Black Box Explains...The MPO connector.
MPO stands for multifiber push-on connector. It is a connector for multifiber ribbon cable that generally contains 6, 8, 12, or 24 fibers. It is defined by IEC-61754-7 and TIA-604-5-D,... more/see it nowalso known as FOCIS 5. The MPO connector, combined with lightweight ribbon cable, represents a huge technological advance over traditional multifiber cables. It’s lighter, more compact, easier to install, and less expensive.
A single MPO connector replaces up to 12, 24, or 36 standard connectors. This very high density means lower space requirements and reduced costs for your installation. Traditional, tight-buffered multifiber cable needs to have each fiber individually terminated by a skilled technician. But MPO fiber optic cable, which carries multiple fibers, comes preterminated.
Just plug it in and you’re ready to go.
MPO connectors feature an intuitive push-pull latching sleeve mechanism with an audible click upon connection and are easy to use. The MPO connector is similar to the MT-RJ connector. The MPO’s ferrule surface of 2.45 x 6.40 mm is slightly bigger than the MT-RJ’s, and the latching mechanism works with a sliding sleeve latch rather than a push-in latch.
The MPO connector can be either male or female. You can tell the male connector by the two alignment pins protruding from the end of the ferrule. The MPO ferrule is generally flat for multimode applications and angled for single-mode applications.
MPO connectors are also commonly called MTP® connectors, which is a registered trademark of US Conec. The MTP connector is an MPO connector engineered with particular enhancements to improve optical and mechanical performance. The two connectors are compatible.
Black Box Explains...10-Gigabit Ethernet.
10-Gigabit Ethernet, sometimes called 10-GbE or 10 GigE, is the latest improvement on the Ethernet standard, ratified in 2003 for fiber as the 802.3ae standard, in 2004 for twinax cable... more/see it now
as the 802.3ak standard, and in 2006 for UTP as the 802.3an standard.
10-Gigabit Ethernet offers ten times the speed of Gigabit Ethernet. This extraordinary throughput plus compatibility with existing Ethernet standards has resulted in 10-Gigabit Ethernet quickly becoming the new standard for high-speed network backbones, largely supplanting older technologies such as ATM over SONET. 10-Gigabit Ethernet has even made inroads in the area of storage area networks (SAN) where Fibre Channel has long been the dominant standard. This new Ethernet standard offers a fast, simple, relatively inexpensive way to incorporate super high-speed links into your network.
Because 10-Gigabit Ethernet is simply an extension of the existing Ethernet standards family, it’s a true Ethernet standard—it’s totally backwards compatible and retains full compatibility with 10-/100-/1000-Mbps Ethernet. It has no impact on existing Ethernet nodes, enabling you to seamlessly upgrade your network with straightforward upgrade paths and scalability.
10-Gigabit Ethernet is less costly to install than older high-speed standards such as ATM.
And not only is it relatively inexpensive to install, but the cost of network maintenance and management also stays low—10-Gigabit Ethernet can easily be managed by local network administrators.
10-Gigabit Ethernet is also more efficient than other high-speed standards. Because it uses the same Ethernet frames as earlier Ethernet standards, it can be integrated into your network using switches rather than routers. Packets don’t need to be fragmented, reassembled, or translated for data to get through.
Unlike earlier Ethernet standards, which operate in half- or full-duplex, 10-Gigabit Ethernet operates in full-duplex only, eliminating collisions and abandoning the CSMA/CD protocol used to negotiate half-duplex links. It maintains MAC frame compatibility with earlier Ethernet standards with 64- to 1518-byte frame lengths. The 10-Gigabit standard does not support jumbo frames, although there are proprietary methods for accommodating them.
Fiber 10-Gigabit Ethernet standards
There are two groups of physical-layer (PHY) 10-Gigabit Ethernet standards for fiber:
LAN-PHY and WAN-PHY.
LAN-PHY is the most common group of standards. It’s used for simple switch and router
connections over privately owned fiber and uses a line rate of 10.3125 Gbps with 64B/66B
The other group of 10-Gigabit Ethernet standards, WAN-PHY, is used with SONET/SDH
interfaces for wide area networking across cities, states—even internationally.
10GBASE-SR (Short-Range) is a serial short-range fiber standard that operates over two multimode fibers. It has a range of 26 to 82 meters (85 to 269 ft.) over legacy 62.5-µm 850-nm fiber and up to 300 meters (984 ft.) over 50-µm 850-nm fiber.
10GBASE-LR (Long-Range) is a serial long-range 10-Gbps Ethernet standard that operates at ranges of up to 25 kilometers (15.5 mi.) on two 1310-nm single-mode fibers.
10GBASE-ER (Extended-Range) is similar to 10GBASE-LR but supports distances up to 40 kilometers (24.9 mi.) over two 1550-nm single-mode fibers.
10GBASE-LX4 uses Coarse-Wavelength Division Multiplexing (CWDM) to achieve ranges of 300 meters (984 ft.) over two legacy 850-nm multimode fibers or up to 10 kilometers (6.2 mi.) over two 1310-nm single-mode fibers. This standard multiplexes four data streams over four different wavelengths in the range of 1300 nm. Each wavelength carries 3.125 Gbps to achieve 10-Gigabit speed.
In fiber-based Gigabit Ethernet, the 10GBASE-SR, 10GBASE-LR, and 10GBASE-ER LAN-PHY standards have WAN-PHY equivalents called 10GBASE-SW, 10GBASE-LW, and 10GBASE-EW. There is no WAN-PHY standard corresponding to 10GBASE-LX4.
WAN-PHY standards are designed to operate across high-speed systems such as SONET and SDH. These systems are often telco operated and can be used to provide high-speed data delivery worldwide. WAN-PHY 10-Gigabit Ethernet operates within SDH and SONET using an SDH/SONET frame running at 9.953 Gbps without the need to directly map Ethernet frames into SDH/SONET.
WAN-PHY is transparent to data—from the user’s perspective it looks exactly the same as LAN-PHY.
10-Gigabit Ethernet over Copper
10GBASE-CX4 is a standard that enables Ethernet to run over CX4 cable, which consists of four twinaxial copper pairs bundled into a single cable. CX4 cable is also used in high-speed InfiniBand® and Fibre Channel storage applications.
Although CX4 cable is somewhat less expensive to install than fiber optic cable, it’s limited to distances of up to 15 meters. Because this standard uses such a specialized cable at short distances, 10GBASE-CX4 is generally used only in limited data center applications such as connecting servers or switches.
10GBASE-Kx is backplane 10-Gigabit Ethernet and consists of two standards. 10GBASE-KR is a serial standard compatible with 10GBASE-SR, 10GBASE-LR, and 10GBASE-ER. 10GBASE-KX4 is compatible with 10GBASE-LX4. These standards use up to 40 inches of copper printed circuit board with two connectors in place of cable. These very specialized standards are used primarily for switches, routers, and blade servers in data center applications.
10GBASE-T is the 10-Gigabit standard that uses the familiar shielded or unshielded copper UTP cable. It operates at distances of up to 55 meters (180 ft.) over existing Category 6 cabling or up to 100 meters (328 ft.) over augmented Category 6, or “6a,” cable, which is specially designed to reduce crosstalk between UTP cables. Category 6a cable is somewhat bulkier than Category 6 cable but retains the familiar RJ-45 connectors.
To send data at these extremely high speeds across four-pair UTP cable, 10GBASE-T uses sophisticated digital signal processing to suppress crosstalk between pairs and to remove signal reflections.
10-Gigabit Ethernet Applications
> 10-Gigabit Ethernet is already being deployed in applications requiring extremely
> As a lower-cost alternative to Fibre Channel in storage area networking (SAN)
> High-speed server interconnects in server clusters.
> Aggregation of Gigabit segments into 10-Gigabit Ethernet trunk lines.
> High-speed switch-to-switch links in data centers.
> Extremely long-distance Ethernet links over public SONET infrastructure.
Although 10-Gigabit Ethernet is currently being implemented only by extremely high-volume users such as enterprise networks, universities, telecommunications carriers, and Internet service providers, it’s probably only a matter of time before it’s delivering video to your desktop. Remember that only a few years ago, a mere 100-Mbps was impressive enough to be called “Fast Ethernet.”
Black Box Explains...Ceramic and composite ferrules.
Cables manufactured with ceramic ferrules are ideal for mission-critical applications or connections that are changed frequently. These cables are high quality and typically have a very long life. Ceramic ferrules... more/see it noware more precisely molded and fit closer to the fiber than their composite counterparts, which gives them a lower optical loss.
On the other hand, cables with composite ferrules are ideal for less critical applications or connections that won’t be changed frequently. Composite ferrule cables are characterized by low loss, good quality, and long life. collapse
Black Box Explains... Pulling eyes and fiber cable.
Fiber optic cable can be damaged if pulled improperly. Broken or cracked fiber, for example, can result from pulling on the fiber core or jacket instead of the strength member.... more/see it nowAnd too much tension or stress on the jacket, as well as too tight of a bend radius, can damage the fiber core. If the cables core is harmed, the damage can be difficult to detect.
Once the cable is pulled successfully, damage can still occur during the termination phase. Field termination can be difficult and is often done incorrectly, resulting in poor transmission. One way to eliminate field termination is to pull preterminated cable. But this can damage the cable as well because the connectors can be knocked off during the pulling process. The terminated cable may also be too bulky to fit through ducts easily. To help solve all these problems, use preterminated fiber optic cable with a pulling eye. This works best for runs up to 2000 feet (609.6 m).
The pulling eye contains a connector and a flexible, multiweave mesh-fabric gripping tube. The latched connector is attached internally to the Kevlar®, which absorbs most of the pulling tension. Additionally, the pulling eyes mesh grips the jacket over a wide surface area, distributing any remaining pulling tension and renders it harmless. The end of the gripping tube features one of three different types of pulling eyes: swivel, flexible, or breakaway.
Swivel eyes enable the cable to go around bends without getting tangled. They also prevent twists in the pull from being transferred to the cable. A flexible eye follows the line of the pull around corners and bends, but its less rigid. A breakaway eye offers a swivel function but breaks if the tension is too great. We recommend using the swivel-type pulling eye.
A pulling eye enables all the fibers to be preterminated to ensure better performance. The terminated fibers are staggered inside the gripping tube to minimize the diameter of the cable. This enables the cable to be pulled through the conduit more easily. collapse
Black Box Explains...Fiber optic cable construction.
Fiber optic cable consists of a core, cladding, coating, strengthening fibers, and cable jacket.
This is the physical medium that transports optical data signals from an attached light source to... more/see it nowa receiving device. The core is a single continuous strand of glass or plastic thats measured (in microns) by the size of its outer diameter. The larger the core, the more light the cable can carry.
All fiber optic cable is sized according to its cores outer diameter.
The three multimode sizes most commonly available are 50, 62.5, and 100 microns. Single-mode cores are generally less than 9 microns.
This is a thin layer that surrounds the fiber core and serves as a boundary that contains the light waves and causes the refraction, enabling data to travel throughout the length of the fiber segment.
This is a layer of plastic that surrounds the core and cladding to reinforce the fiber core, help absorb shocks, and provide extra protection against excessive cable bends. These buffer coatings are measured in microns (µ) and can range from 250 to 900 microns.
These components help protect the core against crushing forces and excessive tension during installation.
The materials can range from Kevlar® to wire strands to gel-filled sleeves.
This is the outer layer of any cable. Most fiber optic cables have an orange jacket, although some types can have black or yellow jackets. collapse
Black Box Explains...10-Gigabit Ethernet.
10-Gigabit Ethernet (10-GbE), ratified in June 2002, is a logical extension of previous Ethernet versions. 10-GbE was designed to make the transition from LANs to Wide Area Networks (WANs) and... more/see it nowMetropolitan Area Networks (MANs). It offers a cost-effective migration for high-performance and long-haul transmissions at up to 40 kilometers. Its most common application now is as a backbone for high-speed LANs, server farms, and campuses.
10-GbE supports existing Ethernet technologies. It uses the same layers (MAC, PHY, and PMD), and the same frame sizes and formats. But the IEEE 802.3ae spec defines two sets of physical interfaces: LAN (LAN PHY) and WAN (WAN PHY). The most notable difference between 10-GbE and previous Ethernets is that 10-GbE operates in full-duplex only and specifies fiber optic media.
At a glanceGigabit vs. 10-Gigabit Ethernet
• CSMA/CD + full-duplex
• Leveraged Fibre Channel PMDs
• Reused 8B/10B coding
• Optical/copper media
• Support LAN to 5 km
• Carrier extension
• Full-duplex only
• New optical PMDs
• New coding scheme 64B/66B
• Optical (developing copper)
• Support LAN to 40 km
• Throttle MAC speed for WAN
• Use SONET/SDH as Layer 1 transport
The alphabetical coding for 10-GbE is as follows:
S = 850 nm
L = 1310 nm
E = 1550 nm
X = 8B/10B signal encoding
R = 66B encoding
W = WIS interface (for use with SONET).
10GBASE-SR — Distance: 300 m; Wavelength: 850 nm; Cable: Multimode
10GBASE-SW — Distance: 300 m; Wavelength: 850 nm; Cable: Multimode
10GBASE-LR — Distance: 10 km; Wavelength: 1310 nm; Cable: Single-Mode
10GBASE-LW — Distance: 10 km; Wavelength: 1310 nm; Cable: Single-Mode
10GBASE-LX4 — Distance: Multimode 300 m, Single-Mode 10 km; Wavelength: Multimode 1310 nm, Single-Mode WWDM; Cable: Multimode or Single-Mode
10GBASE-ER — Distance: 40 km; Wavelength: 1550 nm; Cable: Single-Mode
10GBASE-EW — Distance: 40 km; Wavelength: 550 nm; Cable: Single-Mode
10GBASE-CX4* — Distance: 15 m; Wavelength: Cable: 4 x Twinax
10GBASE-T* — Distance: 25–100 m; Wavelength: Cable: Twisted Pair
* Proposed for copper. collapse
Fiber optic cable construction and types.
Multimode vs. single-mode
Multimode cable has a large-diameter core and multiple pathways of light. It is most commonly available in two core sizes: 50-micron and 62.5-micron.
Multimode fiber optic cable can... more/see it nowbe used for most general data and voice fiber applications such as adding segments to an existing network, and in smaller applications such as alarm systems and bringing fiber to the desktop. Both multimode cable cores use either LED or laser light sources.
Multimode 50-micron cable is recommended for premise applications?(backbone, horizontal, and intrabuilding connections). It should be considered for any new construction and for installations because it provides longer link lengths and/or higher speeds, particularly in the 850-nm wavelength, than 62.5-micron cable does.
Multimode cable commonly has an orange or aqua jacket; single-mode has yellow. Other colors are available for various applications and for identification purposes.
Single-mode cable has a small (8–10-micron) glass core and only one pathway of light. With only a single wavelength of light passing through its core, single-mode cable realigns the light toward the center of the core instead of simply bouncing it off the edge of the core as multimode does.
Single-mode cable provides 50 times more distance than multimode cable does. Consequently, single-mode cable is typically used in high-bandwidth applications and in long-haul network connections spread out over extended areas, including cable television and campus backbone applications. Telcos use it for connections between switching offices. Single-mode cable also provides higher bandwidth, so you can use a pair of single-mode fiber strands full-duplex at more than twice the throughput of multimode fiber.
Fiber optic cable consists of a core, cladding, coating, buffer strengthening fibers, and cable jacket.
The core is the physical medium that transports optical data signals from an attached light source to a receiving device. It is a single continuous strand of glass or plastic that’s measured (in microns) by the size of its outer diameter.
All fiber optic cable is sized according to its core’s outer diameter. The two multimode sizes most commonly available are 50 and 62.5 microns. Single-mode cores are generally less than 9 microns.
The cladding is a thin layer that surrounds the fiber core and serves as a boundary that contains the light waves and causes the refraction, enabling data to travel throughout the length of the fiber segment.
The coating is a layer of plastic that surrounds the core and cladding to reinforce the fiber core, help absorb shocks, and provide extra protection against excessive cable bends. These coatings are measured in microns (µ); the coating is 250µ and the buffer is 900µ.
Strengthening fibers help protect the core against crushing forces and excessive tension during installation. This material is generally Kevlar® yarn strands within the cable jacket.
The cable jacket is the outer layer of any cable. Most fiber optic cables have an orange jacket, although some types can have black, yellow, aqua or other color jackets. Various colors can be used to designate different applications within a network.
Simplex vs. duplex patch cables
Multimode and single-mode patch cables can be simplex or duplex.
Simplex has one fiber, while duplex zipcord has two fibers joined with a thin web. Simplex (also known as single strand) and duplex zipcord cables are tight-buffered and jacketed, with Kevlar strength members.
Because simplex fiber optic cable consists of only one fiber link, you should use it for applications that only require one-way data transfer. For instance, an interstate trucking scale that sends the weight of the truck to a monitoring station or an oil line monitor that sends data about oil flow to a central location.
Use duplex multimode or single-mode fiber optic cable for applications that require simultaneous, bidirectional data transfer. Workstations, fiber switches and servers, Ethernet switches, backbone ports, and similar hardware require duplex cable.
PVC (riser) vs. plenum-rated
PVC cable (also called riser-rated cable even though not all PVC cable is riser-rated) features an outer polyvinyl chloride jacket that gives off toxic fumes when it burns. It can be used for horizontal and vertical runs, but only if the building features a contained ventilation system. Plenum can replace PVC, but PVC cannot be used in plenum spaces.
“Riser-rated” means that the jacket is fire-resistant. However, it can still give off noxious fumes when overheated. The cable carries an OFNR rating and is not for use in plenums.
Plenum-jacketed cables have FEP, such as Teflon®, which emits less toxic fumes when it burns. A plenum is a space within the building designed for the movement of environmental air. In most office buildings, the space above the ceiling is used for the HVAC air return. If cable goes through that space, it must be “plenum-rated.”
Distribution-style vs. breakout-style
Distribution-style cables have several tight-buffered fibers bundled under the same jacket with Kevlar or fiberglass rod reinforcement. These cables are small in size and are typically used within a building for short, dry conduit runs, in either riser or plenum applications. The fibers can be directly terminated, but because the fibers are not individually reinforced, these cables need to be terminated inside a patch panel, junction box, fiber enclosure, or cabinet.
Breakout-style cables are made of several simplex cables bundled together, making a strong design that is larger than distribution cables. Breakout cables are suitable for riser and plenum applications.
Loose-tube vs. tight-buffered
Both loose-tube and tight-buffered cables contain some type of strengthening member, such as aramid yarn, stainless steel wire strands, or even gel-filled sleeves. But each is designed for very different environments.
Loose-tube cable is specifically designed for harsh outdoor environments. It protects the fiber core, cladding, and coating by enclosing everything within semi-rigid protective sleeves or tubes. Many loose-tube cables also have a water-resistant gel that surrounds the fibers. This gel helps protect them from moisture, so the cables are great for harsh, high-humidity environments where water or condensation can be a problem. The gel-filled tubes can also expand and contract with temperature changes. Gel-filled loose-tube cable is not the best choice for indoor applications.
Tight-buffered cable, in contrast, is optimized for indoor applications. Because it’s sturdier than loose-tube cable, it’s best suited for moderate-length LAN/WAN connections, or long indoor runs. It’s easier to install as well, because there’s no messy gel to clean up and it doesn’t require a fan-out kit for splicing or termination.
Indoor/outdoor cable uses dry-block technology to seal ruptures against moisture seepage and gel-filled buffer tubes to halt moisture migration. Comprised of a ripcord, core binder, a flame-retardant layer, overcoat, aramid yarn, and an outer jacket, it is designed for aerial, duct, tray, and riser applications.
Interlocking armored cable
This fiber cable is jacketed in aluminum interlocking armor so it can be run just about anywhere in a building. Ideal for harsh environments, it is rugged and rodent resistant. No conduit is needed, so it’s a labor- and money-saving alternative to using innerducts for fiber cable runs.
Outside-plant cable is used in direct burials. It delivers optimum performance in extreme conditions and is terminated within 50 feet of a building entrance. It blocks water and is rodent-resistant.
Interlocking armored cable is lightweight and flexible but also extraordinarily strong. It is ideal for out-of-the-way premise links.
Laser-optimized 10-Gigabit cable
Laser-optimized multimode fiber cable assemblies differ from standard multimode cable assemblies because they have graded refractive index profile fiber optic cable in each assembly. This means that the refractive index of the core glass decreases toward the outer cladding, so the paths of light towards the outer edge of the fiber travel quicker than the other paths. This increase in speed equalizes the travel time for both short and long light paths, ensuring accurate information transmission and receipt over much greater distances, up to 300 meters at 10 Gbps.
Laser-optimized multimode fiber cable is ideal for premise networking applications that include long distances. It is usually aqua colored.
Black Box Explains...How fiber is insulated for use in harsh environments.
Fiber optic cable not only gives you immunity to interference and greater signal security, but it’s also constructed to insulate the fiber’s core from the stress associated with use in... more/see it nowharsh environments.
The core is a very delicate channel that’s used to transport data signals from an optical transmitter to an optical receiver. To help reinforce the core, absorb shock, and provide extra protection against cable bends, fiber cable contains a coating of acrylate plastic.
In an environment free from the stress of external forces such as temperature, bends, and splices, fiber optic cable can transmit light pulses with minimal attenuation. And although there will always be some attenuation from external forces and other conditions, there are two methods of cable construction to help isolate the core: loose-tube and tight-buffer construction.
In a loose-tube construction, the fiber core literally floats within a plastic gel-filled sleeve. Surrounded by this protective layer, the core is insulated from temperature extremes, as well as from damaging external forces such as cutting and crushing.
In a tight-core construction, the plastic extrusion method is used to apply a protective coating directly over the fiber coating. This helps the cable withstand even greater crushing forces. But while the tight-buffer design offers greater protection from core breakage, it’s more susceptible to stress from temperature variations. Conversely, while it’s more flexible than loose-tube cable, the tight-buffer design offers less protection from sharp bends or twists. collapse