Simplifying the Migration from Copper to Fiber White Paper
Abstract - With transmission speeds for HD video and 4K pushing copper to its limits, optical fiber solutions have become the obvious alternative for video transmission and the smooth transition of infrastructure to IP video. But despite the known advantages of optical fiber, many engineers and network managers are reluctant to make the move from copper to fiber, based on concerns over the cost and perceived complexities of an optical fiber infrastructure. Developing a fiber optic network is less daunting than many may expect. The authors, highly experienced in both copper and optical fiber technologies in the broadcasting arena, will lay many of these concerns to rest. New and advanced factory pre-terminated plug-and-play optical fiber and connectivity solutions provide a simple, cost effective, and more reliable migration path, while preparing the facility s infrastructure for the even higher data rates and bandwidth demands of the future. Introduction For years, broadcast network infrastructures have relied on copper for video transmission. However, driven by the demands for HD video transport and yet to be determined emerging technologies, today s broadcast facility faces explosive bandwidth demands and needs an infrastructure capable of handling higher and higher data rates. The advantages of fiber over copper, total cost of ownership, and factory pre-terminated cables with plug-and-play solutions will be explored providing engineering managers the basic information for developing a scalable, reliable, and flexible fiber optic infrastructure capable of handling current needs, while being futureproofed for years to come. Where Broadcasting is Now and What to Expect Uncompressed 1080i HD has a data rate of 1.5Gb/s. Copper is capable of transporting this signal for only about 100-130 meters, requiring expensive equipment to re-clock the signal on longer runs. With 4K on the horizon, engineers confront data rates of up to 12Gb/s. This, along with the promise of video as IP, which can combine multiple videos on a single path, means higher data rates that are beyond the capabilities of copper. As technology evolves, so must the broadcast network infrastructure that supports those technologies. Copper cabling is at or near its limits and not capable of meeting the IP and HD video requirements of the future. An examination of the attributes of optical fiber and copper assists in the further understanding of the advantages of fiber over copper. Advantages of Fiber Over Copper Higher data rates: Copper has reached its limit at 1.5Gb/s. The future, with higher resolutions, 3D, and video as IP, requires data rates of up to12gb/s and beyond Longer distance: At 1.5Gb/s copper reaches its limit at about 130 meters. Fiber can go much farther. A fiber infrastructure will provide a smooth transition to video as IP Fiber, with its high bandwidth capabilities, has the ability to combine multiple signals and channels on a single fiber; important for IP video transmission Reduced labor costs when deploying a factory terminated plug-and-play optical fiber solution Optical fiber cables are lighter and have a smaller diameter than copper for high density applications and better cable management 2
Cost of Fiber When comparing the cost of copper versus fiber, a common error is to consider only one part of the cost, specifically the cost of converting from electrical to optical and then back to electrical. An accurate cost comparison must consider the Total Cost of Ownership (TCO). When all the costs are compared, it can be seen that implementing fiber becomes very cost effective due in large part to increased competition and technological advancements that have steadily decreased costs for optical fiber. A TOC analysis should include the following costs: Copper: Cable Connectors Labor to install the cable Labor to install connectors Value of the cable trays Equipment to re-clock the signal (as needed for longer runs) Fiber: Pre-terminated fiber assemblies (typically 12, 24, or 48 strands) Labor to install the fiber Value of the cable trays Fiber breakout bulkheads Fiber jumpers between the main fiber run and the converters The electrical/optical converters In actuality, the additional costs of fiber converters and breakout panels are often offset by the lower cable costs, less labor (e.g. plug-and-play approach), and eliminating the need for reclocking equipment. Another item often missed in costing are the cable trays, which have a significant value. Although projects typically are able to use existing cable trays, they are still resources that should be accounted for and included in the total cost. The TOC approach often reveals that a fiber infrastructure is not as expensive as previously thought and in many cases can be less expensive than copper. Consideration in Selecting the Right Fiber Single-Mode or Multimode Single-mode fiber (SMF) has astonishing properties and its 9 micron small core eliminates modal dispersion, enabling tremendous transmission and bandwidth capacity over very long distances when compared to multimode fiber (MMF). In broadcasting, this fiber is typically used for: Transporting video Transporting video between buildings or from arena to truck for productions, satellite, uplinks etc. Transporting video point to point for breakouts (from SMPTE fiber) Excellent for futureproofing the broadcast network and data center Many engineers and broadcast network experts recommend using single-mode fiber wherever possible, even for short distances due to the fiber s outstanding transmission properties. Multimode fiber is used most often for shorter distance applications. Unlike SMF, MMF has a larger core and increased modal dispersion, limiting its bandwidth capacity and distance/reach. One advantage is that it can use relatively low cost transmitters, such as an 850 nm laser called a VCSEL (vertical cavity surface-emitting laser). 3
OM1 62.5/125µm fiber and even OM2 50/125µm fiber are today considered legacy with the advent of OM3 50µm and OM4 50µm laser optimized multimode fiber (LOMMF). OM4 is used primarily in very high-speed networks. For broadcasting, OM3/OM4 is commonly used in the IP environments, such as for storage, playout servers, and graphics. Multimode considerations include: Lower cost transmitters MMF is less vulnerable to dust and used in harsher environments IEEE 802.3bm recently approved OM4 support of 100GBASE-SR4 at 100m. (70m over OM3) 4x25G optical interface for MMF; Reduces cost (reduce lane count and complexity); utilizes 8 MM fibers; facilitates easy migration to 40 Gb/s. Grade Bandwidth at 850 with EMB 1 GbE Distance 10 GbE Distance 40/100 GbE Distance Jacket Color OM1 200 MHz km 300 meters 36 meters N/A Orange OM2 500 MHz km 550 meters 86 meters N/A Orange OM3 2000 MHz km 1 km 300 meters 100 meters Aqua OM4 4700 MHz km 1 km 550 meters 125 meters Aqua Some considerations to keep in mind when using optical fiber include: SMF and MMF are not compatible Transmitters and receivers are typically designed for either MMF or SMF. The fiber used should match. Cannot mix MMF and SMF between two endpoints Optical Fiber Cable Types Fiber is available in many different configurations; selection depends on the individual installation. The cables listed below represent only a sample of available cable types. Depending on the installation s physical and environmental requirements, fiber is available in loose tube, armored, riser, tactical, and plenum rated constructions to name a few. Fiber optic cable is also available with bend-insensitive fiber (BIF) and offered in a wide range of fiber counts. Loose tube cables: This small, high fiber count cable is composed of several fibers together inside a small plastic tube, which are wound around a central strength member and jacketed. The cable is ideal for outside plant trunking applications, since it can be made with the loose tubes filled with gel or water absorbent powder to prevent harm from water. Available in gel and gel free construction, it can be used in conduits, strung overhead, or buried directly into the ground. Since the fibers have only a thin buffer coating, they must be carefully handled and protected to prevent damage. Ribbon cables: Ribbon cables allow quick and easy fiber access, often by hand, eliminating the need for special tools. Fibers are easily exposed by bending the fiber ribbon, releasing the matrix material, and freeing the fibers. The fibers come away from the ribbon matrix cleanly, thereby limiting potential problems for easy mass splicing of up to 12 fibers that saves time and labor. Typically, ribbon cables can be used for the same applications as loose tube cables. Loose tube cables can be ribbonized, making the two constructions compatible. Blown Fiber: Used in larger buildings (e.g. stadiums, campus wide backbones etc.), blown fiber is installed in areas where change is expected to accommodate future technologies, or in situations where changes or additional pulls of fiber would be disruptive to existing operations and systems. Unlike conventional cable, a rugged tube with a number of smaller internal tubes is first run between the various sites. Once the master tubes are installed, multi-strand fiber is then blown through the individual smaller tubes as needed with a minimum of effort utilizing dry nitrogen. Simplex/Zip Cord: These cables have one or two strands of fiber and are tight-buffered (coated with a 900 micron buffer over the primary buffer coating) with aramid fiber strength members and jacketed for indoor use. Zip cord is simply two of these joined with a thin web. It s used mostly for patch cord and backplane applications, but zip cord can also be used for desktop and in-console connections. Distribution/Trunk Cables: These cables contain several tight-buffered fibers bundled under the same jacket with strength members or fiberglass rod reinforcement to stiffen the cable and prevent kinking. These cables are small in size and used for short, dry, conduit runs and for 4
riser and plenum applications. The fibers are double buffered and can be directly terminated, but because their fibers are not individually reinforced for protection, these cables need to be broken out with a breakout box or terminated inside a fiber tray, patch panel or junction box. Breakout Cables: Constructed of several simplex cables bundled together, this cable features a strong, rugged design, but is larger and more expensive than the distribution cables. It is suitable for conduit runs, riser and plenum applications. Because each fiber is individually reinforced, this design allows for quick termination to connectors and does not require patch panels or boxes. Breakout cables can be more economical when fiber count isn t too large and distances too long, because it requires much less labor to terminate. Breakout cable is typically utilized where 19 panels exist and when the panels may be frequently moved or disturbed. Another option is the use of pre-terminated MPO to LC adapters (hydra cables) or MPO to LC cassettes. Factory pre-terminated fiber assemblies: Factory terminated cable (single or multi-strand) can be used for fiber trunks, as well as for patch cords in most cases. They provide for easy installation, quick termination, and do not require expensive investment in tools and technical expertise. Connector Types The types of fiber connectors most appropriate for broadcast include: SC: The SC connector offers excellent loss characteristics and comes in a standard footprint. It is easy to snap in and remove. The SC is pull-proof and is available in UPC and APC styles. LC: The LC comes in a small-form-factor. The LC features are similar to SC, but its size allows double the density. Available in UPC and APC. MPO: Multi-fiber Push On is a highly reliable multiple fiber connector that typically comes in 12 fiber and 24 fiber configurations for multi-fiber applications. MPO cable assemblies play a role in plug-and-play infrastructure design and are discussed in greater length in upcoming sections. Different Approaches for Building/Installing Your Fiber Infrastructure There are three primary approaches to building your fiber optic infrastructure: In-house field cabling and terminations, integrator field cabling and terminations, and factory pre-terminated or pre-connectorized assemblies/plug-and-play. Each has its advantages and disadvantages. In-House Field Termination In this approach, the broadcast company uses direct employees who are responsible for infrastructure design, installation, and maintenance. Advantages: In-house expertise of the infrastructure Timely installations Service availability Highly skilled workforce Disadvantages: Requires the purchase of expensive equipment to terminate fibers Requires highly skilled workforce and continued training and education Integrator/Contractor Termination This approach includes the contracting of outside installer/contractors. Advantages: Use of skilled installers with expertise in installing and terminating fiber Eliminates the cost expensive tools and maintaining a skilled workforce Disadvantages: Lose control of knowledge of infrastructure Can be expensive Dependency on an outside contractor 5
Pre-terminated Assemblies and Plug-and-Play This approach uses pre-terminated cables from the factory Advantages: Factory terminations are higher quality than field terminations Simplifies installation, which reduces labor costs Does not require technical expertise Disadvantages: Factory cables can be more expensive Non-standard cable runs (e.g. trunk cables) must be custom made To fully understand the advantages of plug-and-play, the approach will be examined in more detail in the next section. Building an Optical Fiber Infrastructure with Factory Pre-terminated and Plug-and-Play Solutions For those engineers and managers who want a stress-free and easy solution for integrating an optical fiber infrastructure into their facilities, using factory pre-connectorized cable assemblies and plug-and-play techniques is the best approach. Unlike terminating fiber in the field, pre-connectorized cable assemblies and patch cords are guaranteed to work out of the box to the highest performance specifications. Under the best circumstances, field-terminated cables offer 0.5 to 0.25 db signal loss, while factory pre-terminated fiber delivers typical loss of less than 0.2 db. Factory termination will provide consistent loss values, thereby maximizing reliability and performance. The labor savings associated with using factory pre-terminated cables in most instances makes it a more economical solution than field termination of fiber cables. Factory pre-terminated cables not only eliminate the labor costs associated with installing connectors in the field, they also do away with the need to spend money on redoing work that has failed, as well as the cost to purchase additional connectors. Factory pre-terminated cable comes from the manufacturer where it was prepared under the supervision of fiber optic experts in an environmentally controlled setting with quality inspection and testing. Connectors are attached to individual strands of fiber in an automated factory process that is not as subject to human error. Once attached to the fiber cable, the connections are tested to ensure quality and performance. However, relying on factory pre-terminated cable requires some forethought and planning. Planning in advance to determine where panels will be located and the length of the trunk cable runs is necessary. Depending on the manufacturer, factory pre-terminated cable assemblies are available in almost any combination of cable types and connectors. For the plug- and- play high data rate optical fiber infrastructure solution, LC and MPO assemblies are the most recommended. Factory preconnectorized cables can plug together with the simplicity of plugging in an Ethernet cable. Integrating the High Data Rate Fiber Infrastructure: 12-24 Fiber Plug-and-Play Solution Integrating a high data rate broadcast optical fiber infrastructure is easy and cost effective. An innovative solution utilizing 12 or 24 fiber trunk cables, MPO connectivity, patch cords, and breakout cassettes creates a dynamic, futureproofed system that provides a migration path to higher data rates for higher resolutions and IP transport with 10/40/100GbE. Using a 12 or 24-fiber trunking and interconnect solution allows broadcast network managers to easily expand and adapt their infrastructures to meet future needs. 6
Why use 12 and 24-Fiber Trunk Cables? While many solutions on the market recommend the use of 12-fiber multimode trunk cables between core areas, the 24-fiber MPO trunking solution is an attractive option. In this scenario, factory pre-terminated 24-fiber trunk cables with 24-fiber MPOs on both ends are connected to breakout boxes, which then use fiber jumpers to feed either the video electrical/ optical converters or data routers, thereby providing an excellent solution with return on investment and reduced installation expense. However, the use of 12 fibers is still a viable alternative. Consider the future promise of transporting video as IP; such a system might well use 40Gb/s links. A single 40-GbE link requires 8 strands; 3 paths will use all of the fibers in a 24 strand trunk cable. If a12-fiber cable solution were used, there would be wasted fiber, using only 8 of the 12 fibers for a single path. Three 40-GbE links as described would require three separate 12-fiber trunk cables, resulting in a total of 12 unused fibers (or 4 unused fibers for each trunk). Additional benefits of using 24-fiber trunk cables are reduced cable congestion and lower installation labor costs. FIG.1 Hydra cable with a 24-fiber MPO on one end and 12 duplex LCs on the other end The facility s fiber trunking and interconnect solution consists of the 24-fiber trunk cables between equipment distribution areas. Within the rack or cabinet, breakout cassettes or hydra cables transition from the multi-strand MPO connector to individual fiber strands for local distribution. The Easy, Cost Efficient Migration Path The 24-fiber data center fiber trunking and interconnect solution offers a simple and costeffective migration path from 10-GbE to 40- and 100-GbE, providing future readiness for three generations of active equipment. With 24-fiber trunk cables effectively supporting all three applications, there is no need to re-cable the pathways from the back of the switch panel to the equipment distribution area; all that cabling remains permanent and never has to be touched. That means that data center managers can easily migrate to higher speeds, with less time and complexity. With 24-fiber trunk cables that offer guaranteed performance for 10-, 40- and 100- GbE, upgrading the cabling infrastructure is as simple as upgrading the hydra cables or cassettes and patch cords to the equipment. or 100G* or 100G* 100G 100G *100G implemented as 4x25G 100G implemented as 10x10G 7
Conclusion For broadcasting, it is not a matter of whether to integrate a high data speed, bandwidth-rich ready optical fiber infrastructure, but when. The broadcast facility must be ready to meet the speed of emerging technologies and the quick advances in IP and HD video. Copper just can t handle the technological future. There are many ways to build a fiber infrastructure. Concerns over cost and complexity have been demystified. Simply put, building an optical fiber infrastructure can be cost efficient, hasslefree and easy by deploying a 12 or 24-fiber trunking and interconnect plug-and-play solution a solution that prepares broadcasters for even 8k and beyond. www.commscope.com Visit our website or contact your local CommScope representative for more information. 2016 CommScope, Inc. All rights reserved. All trademarks identified by or are registered trademarks or trademarks, respectively, of CommScope, Inc. This document is for planning purposes only and is not intended to modify or supplement any specifications or warranties relating to CommScope products or services. WP-322924-AE (04/16)