Månadsvis arkiv: August 2016

Cabling Guide for Cisco Nexus 9508 Switch

Due to the the ever-expanding data center consolidation, virtualization and cloud technologies, network installers feel the urge to maintain a competitive advantage of their infrastructure. Except for the performance, bandwidth and latency in datacenter cabling, management and operational agility and simplicity have also elevated themselves to the top mind of data center architects and operator. Cisco Nexus 900 series represents a familiar starting point on the journey toward a new era in software-defined network, which is announced to be the most port dense and power efficient plus fastest packet forwarder and programmable data center modular switch in the industry. This article introduces basic information of Cisco Nexus 9000 series and the cabling solutions for Nexus 9508 switch.

Cisco Nexus 9000 Series Switch

According to Cisco’s announcement, the Nexus 9000 Series switch is the foundation of the Cisco next generation data center solution. The Cisco Nexus 9000 Series switch contains two main branches including the Nexus 9300 series fixed switches and Nexus 9500 series modular switches. Of particular interest is the Nexus 9508 of 9500 series, which is impressive in terms of performance, power efficiency, 10/40GbE and future 100GbE port density, programming environment and orchestration attributes. The following image shows the inner structure of the Cisco Nexus 9508 switch.

inner sructure of Cisco 9500 switch

Cisco Nexus 9508 can offer up to 8 line cards slots with a comprehensive selection of modular line cards in a 13RU space. There are totally three line card options available: 48 port 1/10GbE SFP+ with four 40GbE QSFP+, 48 port 1/10GBASE-T with four 40GbE QSFP+ and 36 port 40GbE QSFP+ full line rate. The 1/10GbE line cards provide 640 Gbps of line rate capacity. And the 40GbE line card is based on QSFP+ form factor. From a network design perspective, the Cisco Nexus 9508 switch can be configurable with up to 1152 10 Gigabit Ethernet or 288 40 Gigabit Ethernet ports, which is very helpful for 10GbE & 40GbE migration.

Main Features of Cisco Nexus 9508 Switch

The Cisco Nexus 9508 is a versatile data center switching platform that can host 10, 40, and future 100 Gigabit Ethernet interfaces. Other than this, the switch also has other unique features:

Predictable high performance—The switch delivers 30 Tbps of non-blocking performance with latency of less than 5 microseconds, enabling data center customers to build a robust network fabric that can scale from as few as 200 10 Gigabit Ethernet server ports to more than 200,000 10 Gigabit Ethernet server ports.

Nonblocking, high-density 1 to 10 & 10 to 40 Gigabit Ethernet transition—The Cisco Nexus 9500 platform helps organizations transition from existing 1 Gigabit Ethernet Cisco Catalyst®6500 series switches server access designs to 10 Gigabit Ethernet server access designs with the same port density. And it can also helps organizations transition from 1 and 10 Gigabit Ethernet infrastructure to 10 and 40 Gigabit Ethernet infrastructure to support the increased bandwidth demands.

Advanced optics—This switch can directly use the pluggable 40 Gigabit Ethernet QSFP+ bidirectional transceiver that enables customers to use existing 10 Gigabit Ethernet data center cabling to support 40 Gigabit Ethernet connectivity.

Highly available, scalable, and robust solution—All major components are redundant, including supervisors, system controllers, power supplies, and fan trays. The switch line cards use a mix of merchant and Cisco application-specific integrated circuits (ASICs) to produce a low-complexity, low-cost design. All buffer memory is integrated into the forwarding ASICs, avoiding the need for a large number of external memory modules.

All transceivers are pluggable to support the highest possible mean time between failure (MTBF) for the switch. What’s more, the flexible and efficient chassis design has 100% headroom for future expansion with the capability to support more bandwidth and cooling and twice the number of power supplies needed to support today’s maximum configuration.

Power efficiency—The Cisco Nexus 9500 platform is the first switch chassis designed without a midplane. Line cards and fabric modules connect directly. This design approach provides optimal front-to-back airflow and helps the switch operate using less power. In addition, all Cisco Nexus 9000 series power supplies are 80 Plus Platinum rated. The typical power consumption per 10 Gigabit Ethernet port is less than 3.5 watts (W). The typical power consumption of each 40 Gigabit Ethernet port is less than 14W.

QSFP+ Direct Attach Copper Cabling

As we all know, direct attach cables (DACs) are often used to connect two or more switches which are in the same rack or in the adjacent rack. This is done to reduce the cabling cost for which DACs are much cheaper than transceivers and fiber patch cords. The following figure shows a wiring option for a Cisco Nexus 9396 to Cisco Nexus 93128 using 40G QSFP+ to 40G QSFP+ DAC cabling assemblies.

QSFP+ DAC cables

40G QSFP+ to 4 x 10 SFP+ Interconnection

The Cisco Nexus 9508 switch can also be operated in 4×10 Gigabit Ethernet mode. If the interface is logically configured as a 4×10 Gigabit Ethernet port, then each port becomes four 10Gbqs port. This will be accomplished by using copper twinax, hydras or breakout cables. This scenario can be achieved by connecting a Cisco Nexus 9000 Series Switch to a Cisco Nexus 2232 using a QSFP+ to four SFP+ copper hydra cable assembly.

QSFP+ to 4SFP+

40GE QSFP SR4/CSR4 Optics Cabling Options

Multimode fiber cabling is generally preferred when the distance between Cisco Nexus 9508 switch and other switches is less than 400 meters. In this circumstance, 40G QSFP+ SR4/CSR4 transceivers and MPO interconnect cable assemblies are often used. The following scenario shows how the Cisco Nexus 9508 switch is connected to Cisco Nexus 93128 switches with 40G QSFP+ SR4/CSR4 optics and MPO cable assemblies.


40GbE Connectivity With 40G BiDi Optics

As noted before, Cisco 40G SR-BiDi QSFP can be used in Cisco Nexus 9508 switch for 40G connectivity. The 40G BiDi QSFP multiplexes two 10GbE signals into one 20GbE stream and runs two 20GbE wavelengths on the optics side, and delivers a QSFP pluggable MSA compliant electric signal to the switch module, thereby only requiring the termination of a dual LC connector as used in 10GbE optical infrastructure. The SR-BiDi QSFP enables the re-use of existing 10GbE multimode fiber cable infrastructure plus patch cables as it supports the same LC connector. The SR-BiDi QSFP eliminates the cable infrastructure upgrade requirement of today’s 40GbE, which can lower capex of cabling and switch hardware. The following image shows the Cisco Nexus 9508 switch using 40G BiDi transceiver providing a zero-cost fiber cabling upgrade path for 10GbE to 40GbE.



Cisco is offering a practical way to transition to higher speed data center networking through favorable economics. With the use of Cisco Nexus 9508 switch, designers will embrace a new programmable network platform ready for the age of software-defined networking. FS.COM provides various 40G QSFP+ transceivers and fiber optic cable for the 40G connection of Cisco Nexus 9508 switch. 10G SFP+ transceivers and MPO/MTP-LC harness fiber patch cables for the 10G SFP+ to 40G QSFP+ direct connection are also provided. Please kindly contact us for more information.

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Is It Worthwhile to Use Cat 7 Ethernet Cable?

Ethernet cables provide stable internet connection between electrical devices, which are standardized cables to facilitate easy communication between disparate electronic equipment. These electronic devices can either be fax machines, printers, scanners, or personal computers. Ethernet cables can be categorized into several types based on different specifications. Category 7 Ethernet cable, also refers to Cat 7, which is the wire used for cabling infrastructure of Gigabit Ethernet. it is known that Cat7 is the more expensive option compared to Cat 5e and Cat 6 cables. Users might be wondering whether it is worth the extra money to consider Cat 7 cables. The answer to this solution will be clearly introduced in this passage.


Quick Review of Cat 7 Cables

The Cat 7 cable refers to the transmission cord standard cable used in the 10G Ethernet and other Cat 5/Cat 6 downhill compatible networks. The Cat 7 cable is an 8-core safeguarded cable that each pair of cable has a shield. The program of Cat 7 cables is incompatible with RJ45. A Cat 7 cables can offer performance of up to 600MHz, which is 6 times as fast as cat 5e and 2. 4 times as fast as cat 6. Besides this, Cat 7 cable, whilst being the more expensive option, is also considered the most durable, and has a longer lifespan than Cat 5 and Cat 6, improving its overall return on investment, and is the best choice for wiring with the future in mind.

Comparing Cat 7 Ethernet Cable With Cat 5/Cat 6 Cables

The mostly used Ethernet cables are not a brand name or generic, they are separated into different standard categories like Cat 5, Cat 5e, Cat 6 and Cat 7. Each one of them is backward compatible, meaning that you can plug a newer cable into a device created for a slower cable, and you will not have any compatibility problems. For companies that are still using the older Ethernet cables, maybe it is time for them to upgrade to a newer version. Cat 7 as the newly released category, opposes the better performance than the former Category Ethernet cables. The following chart shows the distinctions in different Ethernet Categories.


Cat 7 cables requires its twisted wires to be fully shielded known as Screen Shielded Twisted Pair (SSTP) or Screened Foiled Twisted Pair (SFTP) wiring, which completely eliminates alien crosstalk while significantly improving noise resistance. Thus it allows the user to get higher possible speeds even with longer cables. When compared at lengths of 100 meters of cable, the following numbers show the difference in Ethernet cable categories:

Cat 5 Ethernet cable is typically too slow for business networks, allowing the user to transmit up to 100 Mb/second speed at 100 Mhz. Cat 5e Ethernet cable allows up to 1 Gb/s internet speed with 100 Mhz. Cat 6 Ethernet cable allows up to 1 Gb/s, but cable lengths up to 55 meters can get internet speeds of 10 Gb/s at 250 Mhz. Cat 7 Ethernet cable is the newest cable category, operating at speeds of 10 Gb/s at 100 meters of cable and transmitting frequencies up to 600 Mhz.

Why Implementing Cat 7 Cable?

As noted before, Cat 7 cable is able to achieve higher transmission speed and longer distances than the preceding Ethernet cables like Cat 5, Cat 5e, and Cat 6 cables. What’s more, Cat 7 has an overall shield as well as individual shielding of every pair. Therefore it is much more resilient to interference compared to a CAT 5 cable. The following picture shows a SSTP Cat 7 cable.


To better meet the future demand, Cat 7 cables is an dispensable solution as it can create an expandable and flexible cabling system which will save you the expense of re-wiring for new features in the future! One point that we shouldn’t miss out is that Cat 7 cable has a copper cross-section than the Cat 5, which means the individual cores in Cat 7 are easier to work with. Then opt for Cat 7 cables will benefit you a lot.

Solid or Stranded Ethernet Cables

This refers to different methods the wires used within the cable. The solid cable uses one single piece of copper for an electrical conductor. The stranded cable uses multiple (and thinner) copper cables twisted together for the electrical conductor. This makes the stranded cable more flexible, perfect for navigating a complex space. The solid cable is far less flexible making it ideal for permanent installation in the walls or outdoor. This wiring method is not suitable for fiber optic cables like ST-LC patch cord.

Our Recommendations

In summary, careful planning and product selection will be the key to a successful installation. Resolution, distance, signal types, environment, and physical layout are the important factors that you should consider when choosing a transmission media. Cat 7 cable can support 10 Gigabit Ethernet with plenty of margin to spare, and it has pair-sharing capability, making it possible to use one cable to power several different devices at the same time utilizing each pair as needed. FS.COM offers the best and most versatile copper cables including Cat 5e, Cat 6 and Cat 7 products. Fiber optic cables are provided as well. Fiber patch cables LC to LC, LC LC single mode fiber patch cable, and SC to LC patch cable are all offered at minimum price. If you have any interest, please send your request to us.

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Seven Tips for the Cable Installation

Cable installation can be a finicky thing. People without appropriate knowledge and training can not be capable of running cables, otherwise they will end up with network failure. End users might have the experience of running telephone cables, so that they want to take the risk of wiring network cables. In fact, telephone cables can tolerate quite a lot of errors, but that is not the case of the data cabling as it is quite sensitive to cable errors. Therefore, to avoid potential network error and reduce your risks of costly mistakes, here are several things you should know before the cable installation.

Using Cable Management

The first thing you should bear in your mind is that the cabling work won’t stop with the initial installation. More cables and optical devices will be added. Thus to make sure that you label appropriate cables, color-code cables, or implement some other kind of process to make it easier to identify cables later on. What’s more, adding ladder rack, rack-based cable management makes ongoing maintenance much, much easier. The following image can easily illustrate the importance of fiber cable management.

beforeafter cable mangaement

Running Cable in Parallel With Electrical Cables

Data cabling used UTP (unshielded twisted pairs) to achieve its goals. The magnetic field generated by the low voltage running through the cable is a critical component of the communications chain. When you run this unshielded cabling in parallel with electrical cables, that magnetic field is disrupted and the communication becomes noisy and garbled. In many cases, transmissions will simply not make it from Point A to Point B. In other cases, transmission rates will slow to a crawl as communications are constantly retried. If you have to go near electrical power lines, cross them in perpendicular instead. From a personal experience, a newly installed coaxial cable can be easily out of work if they are twisted around the overhead electrical cabling that ran between the two buildings.

Minding Distance Limitations of Your Cabling

It is known that the typical distance limitations for UTP cabling with up to 1 Gbps is 100 meters. However, if you’re running cabling for some other purposes, such as 10 Gbps or 40 Gbps, be mindful of the distance limitations associated with the type of cabling you intend to use. For example, if you intend to run 10 Gbps for up to 100 meters over twisted pair cabling, you need to use Category 6A or better cabling. Or if you are running 10 Gbqs for up to 10 km, you need to use 10GBASE-LR SFP+with patch cord LC-LC.

Planning for Future Proofing

Maybe your network only provision 100 Mbps network connections to the desktop for now, even though the 1G Ethernet has become a ubiquitous standard. But suppose you are going to move to a new location and you need to install new cabling. Are you going to go with yesterday’s best cabling technology or are you going to install something that will meet today’s needs and your needs for the next few years?

Remember, the labor is the most expensive part of your project. While top-of-the-line cable won’t be the least expensive option, you should consider reasonably high-end cable for your installation. Maybe you don’t go with the absolute best, after all, many organizations won’t need 10 Gbps to the desktop for quite some time but don’t go for cheap, either.

Following the Cabling Standards

Many users might have the fallacy that there are only eight individual wires inside a cabling jacket, so why not terminate them at random as long as you use the same scheme at both ends? Of course, that is the bad ideas.

wiring standard

The cabling standard known as EAI/TIA-568-A and B are existed for a reason. This standard defines how the cables are twisted and placed in the jacket. If you deviate from those standards, you risk introducing noise and inefficiency into your cable plant that can have a negative impact on overall network performance. The following image shows UTP Cable Termination Standards EIA/TIA 568A and EIA/TIA 568B, and the only difference is that the green and orange pairs are terminated to different pins.

Testing the Cabling Results to Ensure Cabling System Properly Functioned

Once the cabling is installed, you should test every cable using appropriate tools to make sure that it will be suitable for its intended use. Fiber optic testing of newly installed systems not only verifies that the system meets its design requirements, but also creates a performance baseline for all future testing and troubleshooting of that system to support the evaluation of warranty claims. The following image shows a Visual fault locator (VFL), designed with a visible laser and universal adapter like FC, SC and ST etc., which can help user easily locate faults on the fiber link.

vfl cable tester

This testing typically includes verifying length and cable specifications matched to needs. If you need 1 Gbps transmission speeds, verify that the cable’s properties will support that need. This testing result will ensure that the data necessary to properly evaluate any future system malfunctions will be available.

Ensure a Quality Installation With Quality Fiber Optics

The amount of information carried in two strands of optical fiber would require a copper cable four inches in diameter. When considering the space constraints, required bandwidth, and long distance transmission needs in today’s applications, fiber optic products are the only viable choice. Easy installation and upgrades allow you to meet future growth needs and install spare fiber today for a more economical choice than installing additional cables later. FS.COM gives you quality products for all your fiber optic needs to reduce your risk of network failure.


To sum up, improperly installed cabling can cripple network performance, create maintenance headaches, and lead to hidden costs. Besides the above tips, you are supposed to increase error-free work with trained technicians. Because the best practice in cable installation is a professional with the proper tools and certifications to ensure the proper installation of the network cabling. Note that a beginner who has little experience in cable installation should be instructed under a professional technician to proceed the cable installation.

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Using A GLC-SX-MM Transceiver To Connect Gigabit Ethernet Network

If you are still using a 100BASE network, or GBIC transceiver for a small office, you may run into the limitations of last decade’s technology. Because the 100BASE standard network is just fine for a small office, but it isn’t sufficient to handle heavier network use. As your network expands, you might experience problems like: dropouts in your VoIP calls, Sluggish data retrieval speeds, or poor video streaming quality. If you have encountered any of this, maybe it’s time to start thinking about an upgrade to gigabit Ethernet, which moves at ten times the speed of traditional Ethernet. This article will explain the Gigabit Ethernet in the following aspects: the compatible SFP transceiver, the difference between twisted copper and fiber optic Ethernet.

Compatible SFP Transceiver

When contemplating an upgrade to gigabit Ethernet, there are a number of issues involved in the network transition. But one of the most immediate concerns people have is how much new hardware they’ll have to purchase. The good news is that one of the basic issues providing connectivity is generally quite easy.

Cisco SFP

The representative of the optical transceivers for Gigabit Ethernet is Small Form-factor Pluggable (SFP). These Small Form-factor Pluggable slots allow transceivers like the GLC-SX-MM to be plugged in and provide instant gigabit Ethernet connectivity. In the last few years, when you purchased your networking equipment, it should have some industry-standard SFP ports, based on a Cisco standard. And you can only purchase the original expensive SFPs. However, the monopolized SFP market is unhealthy for the development of optical technology, nowadays people can appreciate the low price and high performance of compatible SFP transceivers from OEM vendors.

How to Ensure the Compatibility of the SFP Transceiver

Although the OEM or alternative party compatible SFP transceivers are much cheaper than the original ones, people are hesitated to use them. In fact, there are mainly two factors that will have an impact on the compatibility of the SFP transceivers. First, does the SFP optics require DDM function? Second, does the host equipment check the ID code and lock out alternative party components?

Certainly from our experience, most Cisco core equipment and routers do lock out all but Cisco ID SFP modules. We do not have an extensive report on what Cisco equipment does and does not lock out third party SFP.

The only way to know for sure is to try an authorized component if the host equipment rejects it. Remember, the compatibility has nothing to do with the functions of the transceiver, only in recognizing ID code and selecting to lock out third party SFP or not.

Fiber Optic Cabling Over Copper-wire Cabling

Choose to use copper-wire cabling or upgrade to fiber optic cabling in your offices is another consideration when installing a network. There is no doubt that fiber optics provide several advantages over copper, but it is more expensive than copper cabling. In addition, fiber optic supports far longer cable lengths than twisted copper.

Copper can only run for around 100 meters, whereas fiber can go between 200 and 500 feet, or more, without signal loss. Fiber has gives off no radio interference, allowing it to coexist more easily in an office with a lot of wireless devices. Because of the lack of interference, fiber is also harder to hack into than copper.

For equivalent data rates, optical cable is thinner and lighter than copper wire, and it does not need to be shielded. For these reasons, an optical cable is often lighter in weight and less bulky, and has a smaller bend radius, than the equivalent copper cable, especially with longer cables. These advantages of fiber provide more data center configuration flexibility.

cable thickness

Just as with copper, a standard GLC-SX-MM transceiver links fiber optic Ethernet with your existing equipment. Or the GLC-SX-MM-RGD transceiver is also just great for your network, which is the 1000BASE-SX SFP GLC-SX-MM transceiver with DOM support.

For future proofing, moving away from copper is probably a good idea. Fiber optics are growing steadily in popularity among businesses which have taken over large office buildings, created expansive complexes, or need to collaborate with remote offices in real time.

Additional Information

The biggest advantage of Cisco’s SFP system is that it’s entirely hot-swappable. It doesn’t matter what the device is, from servers to your switch to simple Ethernet cards: If it has an SFP port on it, it can support a multitude of transceivers for different functions, through one standardized interface. In fact, that standardization means that third parties can produce transceivers which are as good as official Cisco units. So, if you decide that fiber optic gigabit Ethernet is what you need for your future business communications needs, the GLC-SX-MM transceiver is truly simple to install and use.


End-users are wondering about whether they should upgrade to higher-bandwidth network as the existing network like 100BASE standard is fine for their network. However, the transition to higher internet speed is going to happen sooner or later. There are several different gigabit Ethernet standards out there, so keep in mind to see which best fits your vision for the future of your business. Note that you’ll need transceivers like the GLC-SX-MM to connect your existing devices to the new network.

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40G QSFP+: Data Center Bandwidth Provider

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In-depth Understanding of LC Duplex Connectors

As one of the small form factor (SFF) field polish connectors, LC duplex connectors are widely used for equipment cross-connects or interconnects in backbone, horizontal and work area applications for high-speed data transmissions. They provide a solution for high-density telecommunication rooms, LANs (Local Area Networks), public networks and fiber-to-the-desk applications. While talking about LC duplex, most just think them as the small useful tools which allow fast and easy field termination for fiber optic connectivity. Actually, LC duplex connectors are more than what their design and appearance show. Their world are full of colors. This article guides the inner world of these LC duplex connectors from their several family members.

Standard LC Duplex

It’s known that the standard LC connector is developed by Lucent Technologies. Its connector body is squarish shape that is similar to SC connector, and has half the size of the SC. Standard LC duplex connectors are LC with a duplex configuration with a plastic clip. The fibers used to terminate in its 1.25mm ceramic ferrule can be both single-mode and multi-mode versions, such as LC to LC fiber patch cable single mode and LC LC multimode patch cord. Compared with SC, LC’s high-density design and 1.25mm ferrule double the port density, reducing space requirements on racks, enclosures, panels and faceplates. Nowadays, LC duplex connectors are still popular both in telcos and high bit rate LANs, etc..

LC to LC fiber patch cable single mode

Mini-LC Duplex

As a variation of standard LC duplex, the mini-LC duplex uses current industry-standard LC connectors, but allows closer ferrule spacing by using the duplex clip (usually with color coding)—mini-LC has a reduced center spacing of 5.25mm compared to a standard LC of 6.25 mm. This type of LC duplex connector is designed to operate with the Mini SFP modules and provide a higher density deployment for data center equipment.

Mini-LC Duplex vs. Standard LC Duplex

LC Duplex with Uniboot

LC duplex connector with uniboot is two LC connectors encased in a common housing with one boot, terminated on a single twin-fiber round cable. This type of connector is more compact compared to standard LC duplex. Fiber patch cables terminated with uniboot LC duplex connectors, are ideal for high-density cabling application since they reduce more fiber counts and greatly reduce cable management space. (The boots of an LC duplex connector can be configured with various versions according to different requirements. In addition to standard connector boots and uniboots, there are mini boots, BTW (Behind the Wall) boots, short boots, and 45 or 90 degree angel boots in the market.)

LC Duplex with Uniboot

LC-HD Duplex

In practical operation, it’s not easy to release the LC duplex connectors in patch panels, and sometimes thumbs and forefingers are not ideally suited to operate the release lever and pulling the connector. As such, LC-HD duplex connectors are designed to help deal with this issue. With a flexible “pull-tab” or “push-pull tab”, the LC-HD duplex connector can be disengaged easily from densely loaded panels without using the special tools which allows users easy accessibility in tight areas when deploying in data center high-density applications. Some types of LC-HD duplex connectors combine the advantages of uniboot, which make them more suitable to high-density cabling applications.


Keyed LC Duplex

Keyed LC duplex connectors are available in 12 colors, thus creating a colorful LC world. Each color of the keyed LC duplex connectors represents a unique keying pattern which only allows its matched color-coded adapter mating. This kind of LC duplex connector can help segregate or identify of parts or paths within a network infrastructure, as well as reducing the risk of accidental or malicious network access, particularly in shared access areas or in secure hierarchical environments.

Keyed LC duplex connectors

LC Duplex Connector Advantages

The LC duplex connector is designed in response to the growing needs for smaller and easier-to-use fiber optic connectivity. It simplifies moves, adds, and changes, and reduces installation time for field mountable connectors, time- and money-saving. Additionally, it doubles fiber density in shelves and outlets –lowering system costs again, as well as improves durability and reduces cross-connect rearrangement effort.


LC duplex connector uses an improved version of the familiar and user-friendly telephone plug, which provides a reassuring, audible click when engaged. The unique combination of small size and the click of connectivity makes the LC duplex the right choice for your network. With the increasing connectivity requirements. The family LC duplex connectors are sure to be enlarged. When you want to buy these connectors, Fiberstore is a good choice for many LC solutions. Besides LC solutions, SC solutions are also available for you,like SC patch cord, SC adapters, and so on. Visit Fiberstore for more information about LC and SC fiber optic solutions.

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