token Ring Media Unshielded Twisted Pair Cable RJ45 The RJ45 connector is a modular, plastic connector that is often used in UTP cable installations. The RJ45 is a keyed connector, designed to be plugged into an RJ45 port only in the correct alignment. The connector is a plastic housing that is crimped onto a length of UTP cable using a custom RJ45 die tool. The connector housing is often transparent, and consists of a main body, the pins, the raised key, and a locking clip.
Token Ring Media The wires of the UTP cable must be organized in the RJ45 connector properly, based upon the USOC specification and the IEEE 802.5 specification. This organization of the wires at the connector is known as a pinout. The proper pinout for the Token Ring RJ45 connector is given in Table 9-5. The USOC specification orders the pairs in a four-pair cable into the pinout shown in Figure 9-9, below.
Token Ring Media The connection of individual wires of a UTP cable to the pins of an IEEE 802.5 compliant RJ45 connector are given in Table 9-5. Table 9-5. IEEE 802.5 RJ45 Pinout for UTP Wire Color IEEE 802.5 Signal RJ45 Pinout White/Orange TX - 3 Blue RX + 4 White/Blue RX - 5 Orange TX + 6 Fiber Optics Straight-Tip Fiber optic connectors in Token Ring environments must meet the IEEE 802.
Token Ring Media The male ST connector is inserted into the channel of the female connector, its guide channels aligned with the locking pins of the female connector. Once the ST connector has been properly aligned, it is pressed in and rotated clockwise, the locking pins and guide channels pulling the ST connectors together. Once the locking pins have reached the ends of the guide channels, the ST connector locks into position.
Chapter 10 Token Ring Network Requirements This chapter provides test parameters and specification requirements for Token Ring network cabling. IEEE 802.5 Shielded Twisted Pair All Cabletron Systems Token Ring products for STP Token Ring connectivity require that installed facility cabling and cable management hardware meet the following minimum specifications.
Token Ring Network Requirements Attenuation The attenuation limit for any Token Ring STP cable link is dependent upon the operating speed of the Token Ring network. Token Ring networks that operate at a 16 Mbps speed (16 MHz) have slightly different cabling requirements than those Token Ring networks operating at 4 Mbps (4 MHz). Attenuation, when calculated, must take all cabling devices in the cable path into account.
Token Ring Network Requirements Link Length The operation of the Token Ring network places limitations on the amount of time a signal may travel through the Token Ring. This limitation, in conjunction with the amounts of loss that signals are susceptible to over different types of cabling, results in specified maximum link lengths for all cabling in any Token Ring network.
Token Ring Network Requirements Special Cases of Link Length If cable types are mixed in an installation, the different cable attenuations and qualities must be compensated for. In any installation, Type 6 and Type 9 cable may only be run for 2/3 the distance of Type 1 or Type 2 cable. This means that in order to be equivalent to a 10 meter length of Type 1 cable, Type 6 cable must be 2/3 of 10 meters, or 6.6 meters.
Token Ring Network Requirements IEEE 802.5 Unshielded Twisted Pair Cable Type The IEEE 802.5 specification for Token Ring networks requires UTP cabling of Category 3, 4, or 5. Categories of UTP cabling below Category 3 may not meet the quality requirements of the networking specification, and may therefore be unable to meet the tested characteristics listed below.
Token Ring Network Requirements Impedance All UTP cabling used in a Token Ring installation must test to an impedance of 85 to 115 Ohms. Cabling with higher or lower impedance ratings may not operate properly in the Token Ring network environment. Crosstalk Crosstalk is electrical interference between wires. Crosstalk occurs when a cable strand absorbs signals from other wires that it is adjacent to.
Token Ring Network Requirements When passive Token Ring technology is used, the link length for each network operating speed is reduced. A passive 4 Mbps Token Ring network may support Category 3 or 4 UTP cabling lengths of 100 m (328 ft) or less, while a 16 Mbps network can support a maximum length of 60 m (196 ft). Category 5 Category 5 UTP cabling, being of higher construction quality, is capable of supporting longer link lengths than UTP cabling of Categories 3 or 4.
Token Ring Network Requirements Category 5 The tested requirements for Category 5 UTP trunk cables are the same as those required for UTP lobe cables using Category 5 cabling. The maximum link length of a Category 5 trunk cable at 4 Mbps is 250 m (820 ft). A 16 Mbps Token Ring network would allow a maximum Category 5 UTP trunk link length of 120 m (393 ft). IEEE 802.5j (Multimode Fiber Optics) Cable Type IEEE 802.5j multimode fiber optic products for Token Ring networks require specific types of cabling.
Token Ring Network Requirements Attenuation Multimode fiber optic cables must be tested for attenuation with a fiber optic attenuation test set. The test set must be configured to determine attenuation of the cable at a wavelength of 850 nm. The attenuation test will confirm or deny that the cable falls within an acceptable level. The acceptable level of attenuation for a cable is dependent upon the type of multimode fiber optic cable being tested.
Token Ring Network Requirements IEEE 802.5j Single Mode Fiber Optics Cable Type IEEE 802.5j single mode fiber optic products for Token Ring networks require specific types of cabling. Token Ring single mode fiber optic devices manufactured by Cabletron Systems are able to support connections to and from the following construction sizes of single mode fiber optics: • • 8.
Chapter 11 FDDI Media This chapter details the standard media and connector types that may be used in Fiber Distributed Data Interface (FDDI) networks. Cabling Types Unshielded Twisted Pair (UTP) Unshielded Twisted Pair cabling (referred to here as UTP, but also may be termed copper wire, 10BASE-T wire, Category 5 wire, telephone cable, or twisted pair without shielded or unshielded qualifier) is commonly made up of four pairs of 22, 24, or 26 AWG unshielded copper solid or stranded wires.
FDDI Media In any transceiver or Network Interface Card (NIC), the network protocol signals to be transmitted are in the form of changes of electrical state. The means by which the ones and zeroes of network communications are turned into these signals is called encoding. In a twisted pair environment, once a transceiver has been given an encoded signal to transmit, it will copy the signal and invert the polarity of that signal (see Figure 11-2, below).
FDDI Media The UTP cable used in network installations is the same type of cable used in the installation of telephone lines within buildings. UTP cabling is differentiated by the quality category of the cable itself, which is an indicator of the type and quality of wire used and the number of times the wires are twisted around each other per foot. The categories range from Category 1 to Category 5, with Category 5 cabling being of the highest quality.
FDDI Media To overcome this, a crossover must be placed between the FDDI TP-PMD ports, forcing the transmit pins of one device to connect to the receive pins of the other device. When two devices are being connected to one another using UTP cabling, an odd number of crossover cables, preferably one, must be part of the cabling between them.
FDDI Media Category 5 UTP consists of 2 or more pairs of 22 or 24 AWG wire. Category 5 cable is constructed and insulated such that the maximum attenuation of a 10 MHz signal in a cable run at the control temperature of 20° C is 65 dB/km. A cable that has a higher maximum attenuation than 65 dB/km does not meet the Category 5 requirements. Shielded Twisted Pair (STP) The TP-PMD specification is also able to utilize high-quality Shielded Twisted Pair, or STP cable.
FDDI Media In any transceiver or Network Interface Card (NIC), the network protocol signals to be transmitted are in the form of changes of electrical state. The means by which the ones and zeroes of network communications are turned into these signals is called encoding. In a twisted pair environment, once a transceiver has been given an encoded signal to transmit, it copies the signal and inverts the voltage (see Figure 11-5, below).
FDDI Media Table 11-1. STP Cable Wire Identifications NOTE Cable Color Application Black TX - Red RX + Green RX - Orange TX + As STP cabling provides only two pairs of wire, it may only be used for Single Attached Station connections from FDDI concentrators to stations (M ports to S ports). STP Cable Quality STP cable is available in a series of construction and quality styles, known as Types.
FDDI Media Type 2 IBM Type 2 cable is constructed in much the same fashion as Type 1 cable. The two central shielded pairs and the overall braided shield that surround them are constructed of the same materials, and then two additional pairs of AWG 22 insulated solid copper wires are laid outside the braided shield before the whole cable is surrounded by the tight outer covering.
FDDI Media There are two basic types of fiber optics: multimode and single mode. The names come from the types of light used in the transmission process. Multimode fiber uses inexpensive Light Emitting Diodes (LEDs) that produce light of a single color. Due to the nature of the LED, the light produced is made up of a number of differing wavelengths of light, fired outward from the center of the LED.
FDDI Media Multimode Multimode fiber optic cabling is designed and formulated to allow the propagation of many different wavelengths, or modes, of light. Multimode fiber optics are the most commonly encountered fiber type in FDDI installations, due to their lower cost compared to other fiber types. The FDDI MMF-PMD specification specifies the Media Interface Connector, or MIC, as the standard connector for MMF-PMD networks.
FDDI Media Connector Types UTP RJ45 The RJ45 connector is a modular, plastic connector that is often used in UTP cable installations. The RJ45 is a keyed connector, designed to be plugged into an RJ45 port only in the correct alignment. The connector is a plastic housing that is crimped onto a length of UTP cable using a custom RJ45 die tool. The connector housing is often transparent, and consists of a main body, the pins, the raised key, and a locking clip.
FDDI Media Pair 2 Pair 3 W-GR GR Pair 4 Pair 1 W-OR BL W-BL OR W-BR BR 1845n16 Figure 11-7. EIA/TIA 568A Pinout and Pair Association The EIA/TIA 568 B specification reverses the arrangement of Pair 1 and Pair 2, but does not change the association of pairs within the cable. The Universal Service Order Code, or USOC, a standard often used for older building telephone wiring, uses a different pair association than EIA/TIA 568A.
FDDI Media NOTE The type of STP cable required by FDDI TP-PMD networking equipment is constructed with solid core wires only. Do not use RJ45 connectors with contact blades designed for stranded cable. An STP cable that uses solid core wires requires the use of contact blades with three teeth. This is due to the inability of the teeth to effectively penetrate the solid core of the STP wire without damaging the cable.
FDDI Media Guide Channel Locking Arm 1845n27 "Floating" Ferrules Figure 11-8. FDDI Media Interface Connector The MIC connector is designed to prevent the mis-connection of segments and devices. It is specifically constructed in an asymmetrical fashion that prevents the connection of transmit strands in the connector to the transmit devices of an FDDI device.
FDDI Media SC Connector The SC connector is a gendered connector that is recommended for use in FDDI networks that incorporate multimode fiber optics adhering to the LCF-PMD specification. It consists of two plastic housings, the outer and inner. The inner housing fits loosely into the outer, and slides back and forth with a travel of approximately 2 mm (0.08 in). The inner housing ends in two floating ferrules, which are very similar to the floating ferrules used in the FDDI MIC connector.
FDDI Media 11-16 Connector Types
Chapter 12 FDDI Network Requirements This chapter details the test specifications and limitations for media used in FDDI networks. MMF-PMD Cable Type The FDDI PMD specification that deals with multimode fiber optic cabling in FDDI environments specifies the use of 62.5/125 µm fiber optic cabling which is designed for use with 1300 nm wavelengths. Other sizes of fiber optic cabling may be used with MMF-PMD compliant products, but the performance of links made with these nonstandard cables will be reduced.
FDDI Network Requirements Length As long as all other cable quality specifications are met, the FDDI PMD allows a multimode fiber optic link to be no longer than 2 km from station to station. This 2 km length must include all connector and patch panels between the two stations. Keep in mind when determining the maximum length of an FDDI fiber optic link that the FDDI network may not exceed a maximum total length of 100 km.
FDDI Network Requirements Length If all other cable quality specifications are met, the FDDI SMF-PMD allows a single mode fiber optic link to be no longer than 58 km from station to station. This total length must include all connector and patch panels between the two stations. Keep in mind when determining the maximum length of an FDDI fiber optic link that the FDDI network may not exceed a total length of 100 km.
FDDI Network Requirements Length Assuming that all other cable quality specifications are met, the FDDI LCF-PMD allows a low-cost fiber optic link to be no longer than 500 m from station to station. This total length must include all connectors and patch panels between the two stations. Keep in mind when determining the maximum length of an FDDI fiber optic link that the FDDI network may not exceed a total length of 100 km.
FDDI Network Requirements Length TP-PMD cabling which is within all other requirements of the specification may be no longer than 100 m from station to station. This total length must include all connectors and patch panels between the two stations. As with fiber optic connections, it is important to remember the 100 km total ring length of FDDI networks when planning installations. TP-PMD (STP) Cable Type The TP-PMD specification demands cables of very high quality.
FDDI Network Requirements 12-6 TP-PMD (STP)
Chapter 13 Cabling Devices This chapter identifies a number of commonly-used cabling installation and management devices which may be used to facilitate easy network troubleshooting, installation, and expansion. Cable management devices are those pieces of equipment which allow the organization of cables and networking hardware into well-defined and easily modified groups.
Cabling Devices Hardware Mounting Relay Rack The relay rack, or electrical equipment rack, is a metal frame that is commonly used to secure and support networking, electrical, or telephony equipment in network centers or wiring closets. Most large cable management devices and networking products such as modular chassis are designed to be either mounted directly in the relay rack or placed on shelves set up in the rack. Relay racks are available in a range of heights from as small as one meter (3.
Cabling Devices Enclosed Equipment Cabinet The enclosed equipment cabinet, sometime referred to as a “glass front rack,” is basically a relay rack inside a protective metal frame. The enclosed equipment cabinet allows networking devices to be secured as though in a relay rack, and also prevents unauthorized access to the equipment. Keeping the cabinet door closed and locked helps to ensure that unauthorized personnel will not be able to modify the current organization of cables and devices.
Cabling Devices Cable Termination Cable termination equipment provides points where facility cabling may be easily connected to jumper cabling. Cable termination equipment basically provides endpoints for the raw facility cabling. Patch Panel A patch panel is a piece of cable termination equipment which connects raw facility cabling to standard ports or connectors.
Cabling Devices Harmonica The Harmonica is a specialized type of patch panel. It is used only in twisted pair networking situations. The harmonica provides front surface modular connections like a patch panel. The back surface provides one or more RJ21 connectors. Through the use of a harmonica, one or more 24-pair UTP cables with 50-pin connectors can be broken out into 12 separate RJ45 ports. RJ45 Ports Labeling Windows Front Rear 50-pin RJ21 Port 1845n32 Figure 13-4.
Cabling Devices Punchdown Block A punchdown block is another means of attaching raw strands of facility cable to a single jumper cable. The punchdown block allows the actual metal strands of facility UTP cable to be punched down, using a special tool, onto bayonet pins. These bayonet pins are connected to one another through the punchdown block’s internal wiring. Most punchdown blocks wire the leftmost column of pins to the left inside column, and the rightmost column of pins to the inside right column.
Cabling Devices Distribution Box A distribution box is a form of patch panel that is used with fiber optic cabling. The distribution box provides an access point for multiple strand facility fiber optic cable. As distribution boxes are commonly used as intermediary cabling devices, they are designed to be mounted to walls or ceilings. Hinged or Latched Access Door Fiber Optic Barrel Connectors Two-strand Jumper Cable 12-strand Facility Cable 1845n34 Figure 13-6.
Cabling Devices Wallplate A wallplate is a form of small patch panel typically used at end user locations. The wallplate provides a connection and termination point for the facility cabling to which a user station may be connected with a length of jumper cabling. Wallplates are available in several styles, and for all types of standard connectors. Wallplates may provide only one connector, or may be capable of supporting eight or more separate connectors.
Cabling Devices Surface Mount Box A surface mount box is a type of wallplate which, instead of being mounted in a hole in the wall is attached to the wall with an adhesive. The surface mount box is typically used in locations where connections to end user stations are to be made from a wall which is constructed of a material that is not easily cut through. Firewalls, cinderblock, and packed-earth are some of the wall types that should not be punctured to run cabling.
Cabling Devices D-Rings D-rings are metal rings that are mounted to a wall or beam. The D-rings are shaped like the letter “D”. Once the rings are in place and secured (using screws, rivets, or adhesive) cabling is passed through the rings. The D-rings support the weight of the cables run through them and keep the cables in one location. D-rings may also be useful for holding cables away from sources of electrical interference or physical damage, such as lighting, automation, or HVAC equipment.
Cabling Devices J-Hooks J-hooks are cable management devices similar in form and function to D-rings. Whereas a D-ring, once mounted on a wall, support, or other solid surface, is a closed hoop through which cable is threaded, J-hooks are open, and simply act as a support for the cable. J-hooks are often used to provide strain relief at strategic points in a run of cable or bundle of cables, or may be used in locations where cables must be added or removed from easily-accessible areas often.
Cabling Devices Innerduct Innerduct is a corrugated plastic tubing that is used to protect cabling. Most often, innerduct is used with fiber optic cabling, due to that media’s susceptibility to damage during or following installation. Typically bright orange in color, innerduct may be pulled through a conduit or raceway before fiber optic cable installation, or used in areas where the cable would otherwise be exposed. Innerduct 1845n39 Fiber Optic cable Figure 13-11.
Cabling Devices Raceway The term “Raceway” is used to refer to several items in cable installation. A raceway of any type is a channel, tray, or platform along which cable is laid. Most raceways are differentiated from conduits in the construction of each; where a conduit is a cylinder that is closed on all sides and open at both ends, raceway is typically open on one side along its entire length. Floor raceway is a channel or trench set into the floor of a facility that cable may be placed in.
Cabling Devices Ty-Wraps and Adhesive Anchors Ty-Wraps, also called Ty-Fasts, plastic securing straps, and zip straps, are ribbons of tough plastic, usually white in color. The center portion of the plastic strip is ribbed or knurled, and one end of the strap is a slot with a racheting or friction-based means of holding the center portion of the plastic ribbon tightly. Ty-wraps are typically wrapped around a cable or bundle of cables.
Chapter 14 Connecting and Terminating This chapter deals with the methods used to attach connectors to facility or jumper cables and the termination requirements of the cable and connector types. Ethernet DB15 DB15 connectors and ports are used to make connections between Ethernet transceivers and Ethernet stations. The DB15 connector is the most commonly encountered Ethernet AUI cable connector, and is often used to connect a workstation or Ethernet device to a coaxial cable backbone.
Connecting and Terminating 1. Align the DB15 connector of the AUI cable with the AUI port of the network device as shown in Figure 14-1. The port will only connect if it is properly aligned. 1845n43 Figure 14-1. DB15 Connector Insertion 2. Firmly press the AUI connector over the AUI port. The locking clips on the sides of the AUI connector should snap into place when the connection is made. 3. If a sliding latch is present on the connector or port, slide it into place to secure the connector to the port.
Connecting and Terminating To remove the DB15 connector from the port once it is locked in, examine the connector for a sliding latch or other locking method. If one is present, slide it to the unlocked position. Grasp the connector firmly between your thumb and forefinger. Pull the connector straight out of the port. The spring clips at the side of the connector should disengage under light strain and allow the connector to pull free.
Connecting and Terminating • Check that the twisted pair connection meets dB loss and cable specifications outlined in 10BASE-T Twisted Pair Network Requirements. • If all else fails, contact Cabletron Systems Technical Support. To remove the RJ45 connector from the port once it is locked in, grasp the cable where it enters the network device. Using your finger or a non-conductive probe, pinch the exposed arm of the locking clip towards the main body of the housing.
Connecting and Terminating 2. When the RJ21 connector has been correctly inserted, it should remain in place naturally. If there are Velcro fastening straps provided, use them to secure the connector to the port. If link indicators are present for the ports serviced by the RJ21 connector, check that they are on. If an indicator is not on, that port does not have a valid link. Perform each of the following actions until you reach a resolution of the problem and achieve a link.
Connecting and Terminating 2. Once the housing stops moving in, turn the metal housing clockwise while continuing to apply light forward pressure. It is likely that the female connector will have to be secured in order to stop it from rotating as you turn the male connector. 3. The locking keys of the female connector will pull the connector in until they reach the circular locking holes at the end of the guide channels. The keys will click the connector into place and hold it there.
Connecting and Terminating N-Type The N-Type connector is used for intrusive taps in thick coaxial cabling. The instructions which follow detail the process used to connect a male N-Type connector to a female N-Type barrel connector. Before attaching a male N-Type connector to a female N-Type barrel connector or terminator, look into the end of the male connector to verify that the gold contact pins are present and centered. Any bent or broken pins may not connect properly and should be replaced.
Connecting and Terminating 1. Remove the protective plastic covers from the fiber optic ports on the applicable port on the module, and from the ends of the connectors on each fiber strand. ! CAUT ION Do not touch the ends of the fiber optic strands, and do not let the ends come in contact with dust, dirt, or other contaminants. Contamination of cable ends causes problems in data transmissions. If necessary, clean contaminated cable ends using alcohol and a soft, clean, lint-free cloth. 2.
Connecting and Terminating Token Ring DB9 The DB9 connector is often used to connect Token Ring stations to STP jumper cables. The instructions which follow detail the process used to connect a DB9 connector to a station port. NOTE The DB9 connector looks identical to the PC EGA monitor connector. If a Token Ring lobe connection is attached to the monitor port, the Token Ring network will enter an error state.
Connecting and Terminating If a link indicator is present for the port, check to see if it is on. If it is not on, perform the following actions until you reach a resolution of the problem and achieve a link. • Check that the Token Ring device at the other end of the AUI segment is operating. • Verify proper crossover of the STP segment. • Check the DB9 connector for bent or missing pins. Keep in mind that several DB9 connectors provide only four pins at the connector.
Connecting and Terminating 2. Press the RJ45 connector into the port until the click of the locking clip is felt. The pressure required to perform this should be minimal. If you encounter resistance or excessive friction, remove the connector and check the port for obstruction. Also, verify that the connector and the port are of the same type. Once the locking clip snaps into place, the RJ45 connector will remain in the port. If a link indicator is present for the port, check that it is on.
Connecting and Terminating Token Ring MIC Token Ring MIC connectors only attach to other Token Ring MIC connectors or ports. In order to connect two Token Ring MICs, perform the following procedures: 1. Align the connectors such that the moving arms at the outside edges of both connectors are aligned. Looking at the connectors from the side, it should be obvious if the connectors will nest properly in their current arrangement. 1845n50 Figure 14-9. Token Ring MIC Connector Insertion 2.
Connecting and Terminating ST Connector The instructions which follow detail the process used to connect a set of ST connectors to a station port. ST connectors for fiber optic cables are connected to ST ports on devices through a “twist and lock” procedure. Each fiber optic link consists of two strands of fiber optic cabling: the transmit (TX) and the receive (RX). The transmit strand from a module port connects to the receive port of a fiber optic Ethernet device at the other end of the segment.
Connecting and Terminating If link indicators are present for the fiber optic connection, check that they are on. If an indicator is present but not on, that port does not have a valid link. Perform each of the following actions until you reach a resolution of the problem and achieve a link. • Check that the device at the other end of the link is on. • Verify proper cross-over of the fiber strands. Try swapping the transmit and receive connections at only one end of the link.
Connecting and Terminating If a link indicator is present for the port, check that it is on. If the indicator is not on, the port does not have a valid link. Perform each of the following actions until you reach a resolution of the problem and achieve a link. • Check that the FDDI device at the other end of the twisted pair segment is on. • Verify that the RJ45 connectors on the twisted pair segment have the proper pinouts. • Check the cable for continuity.
Connecting and Terminating FDDI MIC Before attaching connectors to an FDDI MIC port, remove the protective rubber plug from the FDDI port. Also remove the plastic hood from the MIC connector to be used. Usually, there will be three plastic inserts, colored red, blue, and green, in holders on the connector hood. These plastic inserts are used to key the MIC connector for use only in certain types of FDDI ports. Using a paper clip or probe, push the insert you require out of its holder.
Connecting and Terminating 1845n51 Figure 14-12. FDDI Media Interface Connector Insertion The link LED associated with the port should come on, indicating a valid link. If the link LED for the port does not light up, there is a condition present which will not allow the FDDI device to recognize a link. Perform the following examinations and actions until you achieve a link. • Check that the FDDI device at the other end of the cable is on.
Connecting and Terminating SC Connector Each fiber optic link consists of two strands of fiber optic cabling: the transmit (TX) and the receive (RX). The transmit strand from a module port connects to the receive port of a fiber optic Ethernet device at the other end of the segment. The receive strand of the applicable port on the module connects to the transmit port of the fiber optic Ethernet device.
Connecting and Terminating If link indicators are present for the fiber optic connection, check that they are on. If an indicator is present but not on, that port does not have a valid link. Perform each of the following actions until you reach a resolution of the problem and achieve a link. • Check that the device at the other end of the link is on. • Verify proper crossover of the fiber strands. Try swapping the transmit and receive connections at only one end of the link.
Connecting and Terminating 14-20 FDDI
Appendix A Charts and Tables This chapter presents essential information dealing with the minimum, maximum, and recommended characteristics for standards-compliant cabling for Ethernet, Token Ring, and FDDI networks. Ethernet 10BASE5 Cable Characteristics Aspect Limit Tap Spacing ≥ 2.5 m Max Length 500 m Max Stations 100 10BASE2 Cable Characteristics Aspect Limit Tap Spacing ≥ 0.
Charts and Tables 10BASE-T Cable Characteristics Aspect Limit Impedance 75 - 165 Ω Insertion Loss @ 10 MHz 11.5 dB Jitter ≤ 5.0 ns One-way Propagation Delay 1000 ns Max Length 200 m 10BASE-F Cable Characteristics (multimode) 50/125 µm 62.5/125 µm 100/140 µm Attenuation @ 850 nm ≤ 13.0 dB ≤ 16.0 dB ≤ 19.0 dB Insertion Loss @ 10 MHz ≤ 10 dB ≤ 10 dB ≤ 10 dB Aspect 25.
Charts and Tables These are not correct yet: 100BASE-TX Cable Characteristics Aspect Limit Impedance 75 - 165 Ω Insertion Loss @ 10 MHz 11.5 dB Jitter ≤ 5.0 ns One-way Propagation Delay 1000 ns Max Length (simplex) 200 m Max Length (duplex) 200 m 100BASE-FX Cable Characteristics (multimode) 50/125 µm 62.5/125 µm 100/140 µm Attenuation @ 850 nm ≤ 13.0 dB ≤ 16.0 dB ≤ 19.0 dB Insertion Loss @ 10 MHz ≤ 10 dB ≤ 10 dB ≤ 10 dB Aspect 25.
Charts and Tables Token Ring Lobe Cable Distances Media Circuitry active STP passive active UTP passive Fiber Optics active Cable Type Max Lobe Length 4 Mbps 16 Mbps IBM Types 1, 2 300 m 150 m IBM Types 6, 9* 200 m 100 m IBM Types 1, 2 200 m 100 m IBM Type 9 133 m 66 m Category 5 250 m 120 m Categories 3, 4 200 m 100 m Category 5 130 m 85 m Categories 3, 4 100 m 60 m Multimode 2000 m 2000 m Single Mode 2000 m 2000 m *.
Charts and Tables STP Test Requirements Type 1/2 Type 6/9 Aspect 4 Mbps 16 Mbps 4 Mbps 16 Mbps 127.5 - 172.
Charts and Tables FDDI Maximum Cable Distances Table 14-2. FDDI Distance Limitations Media PMD Standard Max Link Distance Fiber Optics (Multimode) MMF-PMD 2 km Fiber Optics (Single Mode) SMF-PMD 60 km Unshielded Twisted Pair* Shielded Twisted Pair† TP-PMD 100 m 100 m *. Category 5 UTP cabling only †.
Glossa This glossary provides brief descriptions of some of the recurrent terms in the main text, as well as related terms used in discussions of the relevant networking discussions. These descriptions are not intended to be comprehensive discussions of the subject matter. For further clarification of these terms, you may wish to refer to the treatments of these terms in the main text.
Attenuation to Card Attenuation Loss of signal power (measured in decibels) due to transmission through a cable. Attenuation is dependent on the type, manufacture and installation quality of cabling, and is expressed in units of loss per length, most often dB/m. AUI Attachment Unit Interface. A cabling type used in Ethernet networks, designed to connect network stations and devices to transceivers.
Channel to Crosstalk Channel A portion of a backplane bus which is specifically partitioned off for the transmission of one type of network data. Chassis See Modular Chassis. Client A workstation or node which obtains services from a server device located on the network. Client-Server A computing model which is based on the use of dedicated devices (servers) for the performance of specific computational or networking tasks.
CSMA/CD to Dual Attached CSMA/CD Carrier Sense Multiple Access with Collision Detection. CSMA/CD is the basis for the operation of Ethernet networks. CSMA/CD is the method by which stations monitor the network, determine when to transmit data, and what to do if they sense a collision or other error during that transmission. Data Information, typically in the form of a series of bits, which is intended to be stored, altered, displayed, transmitted, or processed.
Dual Homing to FNB Dual Homing A station connection method for FDDI which connects a device’s A/B ports to the M ports of two separate dual-attached concentrator devices, providing fault-tolerance. EEPROM Electronic Erasable Programmable Read-Only Memory. Encryption A security process which encodes raw data into a form that cannot be utilized or read without decryption. EPIM Ethernet Port Interface Module.
Frame to Interface Frame A group of bits that form a discrete block of information. Frames contain network control information or data. The size and composition of a frame is determined by the network protocol being used. Frames are typically generated by operations at the Data Link Layer (Layer 2) of the OSI Model. Gateway A device which connects networks with dissimilar network architectures and which operates at the Application Layer of the OSI Model. May also be used to refer to a router.
Internet to MAU Internet A world-wide network which provides access through a vast chain of private and public LANs. Interoperability The capacity to function in conjunction with other devices. Used primarily to indicate the ability of different vendors’ networking products to work together cohesively. IP Internet Protocol. IP Address Internet Protocol address. The IP address is associated, by the network manager or network designer, to a specific interface.
Mbps to NVRAM Mbps Megabits Per Second. Mbps indicates the number of groups of 1000 bits of data that are being transmitted through an operating network. Mbps can be roughly assessed as a measure of the operational “speed” of the network. Media Physical cabling or other method of interconnection through which network signals are transmitted and received. MIC Connector 1: Token Ring genderless connector. 2: FDDI fiber optic connector which may be keyed to act as an M or S connector or A/B connector.
Octet to Redundant Octet A numerical value made up of eight binary places (bits). Octets can represent decimal numbers from zero (0000 0000) to 255 (1111 1111). OID Object Identifier. OSI Model Open Standards Interconnect. A model of the way in which network communications should proceed from the user process to the physical media and back. Out-Of-Band Performed without requiring the operation of the network technology. Most commonly used in reference to local management operations.
Relay to SIMM Relay An electrical switch which opens and closes in response to the application of voltage or current. Repeater A network device consisting of a receiver and transmitter which is used to regenerate a network signal to increase the distance it may traverse. Ring-In/Ring-Out Token Ring connections which are made between MAUs utilizing two separate physical cables and incorporating an auto-wrap recovery feature. RJ45 A modular connector style used with twisted pair cabling.
Single Attached to Subnet Mask Single Attached Connected to an FDDI network through a single cable which does not provide for auto-wrap functions. Single Mode A type of fiber optics in which light travels in one predefined mode, or wavelength. Signals in single mode fiber optics are typically driven by lasers. The use of lasers and the transmission characteristics of single mode fiber optics allow the media to cover greater distances than multimode fiber optics. SMA Sub-Miniature Assembly.
Switch to UTP Switch A network device which connects two or more separate network segments and allows traffic to be passed between them when necessary. A switch determines if a packet should be blocked or transmitted based on the destination address contained in that packet. TCP Transmission Control Protocol. Terminal A device for displaying information and relaying communications.
Index Numerics 100BASE-FX attenuation 7-4, 8-5 cable requirements 7-4, 8-5 full-duplex 8-5 insertion loss 7-4, 8-5 link length 8-6 multimode 7-5 propagation delay 7-5, 8-5 100BASE-TX attenuation 7-2, 7-3, 8-2, 8-3 cable requirements 7-1, 8-1 crosstalk 7-3, 8-2 full-duplex 8-1 impedance 7-2, 8-2 interference - See crosstalk, above interference See crosstalk, above jitter requirements 7-2, 8-2 link length 8-2, 8-4 propagation delay 7-3 10BASE2 cable requirements 5-8 connections 5-8 grounding requirements 5-9
D DB15 connector 4-17 pinout 4-17 Document organization 1-2 E EIA/TIA 568A RJ45 jack 4-24 definition 3-1 pair association 4-7 Ethernet - See applicable 10BASE standard F FDDI LCF-PMD attenuation 12-3 cable type 12-3 cable types 11-10 connectors 11-15 link length 12-4 power 12-4 MMF-PMD attenuation 12-1 cable types 11-10, 12-1 connectors 11-13 link length 12-2 power 12-2 SMF-PMD attenuation 12-2, 12-3 cable type 12-2 cable types 11-10 connectors 11-13 power 12-3 TP-PMD crossovers 11-4 STP attenuation 12-5
P Patch panel 13-4 Punchdown block 4-26, 13-6 R Related documents 1-4 RG58 A/U - See 10BASE2 RJ21 4-25 pair mapping 4-9 RJ45 4-23, 11-11 RJ45 (shielded) 11-12 S SC connector 4-29, 11-15 SMF-PMD - See FDDI ST connector 4-28 STP 9-1 T UTP attenuation 10-5 crosstalk 10-6 impedance 10-6 link length 10-6 trunk length 10-7 TP-PMD - See FDDI Twisted Pair shielded 9-1 unshielded 4-5 U USOC definition 3-2 UTP 25-pair cable 4-8 categories 4-6, 4-13 description 4-5 four-pair 4-7 wire color 4-7, 4-9 T-connector 4
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