Category Archives: Cabling Solutions

40G Deployment: The Cost Difference Between SMF and MMF

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40G network are now being extensively adopted within LANs and data centers. 100G is still predominantly in the carrier network, but could soon extend its stretch to your local network. There exists much confusion as to whether to choose single-mode fiber (SMF) or multimode fiber (MMF) for deploying 40G bandwidth, and how to get fully prepared for scaling to higher-speed 100G. If you are hesitating to make the choice, you may find this article helpful.

MMF optics and SMF optics cost

Multimode Fiber (MMF): Cost-effective With Higher Tolerance to Dirt

Cost-effectiveness: Multimode fiber (MMF) has been evolving to handle the escalating speed: OM3 has been superseded by OM4 and OM5 is there ready to use. MMF has a wider array of short distance transceivers that are easier to get. One of the liable argument that in favor of using MMF is that multimode optics use less power than single-mode ones, but only in condition that you have tens of thousands of racks. In essence, MMF still has its position under certain circumstances, like cabling within the same rack, in Fiber Channel and for backbone cabling in some new construction buildings.

cost-effective multimode fiber solution

Tolerance to Dirt: Multimode fiber tends to have a lot more tolerance to dirty connections than single-mode fiber. It can handle very dirty couples or connectors to ensure reliable and consistent link performance. Besides, it is easy to terminate, and more accommodating bend radius. So MMF is preferred by links that change frequently or are less than permanent.

multimode fiber MMF advantage in data center

Single-mode Fiber (SMF): Higher Capability and Better Future-proofing

Speed capability: Capacities are really vital for network growth. SMF does so with relatively larger capability than that of MMF. The gap between SMF and MMF cabling is much wider for high-density, high-speed networks. If you want to go further with SMF, say scaling to 100G or beyond, you simply need to upgrade the optics. Unlike using MMF, in which you have to upgrade the glass (OM3 to OM4 to OM5), the labor cost concerning this cannot be underestimated. The capacity for scaling of SMF alone makes it worth the cost. You can use single-mode for almost everything, no need for media conversion. SMF offers enough bandwidth to last a long time, making it possible to upgrade 100 Gbps to Tbps with CWDM/DWDM.

single-mode fiber SMF advantage

Future proofing: Despite the fact that SM optical transceivers usually cost higher than MM optics, SMF cabling is cheaper and can support much longer distance and reliable performance. Not to mention that bandwidth on SMF keeps going up and up on the same old glass. The good news is that the cost of SMF is dropping in recent years, and it is redesigning to run with less power, thus advocators of SMF think that it is pretty much the only rational choice for infrastructure cabling and the sure winner for today and tomorrow.

SMF and MMF: A Simple Comparison of Cost

There is no doubt that SMF is a better investment in the long run, but MMF still has a long way to go in data center interconnections. In fact the price difference of SMF optics and MMF optics can be minimized if you choose the right solution. Assuming to connect two 40G devices at 70 m away, let’s see the cost of SMF and MMF in the following chart.

Module Connector Type SMF or MMF Price 2 Connections 4 Connections 6 Connections
40GBASE-SR4 MPO12 MMF, OM4 $49.00 $564.48 $1128.96 $1693.44
40GBASE-BiDi LC MMF, OM4 $300.00 $1534.24 $2734.24 $3934.24
40GBASE-LR4 LC SMF, OS2 $340.00 $1,609.84 $2,969.84 $4,329.84
80 Gbit 160 Gbit 240 Gbit

 

Conclusion

Choosing the right fiber for your network application is a critical decision. Understanding your system requirements in order to select the appropriate fiber will maximize the value and performance of your cabling system. Be sure to select the right cable on the basis of aspects including link length, performance, and of course costs. FS provides a broad range of 40G optical transceivers and fiber patch cables with superior quality and fair price. For more details, please visit www.fs.com.

Connectivity Options Comparison for 10G Servers/Switches Networking

Much of the enterprise market is still running on 1GbE speeds and will be looking to migrate to 10GbE over the next several years. As we know, usually there are three types of connections between switches and servers in 10G networking—SFP+ DAC, fiber cables with SFP+ optics, and 10GBASE-T. And in theses connections, network interface card (NIC), also called network adapter, plays an paramount role. In this post, three connections that upgrade to 10G networking will be explored in details.

Connectivity Options

Today, IT managers can select 10GbE interconnect and switch options based on specific intended uses—using copper or fiber cables. Each has advantages and disadvantages. Here are the three connection options.

Fiber Cables with SFP+ Transceiver

Fiber optic connections are well suitable for areas that have heavy traffic aggregations like EoR (End of Row) switches. In these connections, SFP+ modules are used together with fiber patch cables, just like the following picture shows. In some SFP+ connections, SFP+ NIC is also needed to link servers and switches such as in MoR (Middle of Row) or EoR (End of Row) connections. Though cabling with fiber is great for latency and distance (up to 300m), it also costs more.

fiber

SFP+ Direct Attach Copper Cable (DAC)

Connections with DACs are a good choice for deploying 10GbE within blade server enclosures or racks over short distances. But its reach is limited to 7m and it is not backwards-compatible with existing GbE switches. Of course, an add-in 10GBASE NIC is required for these connections.

dac

10GBASE-T NIC (Network Interface Card)

Nowadays, IT managers have 10GBase-T as a third option for either ToR switch or EoR usage models. 10GBASE-T with Cat 6a UTP cabling makes 10GbE available to a much broader market at a lower cost. It offers the most flexible solution for more data center 10GbE networking applications. Besides, 10G SFP+ copper transceiver also uses Cat 6a or Cat 7 copper cables, but it only supports link length of 30 meters.

10GBASE-T NIC

Comparison

As have mentioned above, 10G connections between servers and switches can be realized with both fiber and copper cables. Here is a simple comparison chart.

10G network

No matter fiber cable, 10G SFP+ copper cable or 10GBASE-T NIC, they can be used in ToR, EoR and MoR connections. Apart from the difference listed in the chart, another factor that should be considered is the cost. Even if the fiber cable has advantages on distance and latency, the use of SFP+ transceiver can add up to 30%-40% to server, switch and storage interface costs. And more SFP+ connections mean more add-in network adapters, which add cost and maintenance overhead.

While the raw cost of the 10GBASE-T is far less than either optical fiber or direct attach twinax copper cables. Cat 6a cable is easy to install and maintain, allowing for customized length, and it can be field installed. The most important point is that Cat 6a cable is compatible with existing 1GbE switches. Many networks today already have Cat 6 or Cat 6a cabling in place, so they are 10GBase-T ready. And today’s 10GBase-T network adapters are also cost-effective, enhancing the adoption of 10GBASE-T NIC.

Summary

10G Ethernet is no longer limited to fiber optic media. DAC cable is a popular choice for short distances; 10GBASE-T allows for more economical and easier deployment than ever before. With the price of 10GbE network getting more affordable than ever, many IT managers are sizing the opportunity to upgrade their networks and keep pace with these increasing bandwidth demands. After reading this post, fiber or copper, which would you choose?

Different Applications for 10G SFP+ Cables

10G SFP+ optics are of various kinds, including DACs, AOCs, and other 10G SFP+ optics (10GBASE-SR/LR/ER/ZR and 10GBAE-T copper transceivers) plus patch cables and copper cables, which are widely adopted in data centers to connect servers, storage appliance and switches. Each of them has different application for different distance. Next, we will talk about these cables respectively.

10G DAC: Server to Switch Connectivity

Direct attach cable (DAC) is a type of sheathed high-speed cable featuring SFP connectors on either termination. The main utility of direct attach cables lies in connecting server to switch within the rack. Top-rack interconnections in data centers are made of 10g direct attach cables these days to provide better alternative to RJ 45 connectors, which are losing their foothold because of the bulkier interface and availability of very few equipment and protocol appearing in their compatibility matrix. For any short range connection measuring as small as 5 m to 10 m, a better performing direct attach cable offers easier and more affordable solution. Servers are typically connected to a switch within the same racks. DAC supports link length up to 7 m, making it perfect for servers to switch connections.

FS 10G DACs are available with different lengths with customized services being offered too. And every cable is individually tested on corresponding equipment such as Cisco, Arista, Juniper, Dell, Brocade and other brands, having passed the monitoring of FS intelligent quality control system. Part of the products are shown in the picture below.

10G AOC: Switch to Switch Connectivity

10G active optical cable (AOC) assemblies are high performance, cost effective I/O solutions for 10G Ethernet and 10G Fibre Channel applications, which can also be used as an alternative solution to SFP+ passive and active copper cables while providing improved signal integrity, longer distances, superior electromagnetic immunity and better bit error rate performance. They allow hardware manufactures to achieve high port density, configurability and utilisation at a low cost and a reduced power budget. Unlike DAC, which is often applied in short distance, AOC can achieve transmission distance up to 100 m, so they often used in switch to switch connections.

Servers or Switch to Switch Connectivity

FS active optical cable (AOC) assemblies use active circuits to support longer distances than standard passive or active SFP+ Copper Cables. FS offers Cisco compatible AOC which is designed for high speed, short range data link via optical fiber wire.

10G SFP+ Optics: Server/Storage to Switch Connectivity

10G SFP+ transceivers, including 10GBASE-SR/LR/ER/ZR and 10GBAE-T copper transceiver, are designed for CWDM and DWDM applications. The range of transceivers supports 850nm, 1310nm, 18 channel for CWDM applications and 40 channels for DWDM applications. These optical transceivers are available with short haul or long haul receivers. Since server or storage to switch connection requires reliable, scalable and high-speed performance, transceivers plus patch cables are usually adopted to achieve such a connection.

Server or Storage to Switch Connectivity

FS 10G transceivers are of various types, including GBIC, SFP+, XFP, X2, XENPAK optics, which can be deployed in diverse networking environments. With an industry-wide compatibility and strict test program, FS 10G SFP+ modules can give customers a wide variety of 10 Gigabit Ethernet connectivity options such as server/storage to switch connectivity.

Conclusion

Different cables are selected for different distance and application. Generally speaking, 10G DAC is perfect for short reach applications within racks, while AOCs are suitable for inter-racks connections between ToR and EoR switches. With excellent quality and lifetime warranty, FS 10G optics brings real-time network intelligence to the financial services market at 10 Gbps speeds. All the products mentioned in the previous text are in stock. For more information, please visit us at www.fs.com.

Wideband Multimode Fiber: What to Expect From It?

Multimode fiber (MMF) holds a major position in local area network (LAN) backbone cabling and data center due to its capability to transmit high data rates at relatively low cost. MMF has evolved now to support multi-gigabit transmission using 850 nm VCSEL (vertical cavity surface emitting laser) sources, and the channel capacity of which is greatly improved with the use of parallel transmission over multiple strands of fiber. Wideband multimode fiber (WBMMF), known as OM5, lately comes into our horizon as an alternative to support the escalating data rate and higher bandwidth. Then what can we expect from using WBMMF? This article may give you some hints.

Existing Problems of Multimode Fiber

OM1 and OM2 MMF are developed with the intention to support Fast Ethernet, which fail to support 10 Gbps and 25 Gbps data transmission rates. Hence they are not suggested for new installations. Laser-optimized OM3 and OM4 MMF now play a dominant role in 10G, 40G and 100G Ethernet cabling. However, the demand for bandwidth accelerates so fast, and the VCSEL-based transceiver technology cannot keep pace. Consequently, it’s getting more costly for fiber cabling systems to support next-generation Ethernet migration.

Wideband Multimode Fiber: Taking New Wavelength to Multimode Fiber

Wideband multimode fiber (WBMMF) is designed to carry multiple short wavelength signals that can be aggregated for high bandwidth applications–—a technology known as wavelength division multiplexing (WDM). Unlike conventional multimode fiber that optimally supports a single wavelength, WBMMF can accommodate multiple wavelengths, enabling these multiple wavelengths to simultaneously travel along a single fiber strand.

wideband multimode fiber

In this way, WBMMF increases each fiber’s capacity by at least a factor of four, allowing at least a fourfold data-rate increase, or a fourfold reduction in the number of fibers. That means, when transmitting four optical signals, instead of using four separate fibers, WBMMF can send down these signals on one fiber over four separate operating windows. For example, 400GbE could be accomplished with 4Tx and 4Rx fibers (today 400GbE over multimode requires 16Tx and 16Rx fibers).

Highlights of Wideband Multimode Fiber

So, what makes WBMMF standing out from other multimode fibers? Besides that it increases MMF’s utility and extends MMF’s value to customers, WBMMF also has the following advantages:

    • WBMMF can support wavelength division multiplexing (WDM) across the 840-953nm wavelength range, at 30nm intervals.

WBMMF wavelength

  • The fiber geometry of WBMMF stays the same as existing OM4 fibers, therefore it is backward compatible with OM4 multimode fiber at 850 nm, making it feasible to retain legacy application support of OM4.
  • WBMMF reduces fiber count by a faction of four, but increases capacity to over 100 Gb/s per fiber, enabling Ethernet 100G-SR, 400G-SR4, 1600G-SR16 and Fiber Channel 128G-SWDM4.
Applications of WBMMF: Short Wavelength Division Multiplexing (SWDM)

WBMMF provides better performance for applications using WDM technology. As the parallel multimode fiber MPO cabling is considerably more costly than the multimode fiber LC-duplex patch cord, WBMMF made it possible to use a single pair of LC fiber instead of MPO trunks in direct point-to-point connection. Which helps to reduce fiber count by transmitting multiple wavelengths in the same multimode fiber, and to keep the overall cabling costs to the minimum.

WBMMF and SWDM

Conclusion

Wideband multimode fiber is a reliable medium to expand your data center or enhance network capacity. With the capability of managing multiple wavelengths, it effectively reduces the number of fibers and enhances total channel capacity, proven to be a cost-effective solution for increasing network bandwidth, and to keep pace with the escalating data demands.

Why Is Plenum Cable Important to High Density Data Centers?

In most terrible building or house fire disasters, combustible plastics (PVC) used in the wiring are always among the very things that contribute to the rapid spread of fire and toxic smoke. And the air conditioning systems even help the toxic smoke given off by the burning cables to spread throughout the building quickly. As for the high density data center with high speed computing equipment and large amount of plastic jacketed cables, it is crucial to take measures to reduce the damage in an unwanted fire. How to make the crucial data center a safer place? The high quality plenum cable (eg. MTP fiber) can be one of the best choices.

break-down of precision air conditioning system might lead to fire incident

The break-down of precision air conditioning system might lead to fire incident.

Plenum Cable for Data Center Environment

Plenum space is an area used for return of air circulation or air conditioning systems. In a data center, the spaces covered by the precision air conditioning unit are often necessary to deploy plenum products. They include not only plenum containment that separates cold aisle and hot aisle, but also plenum cables that meet the highest fire code requirements. Both electric cables and fiber optic cables are required to be plenum rated (CMP) when they are installed in inner walls and inner ceilings of data center buildings.

Cold aisle containment (left) and hot aisle containment (right) in a precision air conditioning unit.

Cold aisle containment (left) and hot aisle containment (right) in a precision air conditioning unit.

MTP Plenum Fiber: Get Safety and High Bandwidth at the Same Time

The integration of plenum jacket and MTP fiber is a perfect solution for high density data center applications. The safety feature of the plenum cable and the high fiber port count of MTP connector endow the data center with two essential components. By using MTP plenum cable, the possible danger that might be caused by cables located at cold aisle and hot aisle can be minimized when a fire incident occurs. In addition, the high bandwidth demands within a limited space in data center can be satisfied.

safe and high speed mtp plenum cable

Use MTP plenum cable to get safety and high bandwidth at the same time.

When buying MTP fibers, be sure to check if it is genuine plenum rated and the MTP connector should meet the physical connection standard for acceptable insertion loss. When burnt, plenum cable will give off little smoke, and the color of the smoke is light instead of dark. FS MTP plenum cables are made of Corning fiber and U.S. Conec MTP connector. They are all tested and guaranteed by 3D interferometry and the insertion loss is no more than 0.35 dB. No matter it is the plenum jacket, the inner fiber, the connector, or the end face geometry, they are all genuine parts and in high quality. They can be checked by any user without a problem.

FS high quality MTP plenum cable made of U.S. Conec connector and Corning fiber.

FS high quality MTP plenum cable made of U.S. Conec connector and Corning fiber.

The Evolution of Data Center Switching

Today, the traditional three-tier data center switching design has developed as a mature technology which had been widely applied. However, with the rapid growth in technology, the bottlenecks and limitations of traditional three-tier architecture keep emerging and more and more network engineers choose to give up such a kind of network architecture. So what’s the next best option for data center switching? The answer is leaf-spine network. For many years, data center networks have been built in layers that, when diagrammed, suggesting a hierarchical tree. As this hierarchy runs up against limitations, a new model is taking its place. Below, you will see a quick comparison between the two architectures, how they’ve changed and the evolution of data center switching.

Traditional Three-Tier Architecture

three-tier architecture

Traditional three-tier data center switching design historically consisted of core Layer 3 switches, aggregation Layer 3 switches (sometimes called distribution Layer 3 switches) and access switches. Spanning Tree Protocol was used between the aggregation layer and the access layer to build a loop-free topology for the Layer 2 part of the network. Spanning Tree Protocol had a lot of benefits including a relatively easy implementation, requiring little configuration, and being simple to understand. Spanning Tree Protocol cannot use parallel forwarding paths however, it always blocks redundant paths in a VLAN. This impacted the ability to have a highly available active-active network, reduced the number of ports that were usable, and had high equipment costs.

The Fall of Spanning Tree Protoco

From this architecture, as virtualization started to grow, other protocols started to take the lead to allow for better utilization of equipment. Virtual-port-channel (vPC) technology eliminated Spanning Tree blocked ports, providing an active-active uplink from the access switches to the aggregation Layer 3 switches, and made use of the full available bandwidth. The architecture also started to change from the hardware standpoint by extending the Layer 2 segments across all of the pods. With this, the data center administrator can create a central, more flexible resource pool that can be allocated based on demand and needs. Some of the weaknesses of three-tier architecture began to show as virtualization continued to take over the industry and virtual machines needed to move freely between their hosts. This traffic requires efficiency with low and predictable latency. However, vPC can only provide two parallel uplinks which leads to bandwidth being the bottleneck of this design.

The Rise of Leaf-Spine Topology

Spine-and-Leaf-Topology-Data-Center-Switching

Leaf-spine topology was created to overcome the bandwidth limitations of three-tier architecture. In this configuration, every lower-tier switch (leaf layer) is connected to each of the top-tier switches (spine layer) in a full-mesh topology. The leaf layer consists of access switches that connect to servers and other devices. The spine layer is the backbone of the network and is responsible for interconnecting all leaf switches. Every leaf switch is connected to every spine. There can be path optimization so traffic load is evenly distributed among the spine. If one spine switch were to completely fail, it would only slightly degrade performance throughout the data center. Every server is only a maximum number of hops from any other server in the mesh, greatly reducing latency and allowing for a smooth vMotion experience.

Leaf-spine topology can also be easily expanded. If you run into capacity limitations, expanding the network is as easy as adding an additional spine switch. Uplinks can be extended to every leaf switch, resulting in the addition of interlayer bandwidth and reduction of oversubscription. If device port capacity becomes a concern, a new leaf switch can be added. This architecture can also support using both chassis switches and fixed-port switches to accommodate connectivity types and budgets. One flaw of the spine-and-leaf architecture, however, is the number of ports needed to support each leaf. When adding a new spine, each leaf must have redundant paths connected to the new spine. For this reason, the number of ports needed can grow incredibly quickly and reduces the number of ports available for other purposes.

Conclusion

Now, we are witnessing a change from the traditional three-tier architecture to a spine-and-leaf topology. With the increasing demand in your data center and east-west traffic, the traditional network topology can hardly satisfy the data and storage requirements. And the increasingly virtual data center environments require new data center-class switches to accommodate higher throughput and increased port density. So you may need to purchase a data center-class switch for your organization. Even if you don’t need a data center-class switch right now, consider it next year. Eventually, server, storage, application and user demands will require one. The best-value and cost-efficient data center switch for your choice at FS.com.

Backbone Cabling vs Horizontal Cabling

Computer networks require complicated and specific cabling, particularly in business or academic settings. The cables used in cabling the networks must be made from certain materials. Backbone cabling and horizontal cabling are two main cabling methods used in today’s structured cabling system and neither is dispensable. In order to meet different connection needs, cables used in backbone cabling and horizontal cabling also have many differences from each other. So what’s the difference between them?Knowledge of backbone cabling and horizontal cabling will be introduced in this article.

Structured Cabling System Basics
To understand backbone cabling and horizontal cabling, let’s understand the six subsystems of structured cabling firstly. These six subsystems are often found throughout a building and are connected together so that various types of data can be transmitted consistently and securely (shown in the figure below).

Structured Cabling System

  • Entrance Facility: This room is where both public and private network service cables communicate with the outside world.
  • Equipment Room:  A room with equipment that serves the users inside the building.
  • Telecommunications Room: This room contains the telecommunications equipment that connects the backbone and horizontal cabling subsystems.
  • Backbone Cabling: A system of cabling that connects the entrance facilities, equipment rooms and telecommunications rooms.
  • Horizontal Cabling: The system of cabling that connects telecommunications rooms to individual outlets or work areas on the floor.
  • Work Area Components: These connect end-user equipment to outlets of the horizontal cabling system.

 

Backbone Cabling
The backbone cabling is also called vertical cabling or wiring. It provides interconnection between telecommunication rooms, equipment rooms and entrance facilities. These backbone cablings typically are done from floor to floor to floor. When setting up backbone cabling, several types of media can be used: unshielded twisted-pair (UTP) cable, shielded twisted-pair (STP) cable, fiber optic cable, or coaxial cable. Equipment should be connected by cables of no more than 30 meters (98 feet).

Backbone Cabling

With the emerge of Gigabit Ethernet and 10 Gigabit Ethernet, fiber optic cable is the most appropriate choice for backbone cabling since they provide much higher bandwidth than traditional Cat5, Cat6 or even Cat7 twisted pair copper cables. Another advantage of fiber is that fibers can run much longer distance than copper cable, which makes them especially attractive for backbone cabling.

Horizontal Cabling
The horizontal cabling system extends from the work area’s telecommunications information outlet to the telecommunications room (TR) or telecommunications enclosure (TE). As shown in the figure below, horizontal cabling is usually installed in a star topology that connects each work area to the telecommunications room. It includes the telecommunications outlet, an optional consolidation point, horizontal cable, mechanical terminations and patch cords (or jumpers) located in the TR or TE.

Horizontal Cabling

Four-pair 100-ohm unshielded twisted-pair (UTP) cabling (Cat5 or Cat5e cabling) is usually recommended for new installations because it supports both voice and high-speed data transmission. To comply with EIA/TIA wiring standards, individual cables should be limited to 90 meters in length between the outlet in the work area and the patch panels in the telecommunications room. Patch cords for connecting the patch panel to hubs and switches in the telecommunications room should be no longer than 6 meters total distance. Cables connecting users’ computers to outlets should be limited to 3 meters in length.

Backbone Cabling  vs Horizontal Cabling
Although the same types of cables are used for both backbone and horizontal cabling, since backbone cabling typically passes through from floor to floor, the cables used for backbone cabling have very different requirement from the horizontal cablings. Backbone cables must meet particular fire-rating specifications, typically OFNR (Optical Fiber Non-Conductive Riser) rated. If the backbone cable passes through plenum area (spaces in the building used for air return in air conditioning), the cable must be OFNP (Optical Fiber Non-conductive Plenum) rated. Besides, since backbone cables need to have enough strength to support its own weight, cable strength for backbone cables is also different from horizontal cables. And unlike horizontal cables, backbone cables must be secured correctly.

Conclusion
As two important parts of structured cabling, both backbone cabling and horizontal cabling play an irreplaceable role. And due to the different cabling environment, backbone cables and horizontal cables may have different specifications. FS.COM provides both Cat5, Cat6 or Cat7 UTP or STP copper cables and OFNR or OFNP multimode or single-mode fiber patch cables for backbone cabling and horizontal cabling. For more information about the backbone cabling and horizontal cabling solutions or other cabling solutions, please contact us via sales@fs.com.

Source:http://www.fs.com/blog/

Cabling Solution for Upgrading to 40G and 100G Fiber

Migrating from 10G (that uses two fibers in either a SC Duplex or a LC Duplex connector) to 40G and 100G fiber will require a lot more fibers and a different type of connector. The way that optical fiber cabling is deployed for 10G can facilitate an easier migration path to 40G and 100G fiber in the future. An effective migration strategy needs to provide a smooth transition to the higher Ethernet speeds with minimum disruption and without wholesale replacement of existing cabling and connectivity components.

10G use LC duplex cabling

Optical fiber cabling is commonly deployed for backbone cabling in data centers for switch to switch connections and also for horizontal cabling for switch to server and storage area network connections. The use of pre-terminated optical fiber cabling can facilitate the migration path to 40G and 100G fiber in the future. Figure below illustrates a pre-terminated cable assembly (MPO cassette) containing 24 OS2 single-mode fibers with two 12-fiber MPO connectors at both ends. This fiber cable assembly plugs into the back of a breakout cassette that splits the 24 fibers into 12 LC Duplex connectors at the front of the cassette.

MPO cassette has duplex lc connector and MTP connector

Four of these cassettes are mounted in a one rack unit (1U) patch panel to provide up to forty-eight 10G equipment connections using LC Duplex patch cords. The FS.COM FHD 1U fiber enclosure with four LC Duplex cassettes is illustrated in Figure below.

1U fiber enclosure with four LC Duplex cassettes

If upgrading from 10G to 40G, one or more of the LC duplex cassette(s) can be replaced with 12 port MPO adapters. The MPO adapters are designed to fit in the same opening as the cassettes. The Figure below illustrates the case where all four cassettes are replaced with four high density 12 port MPO adapters. This solution illustrates an upgrade path from 10G to 40G that does not require any additional space and reuses the same patch panels. The 12 LC duplex cassette(s) are replaced with 12 port MPO adapter(s) as needed. Additional 24-fiber cable assemblies (or any fiber counts in multiples of 12 fibers) are provided as needed for backbone or horizontal cabling.

1U fiber enclosure with four MPO adapter

What Are the Advantages and Disadvantages of Optical Fiber Cable?

An optical fiber or fiber optic cable is a flexible, transparent fiber made by drawing glass, which are used most often as a means to transmit light between the two ends of the fiber and find wide usage in fiber-optic communications, where they permit transmission over longer distances and at higher bandwidths (data rates) than wire cables. Whether should I use optical fiber cables in my network? What are the advantages and disadvantages of optical fiber?

Fibre-Optic-Cable

Advantages of Optical Fiber Cable

  • Bandwidth

Fiber optic cables have a much greater bandwidth than metal cables. The amount of information that can be transmitted per unit time of fiber over other transmission media is its most significant advantage.

  • Low Power Loss

An optical fiber offers low power loss, which allows for longer transmission distances. In comparison to copper, in a network, the longest recommended copper distance is 100m while with fiber, it is 2km.

  • Interference

Fiber optic cables are immune to electromagnetic interference. It can also be run in electrically noisy environments without concern as electrical noise will not affect fiber.

  • Size

In comparison to copper, a fiber optic cable has nearly 4.5 times as much capacity as the wire cable has and a cross sectional area that is 30 times less.

  • Weight

Fiber optic cables are much thinner and lighter than metal wires. They also occupy less space with cables of the same information capacity.  Lighter weight makes fiber easier to install.

  • Security

Optical fibers are difficult to tap. As they do not radiate electromagnetic energy, emissions cannot be intercepted. As physically tapping the fiber takes great skill to do undetected, fiber is the most secure medium available for carrying sensitive data.

  • Flexibility

An optical fiber has greater tensile strength than copper or steel fibers of the same diameter. It is flexible, bends easily and resists most corrosive elements that attack copper cable.

  • Cost

The raw materials for glass are plentiful, unlike copper. This means glass can be made more cheaply than copper.

Disadvantages of Optical Fiber Cable

  • Difficult to Splice

The optical fibers are difficult to splice, and there are loss of the light in the fiber due to scattering. They have limited physical arc of cables. If you bend them too much, they will break.

  • Expensive to Install

The optical fibers are more expensive to install, and they have to be installed by the specialists. They are not as robust as the wires. Special test equipment is often required to the optical fiber.

  • Highly Susceptible

The fiber optic cable is a small and compact cable, and it is highly susceptible to becoming cut or damaged during installation or construction activities. The fiber optic cables can provide tremendous data transmission capabilities. So, when the fiber optic cabling is chosen as the transmission medium, it is necessary to address restoration, backup and survivability.

  • Can’t Be Curved

The transmission on the optical fiber requires repeating at distance intervals. The fibers can be broken or have transmission losses when wrapped around curves of only a few centimeters radius.

Conclusion
Fiber optic cable has both advantages and disadvantages. However, in the long run, optical fiber will replace copper. In today’s network, fiber optic cable becomes more popular than before and is widely used. FS.COM, as a leading optics supplier, provides all kinds of optical fiber cables with high quality and low price for your option.

Difference Between Straight Through and Crossover Cable

Ethernet cables can be wired as straight through or crossover. The straight through is the most common type and is used to connect computers to hubs or switches. They are most likely what you will find when you go to your local computer store and buy a patch cable. Crossover cables are more commonly used to connect a computer to a computer and may be a little harder to find since they aren’t used nearly as much as straight through cable. Then, what’s the difference between them? Difference between straight through and crossover cables will be introduced in this blog.

T568A And T568B Wiring Standard Basis
A RJ45 connector is a modular 8 position, 8 pin connector used for terminating Cat5e or Cat6 twisted pair cable. A pinout is a specific arrangement of wires that dictate how the connector is terminated. There are two standards recognized by ANSI, TIA and EIA for wiring Ethernet cables. The first is the T568A wiring standard and the second is T568B. T568B has surpassed 568A and is seen as the default wiring scheme for twisted pair structured cabling. If you are unsure of which to use, choose 568B.

t568a-t568b-wiring-standard

What Is Straight Through Cable?
A straight through cable is a type of twisted pair cable that is used in local area networks to connect a computer to a network hub such as a router. This type of cable is also sometimes called a patch cable and is an alternative to wireless connections where one or more computers access a router through a wireless signal. On a straight through cable, the wired pins match. Straight through cable use one wiring standard: both ends use T568A wiring standard or both ends use T568B wiring standard. The following figure shows a straight through cable of which both ends are wired as the T568B standard.

straight-through-cable

What Is Crossover Cable?
An Ethernet crossover cable is a type of Ethernet cable used to connect computing devices together directly. Unlike straight through cable, crossover cables use two different wiring standards: one end uses the T568A wiring standard, and the other end uses the T568B wiring standard. The internal wiring of Ethernet crossover cables reverses the transmit and receive signals. It is most often used to connect two devices of the same type: e.g. two computers (via network interface controller) or two switches to each other.

Crossover Cable

Choose a Straight Through or Crossover Cable?
Usually, straight through cables are primarily used for connecting unlike devices. And crossover cables are use for connecting unlike devices alike devices.
Use straight through cable for the following cabling:

  • Switch to router
  • Switch to PC or server
  • Hub to PC or server

Use crossover cables for the following cabling:

  • Switch to switch
  • Switch to hub
  • Hub to hub
  • Router to router
  • Router Ethernet port to PC NIC
  • PC to PC

choose-straight-through-or-crossover-cable

Conclusion
Straight through and crossover cables are wired differently from each other. One easy way to tell what you have is to look at the order of the colored wires inside the RJ45 connector. If the order of the wires is the same on both ends, then you have a straight through cable. If not, then it’s most likely a crossover cable or was wired wrong. At present, the straight through cable is much more popular than crossover cable and is widely used by people. FS.COM provides a full range straight through Cat5e, Cat6, Cat6a and Cat7 Ethernet patch cables with many lengths and colors options. Look for Ethernet patch cables, just come to FS.COM!