Has the Linux Foundation, the most powerful nonprofit organization in the open source world, sold out to corporate interests? And how committed is it to defending the GPL free software license? Those are questions some critics are asking in the wake of recent changes to the Linux Foundation’s by-laws.

As former Red Hat (and current CoreOS) employee Matthew Garrett first noted, the Linux Foundation in mid-January modified its by-laws so that individual members of the organization can no longer participate in elections for the organization’s board of directors.

Since the other members of the organization consist of corporations, this means people who are not associated with a big company can’t help decide who gets to run the Linux Foundation.

In some ways, this change would seem relatively minor. It’s not as if the Linux Foundation is now only allowing corporations to join, or excluding non-corporate viewpoints entirely.

But Garrett speculates that the change was made to prevent Karen Sandler, executive director of the Software Freedom Conservancy and a staunch supporter of software freedom, from succeeding in her recently announced election bid for the Linux Foundation board. Sandler’s organization is currently enmeshed in a legal battle against VMware over claims that the company violated the terms of the GPL, the license that governs the open source code of Linux and many other major open source projects.

The Linux Foundation has issued relatively little public commentary on this issue. It’s still not clear whether the by-law change would prevent Sandler from running for the board, or just change the way other individual members of the Linux Foundation participate in board elections.

And it’s not even certain that the timing of the change and Sandler’s candidacy announcement was more than coincidental — although the Linux Foundation has not denied as much. The by-law change was made Jan. 15 and Sandler announced her candidacy Jan. 17.)

All the same, it seems unlikely that the Linux Foundation would risk so much face in the mere interest of providing a small, mostly symbolic help to VMware in its ongoing legal battle. The companies represented by the current board are hardly all in bed with VMware. The Foundation has much more to lose by seeming to be favoring corporations over the open source community writ large than it does by angering VMware, a company that deals mostly in closed-source software and has no singular influence over the Linux kernel.

If the by-law change was related to Sandler, I suspect the Linux Foundation’s strategy is simply to avoid setting a precedent of making it easy for activists to assume a leading role in the organization. That move would still have implications for how the Foundation balances the interests of well-funded companies with those of community organizations like the one Sandler heads. But it wouldn’t be proof that the Linux Foundation is out to get the Software Freedom Conservancy for its campaign against VMware, or that it wants to protect VMware’s interests more than those of the open source community as a whole.

Originally published at http://thevarguy.com/open-source-application-software-companies/has-linux-foundation-sold-out-vmware-probably-not

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Nowadays, data centers are witnessing a rise in the number of network connections, and it’s necessary for data centers to achieve even higher-density in both ports and cabling to accommodate the bandwidth demands. Parallel optics combining the use of cables and fiber optics serve as the medium to satisfy the growing need for transmission speed and data volume.

Multi-fiber connectors bring together 12 or 24 fibers in a single interface just as compact as a RJ45 connector. The multi-fiber push-on or also multi-path push-on (MPO) technology and especially the MTP connectors from the manufacturer US Conec have proven themselves as a practical solution for high-performance data networks in data centers. This paper mainly introduces MPO/MTP technology, and parallel optics which utilizes this multi-mode connectors in 40 Gigabit Ethernet (GbE) transmission.

Before going into the main body, a table showing the 40GbE standard, cable types and maximum allowable distances is below.

As is shown in the table, while establishing 40GbE links, parallel optical channels with multi-mode fiber (MMFs) of the categories OM3 and OM4 are used. The ports have to accommodate four or even ten times the number of connectors. This large number of connectors can no longer be covered with conventional individual connectors, which explain the reason why the 802.3ba standard incorporated the MPO multi-fiber connector for 40GBASE-SR4 and 100GBASE-SR10. It can contact 12 or 24 fibers while saving space.

IEC 61754-7 and TIA/EIA 604-5 defined MPO connector that can accommodate up to 72 fibers in the tiniest of spaces, most commonly used for 12 or 24 fibers. This MPO connector is designed for the high-density connection of MMFs, allowing easy connection and disconnection. MPO connector has two alignment pins to align the ferrule, and a clamp spring. When closed, the MT connector is extremely compact and is thus well suited for high-density fiber connection within closures or cabinets. The kind of multi-mode connector combines high-density connection with convenient disconnecting action, ideal in satisfying the need for high-density packaging in equipment. In 40G links, QSFP+ transceivers use MPO connectors as the interface for high performance. Just like, this HP JG709A 40GBASE-CSR4 QSFP+ transceiver listed on Fiberstore achieves 300m link length with MPO connector.

Category OM3 and OM4 MMF are the future-proof cabling choices for 40G links. Lasers are used for OM3 and OM4. These lasers are generally vertical-cavity surface-emitting lasers (VCSELs) which are cheaper than distributed feedback lasers. The VCSELs are able to transmit data at higher rates. According to the table shown above, OM3 has a link length of 100 meters so it supports about 85 percent of all data center channels depending on architecture and size, and OM4 fibers have a link length of 150 meters so they cover nearly 100 percent of the required reach.

As noted in the table, the 802.3ba standard defines the parallel operation of four OM3/OM4 fibers for 40GbE in 40GBASE-SR4. Two fibers have to be used per link because this arrangement is full duplex operation, i.e. Simultaneous transmission in both directions. Therefore the number of fibers increases to eight for 40GBASE-SR4. That is four of the twelve fibers remain unused and eight of the twelve fibers are used in each case in connection with 12-fiber and MPO connectors. In the parallel optical link, the signal is split, transmitted over separate fibers and then joined again. That means the individual signals have to arrive at the receiver at the same time.

MPO/MTP technology is performance- and quality-assured as a trend for decision makers in to carefully plan their fiber optics infrastructure for 40GbE transmission. Fiberstore provides not only high-quality MPOMTP connectors, but also MPO-based patch cables (eg. Push-Pull MPO cable). You can visit Fiberstore for more information about MPO connectors and MPO-based cables.

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With each passing year, the demands for higher data rates and greater bandwidth in data centers grow. An increasing number of sophisticated fiber optical products have been introduced into the telecommunication market, including fiber patch cables (single-mode fibers (SMFs) and multi-mode fibers (MMFs)), with MMFs being preferred by users. MMFs have four types, OM1, OM2, OM3 and OM4. This article mainly details the differences between OM3 and OM4, helping you clear off the confusion of these two types.

The first thing to note is that OM4 is completely backwards compatible with existing OM3 systems. The connectors and termination of OM3 and OM4 are same. Besides, both OM3 and OM4 are Laser Optimised Multi-mode Fiber (LOMMF) share the same fiber core size of 50/125. So, what are the differences between them?

OM4 differs from OM3 mainly in their attenuation and dispersion provided. Let’s first see the following table which shows the attenuation and dispersion of OM3 and OM4.

• Attenuation Analysis

OM4 cable has lower attenuation than OM3. Attenuation refers to the reduction in power of the light signal as it is transmitted (dB). It’s caused by losses in light through the passive components, such as cables, and connectors, relatively simple to explain. The maximum attenuation at 850nm permitted by OM3 is less than 3.5 dB/Km, while the OM4 is less than 3.0 dB/Km. OM4 causes fewer losses.

• Dispersion Analysis

Dispersion is the spreading of the signal in time due to the differing paths the light can take down the fiber. Two types of dispersion are available: chromatic and modal. Chromatic is the spreading of the signal in time resulting from the different speeds of light rays, while modal is the spreading of the signal in time resulting from the different propagation modes in the fiber. Here the focus is put on the modal dispersion. The modal dispersion determines the modal bandwidth that the fiber can operate, and this is what the difference between OM3 and OM4 lies in. The minimum fiber bandwidth at 850nm allowed by OM3 is 2700 megahertz*Km, by OM4 is 4700 megahertz*Km, meaning that OM4 can operate at higher bandwidth.

• Other Considerations Between OM3 and OM4

OM4 is more network reliable than OM3, providing great design flexibility. What’s more, OM4 is able to reach an additional 60% links in the core-to-distribution and in the access-to-distribution channels compared to OM3 in 40G/100G Ethernet applications. In 40G Ethernet transmission using 40G QSFP, OM4 enables 150m length reach. Like Arista QSFP-40G-SR4, this 40G QSFP, when runs over OM4, enables 150m reach with MTP/MPO connector at a data rate of 40 Gbps. The image below shows what the Arista QSFP-40G-SR4 transceiver looks like.

On the one hand, since OM3 are compatible with OM4, these two types are interchangeable when the transmission distance limitations are accessible. But on the other, the additional bandwidth and lower attenuation of OM4 make it more ideal for MMF cabling infrastructure. Whether use OM3 or OM4 for your network, it depends on the specific situations, like cost, and distance required.

After detailed discussion, you may have gained a better understanding of the OM3 and OM4 differences and you can quickly choose MMF types to meet your higher bandwidth system requirements. Fiberstore OM3 and OM4 provide solutions that allow more effective and bandwidth-providing network installations. Besides fiber patch cables, Fiberstore also offers copper cables for your networks, such as QSFP-H40G-CU5M. This Cisco QSFP-H40G-CU5M product listed on Fiberstore is 100% compatible with the equivalent Cisco direct attach copper cables. For more information about fiber patch cables and copper cables, you can visit Fiberstore for more information.

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ADTRAN says more than 60 telecom service providers across six continents have utilized G.fast broadband solutions.

BT, the telecom operator in the UK, is one of the telecoms to conduct G.fast trials. The BT trials in Huntingdon, Cambridgeshire, reaching over two thousand premises are the latest to include the ADTRAN 500G Series G.fast solutions.

G.fast broadband technology is allowing carriers to deliver up to five times the broadband speed currently offered by the most progressive UK cable providers.

The company claims that ADTRAN solutions are changing the way broadband is transmitted, moving from more costly FTTP deployment models to emerging Fiber-to-the-distribution point (FTTdp) models and now Fiber-to-the-Cabinet (FTTCab).

This, coupled with ADTRAN’s intention to increase the port density of G.fast equipment in the future, offers potential savings for large service providers for every 50 meters of additional customer reach.

"Providing fiber to every home or business in a given community can be a logistical and financial challenge. Rather than relying on fiber for the entire network, G.fast solutions such as ADTRAN’s utilize existing copper assets for the last step of the journey,” said Mike Galvin, managing director of service, strategy & operations at BT.

"This allows us to provide the ultra-fast broadband that customers demand, while reducing the time and cost of running fiber all the way to the premises,” said Galvin.

Eduard Scheiterer, senior vice president, research and development, ADTRAN, said the company’s continued investment in G.fast includes end-user service activation through reverse powering capabilities.

"We are also working with standards bodies like the Broadband Forum to develop open APIs and interfaces allowing simplified, rapid deployment into any broadband network, regardless of FTTx vendor or OSS incumbency,” said Scheiterer.

ADTRAN’s G.fast solutions support open Software-Defined Network (SDN) deployment models that ensure rapid plug and play deployment capability within the multi-vendor FTTx networks that exist today.

The broadband technology company claims over 100,000 sealed micro DSLAMs in FTTdp and FTTCab deployments to date.

Originally pubkished at www.telecomlead.com/telecom-equipment/adtran-says-60-telecoms-use-g-fast-broadband-solutions-66797

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The demand for higher speeds and greater bandwidth in the telecoms network is increasing at a breathtaking rate. In order to accommodate this demand, there requires a need to upgrade to 40G Ethernet links for switch to server and storage area network connections in data centers. This upgrading to 40G links ushers the widespread use of Finisar QSFP+ optics. This article discusses Finisar QSFP+ optics in details.

Finisar's broad product selection and innovative technology have attracted many consumers, and it has become an optical module manufacturer for some major networking equipment vendors worldwide. Finisar QSFP+ optics are capable of distances ranging from very short reach within a data center to campus, access, metro, and long-haul reaches. They feature outstanding performance over extended voltage and temperature ranges, while minimizing jitter, electromagnetic interference (EMI) and power dissipation. In a word, Finisar QSFP+ optics demonstrate themselves as the ideal choices for your Internet services.

Finisar QSFP+ supports highly reliable operations in data center networks, optimized for Finisar switching platforms. With rigorous qualification and certification testing, these hot-pluggable QSFP+ form factors enable high-speed data connectivity for networking applications. Here two Finisar QSFP+ are introduced: FTL4C1QE2C and FTL410QE1C.

Finisar's FTL4C1QE2C QSFP+ transceivers, compliant with the QSFP+ MSA and IEEE 802.3ba 40GBASE-SR4, are designed for use in 40G links over a single mode fiber (SMF) with the maximum link length of 10km. Fiberstore compatible Finisar FTL4C1QE2C, designed with built-in digital diagnostic functions, supports 41.2 Gb/s aggregate bit rates with duplex LC receptacles.

Similarly, Finisar's FTL4C1QE1C QSFP+ transceivers are also intended for use in 40G links over SMF. They feature a microprocessor and a diagnostics interface that provide performance information on the data link. These digital diagnostics functions help consumers monitor - in real-time - received optical power, transmitted optical power, laser bias current, transceiver input voltage and transceiver temperature of any transceiver in the network. These transceivers serve as the cost-effective tool for reliable performance monitoring.

Finisar 40G QSFP+ cables allow for great reliability and high performance. Finisar’s active optical cables (AOCs) accelerate data connectivity for storage, networking and high performance computing applications. Key advantages of Finisar’s AOCs include low weight for high port count architectures; small bend radius for easy installations; and low power consumption enabling a greener environment, thereby providing the lowest total cost solution for data centers. Quadwire, a 4-channel parallel AOC product, supports data center link lengths up to 100 meters for 40G links. It’s available in a point-to-point configuration using MSA compliant QSFP+ modules on each end, or a fan-out configuration with a QSFP+ module on one end and four separate SFP+ modules at the other end.

Finisar QSFP+ optics ensure system reliability after experiencing the rigorous qualification and certification testing, providing state-of-the-art performance with optimized Finisar solutions, and also eliminate issues related to transceiver incompatibility. With Finisar QSFP+ optics, it’s easy to carefully plan optical fiber network solutions, which deliver lower cost, consistent high performance, and pay-as-you-grow flexibility. With Finisar QSFP+ optics, you can go on network performance monitoring easily.

Finisar QSFP+ optics make flexible and simple 40G connectivity possible, while saving your money. You can try them. Fiberstore, as a professional manufacturer and supplier for optical fiber products, offers various Finisar QSFP+ optics with high quality and low cost, such as FTL4C1QE2C and FTL410QE1C mentioned above. Want to know more information about Finisar QSFP+ optics, you can visit Fiberstore.

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Along with the development of fiber technologies over the past a couple of years, tools for easier fiber connection have been invented—fiber optic connectors (or so-called "better mousetrap”). Given there are various fiber optic connectors (eg. ST, SC, LC, MPO/MTP) available for network designers to set up fiber connectivity in bandwidth-demanding applications, this article introduces MPO/MTP in details.

MPO/MTP technology with multi-fiber connectors ensures ideal conditions for establishing high-performance and high-speed data networks to handle bandwidth requirements. The term MTP is a registered trademark of US Conec used to describe their connector. The US Conec MTP product is fully compliant with the MPO standards. As such, the MTP connector is a MPO connector. The following passages will mention MPO only instead of MPO/MTP for simplicity.

To let readers gain a better understanding of MPO technology, MPO components introduction goes first followed by the applications of MPO technology.

MPO (multi-position optical) connector contains up to 24 fibers in a single connection. It’s available in a male version (with pins) or a female version (without pins). The pins ensure that the fronts of the connectors are exactly aligned on contact and that the endfaces of the fibers are not offset. MPO connector components mainly contain two parts: adapter and cable.

There are two types of MPO adapters based on the placement of the key: key-up to key-down, and key-up to key-up. In the former type, the key is up on one side and down on the other. The two connectors are connected turned 180° in relation to each other. In the latter type, both keys are up. The two connectors are connected in the same position in relation to each other. Just like what’s shown in the figure below.

MPO fiber cables are available in two primary types: MPO trunk cables and MPO harness cables.

MPO trunk cables are available in 12-144 counts. They serve as a backbone connecting the MPO modules to each other, intended for high-density applications.

MPO harness cables, also called MPO breakout cables or MPO fanout cables, are available in 8-144 counts. As terminated with MTP/MPO connectors on one end and standard LC/FC/SC/ST/MTRJ connectors (generally MTP to LC) on the other end, MPO harness cables provide a transition from multi-fiber cables to individual fibers or duplex connectors.

The remaining parts describe how MPO technology is utilized to permit successful migration from 10 GbE to 40/100 GbE.

It’s no doubt that converting or expanding existing infrastructure to accommodate higher bandwidth applications is more ideal and practical in data centers. In 10 GbE to 40 GbE/100 GbE migration, the most key point that should be kept in mind is the capacity expansion in which MPO modules are used to enable faster transmission. Many 40G QSFP transceiver modules utilize MPO technology for 40G links, among which the Cisco QSFP is the most widely-used module. Take Cisco for example, QSFP-40G-SR4 realizes 40G links over 850nm multi-mode fiber (MMF) with MPO-12 as its connector type.

In 40G to 100G migration, there requires the use of 24-fiber MPO cables. The existing 12-fiber connection can either be expanded with the addition of a second 12-fiber connection or can be replaced with the installation of a 24 fiber connection.

With these MPO components and technology applications, it’s easier for network designers to select the right MPO types to meet the bandwidth requirements. As a professional fiber optical product manufacturer and supplier, Fiberstore supplies various MPO modules and cables, including QSFP-40G-SR4 (one of Cisco QSFP products) mentioned above. You can visit Fiberstore for more information about MPO modules.

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The operators of the Southern Cross Cable Network say they have added 900 Gbps of capacity to their submarine network. The upgrade raises the undersea fiber-optic network's total network lit capacity to 5.8 Tbps. Meanwhile, the company also has improved its packet transport capabilities to enhance Carrier Ethernet service delivery.

Both initiatives benefited Ciena Corp. (NYSE: CIEN), which is the Southern Cross Cable Network's primary optical transport systems supplier. The Ciena 6500 is the workhorse optical platform for the submarine cable network (see, for example, "Southern Cross submarine fiber network jumps to 100G"). However, Ciena also delivered enhanced technology for other systems it has supplied for the network.

"While we have augmented our transmission by 900 Gbps per segment, we have also upgraded our key Ciena 5430 nodes to 15-Tbps OTN switching capability, a first for the region and a world first for a submarine cable operator as far as we are aware," detailed Southern Cross President & CEO Anthony Briscoe. "Southern Cross' key switching nodes are now capable of switching over 100 times Southern Cross' original segment capacity.

"Our latest expansion has also deployed Ciena's 200-Gbps per wavelength technology across our Hawaiian inter-island network in another world-first in technology activation, as well as continuing to leverage Ciena's flexible grid, GeoMesh, and 8D-2QAM technologies to maximize capacity and resiliency within our network while ensuring operational simplicity, scalability, and evolution toward software-defined networking (SDN)," Briscoe added.

Meanwhile, Southern Cross has decided to install the Ciena 8700 Packetwave packet switching platform as well. The systems will help the operator provide MEF CE2.0 compliant Carrier Ethernet packet transport services at data rates from 1 Gbps to 100 Gbps.

"Along with our existing key Internet data center access points such as Equinix in Sydney, CoreSite in San Jose, and the Westin Building in Seattle, these developments cement the Southern Cross position as the only single system provider of highly resilient innovative international capacity solutions between key data locations in Australia, New Zealand, the USA, and Fiji," asserts Southern Cross CTO Dean Veverka.

These recent upgrades, paired with previous enhancements, have extended the network's lifetime to at least 2030 while giving it a potential capacity of 14 Tbps, Southern Cross adds. Further network enhancements are likely, Briscoe indicates.

Originally published at www.lightwaveonline.com/articles/2016/01/southern-cross-adds-capacity-enhances-packet-transport.html

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Driven by the enormous rise in networking access devices and applications, the total bandwidth requirements are also growing accordingly. Networking devices are needed to accommodate the higher port density. To meet these demands, several cabling solutions have been developed by network designers. Commonly used cabling options include fiber optic cables, direct attach cables and active optical cables. Of course, there also exist some other cabling solutions, like copper RJ45. But this article gives detailed information about the former three.

Fiber optic cables are primarily divided into two types based on transmission media: single-mode fiber (SMF) and multi-mode fiber (MMF).

Single-Mode Fiber—SMF, usually in yellow, has a small 8-10 micron glass core and one pathway of light, leading to the more focused light toward the center of a core instead of bouncing it off the edge of the core like MMF. Therefore, SMF is more suitable for transmitting data over longer distances, typically used in long-haul network connections when combined with transceivers. Take QSFP-40G-LR4 for example, this Fiberstore QSFP-40G-LR4 module compatible with Cisco can realize 10km link lengths when running over SMF. The figure below shows what a QSFP-40G-LR4 transceiver looks like.

Multi-Mode Fiber—MMF, usually in orange, has a larger core and more pathways of light. With multiple pathways of light, MMF can gather more light and signals than single-mode ones within shorter distances. The typical applications of MMF include general data and voice fiber, such as bringing finer to the desk, and alarm system.

Direct attach cable (DAC), a kind of optical transceiver assembly, is a form of high speed cable with "transceivers” on either end used to connect switches to routers or servers. The "transceivers” on both ends of DACs are not real optics and their components are without optical lasers. This term, DAC, is used for copper cables that can be of the passive or active type. Nowadays, direct attach copper cables still have wide applications in telecommunications, especially in 40Gigabit links, owing to their interchangeability, low cost and fast data rates. Like direct attach passive copper cable, Cisco QSFP-H40G-CU3M product is just the QSFP to QSFP direct attach passive copper cable assembly designed for 40 Gigabit links. This QSFP-H40G-CU3M product listed on Fiberstore offers you a cost-effective solution for short solution.

Active optical cable (AOC) is a cabling technology that accepts same electrical inputs as a traditional copper cable, converts the electrical signal to the optical signal—known as an electrical-to-optical conversion (i.e. E/O) in the transceiver assembly. That is to say, AOC uses electrical-to-optical conversion on the cable ends to improve speed and distance performance of the cable while mating with electrical interface standard.

With these detailed information about cabling solutions, it’s easier for you to find what kind of cabling solution you choose to build and expand your existing networking infrastructure, so as to increase bandwidth and ensure you good network performance. Fiberstore is a leading manufacturer and supplier of fiber optical products, including cabling assembly structured in both fiber and copper, like QSFP-H40G-CU3M mentioned above. You can choose the cost-effective cabling option for networking connectivity according to specific situations at Fiberstore. Please not hesitate to contact us when you come into any puzzle or question!

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Today’s data centers have witnessed an unprecedented increase in computing bandwidth which is needed to drive network services, causing the never-ceasing evolution of Ethernet technologies to accommodate this high bandwidth need. And during this evolution, fiber optic cables are always preferred by users in network deployment for their longer link lengths and greater capacity, compared with their counterpart copper cabling solutions. Here, three key points are mentioned before establishing fiber optic links for your network performance, like fiber optic construction, fiber principles, and versus among different cable types.

Fiber optic cable is a cable made of glass and capped at either end with connectors. It cannot bear sharp bending or longitudinal stress because of its glass material. Thus, special construction techniques are used to allow the fiber to move freely within a tube. Usually fiber optic cables contain several fibers, a strong central strength member, and one or more metal sheaths for mechanical protection (image shown below). Some cables also consist of copper pairs for auxiliary applications. These cables are featured with low insertion loss and return loss, high durability (more than 500 times mating), as well as temperature stability (operating temperature: -20 to +75 ℃). For these characteristics, fiber optic cables are one of the fastest-growing transmission media in optical network systems.

Fiber optic cables’ delicacy and great ability to carry light over either short or long distances are owing to some fundamental physics concerning refraction and reflection of light. Since there exists differences in speeds that the light can travel through different materials, whenever a ray of light passes from one transparent medium to another, the light is affected by the interface between the two materials. Each material can be described based on its refractive index, which is the ratio of the speed of light in the material to its speed in free space. This relationship between these two refractive indexes determines the critical angle of the interface between the two materials.

Fiber optic cables are available in different types, such as breakout cable and distribution cable, indoor cable and outdoor cable.

Breakout cables are made of several simplex cables bundled together. These cables are used to carry fibers that have individual connectors attached, rather than being connected to a patch panel. They are designed to provide the ease of connector installation on optical fiber. Their typical use in fiber optical systems is for 40Gigabit links. Like QSFP+ breakout cable (fiber version), the QSFP to 4x SFP+ breakout active optical cable assembly offers a cost-effective interconnect solution for 40Gigabit links. Take Cisco QSFP-4X10G-AOC10M for example, Fiberstore compatible Cisco QSFP-4X10G-AOC10M runs over breakout active optical cable (AOC) for 40G interconnection. The following figure shows what the QSFP-4X10G-AOC10M product looks like.

Distribution cables have several tight-buffer cables bundled under the same jacket. They can be directly terminated. However, because distribution cables are not individually reinforced, they need to be broken out with a "breakout box” or terminated inside a patch panel or junction box.

Indoor or outdoor cable uses dry-block technology to seal ruptures against moisture seepage and gel-filled buffer tubes to halt moisture migration, suitable for aerial, duct, tray, and riser applications.

After discussion, maybe you have obtained a better understanding of fiber optic cables, which helps you to establish your fiber optic links. As a leading fiber optical product manufacturer and supplier, Fiberstore offers various kinds of fiber optic cables, including QSFP+ breakout cable mentioned above (available in both copper and fiber versions). For more information about fiber optic cables, you can visit Fiberstore.

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It’s no doubt that 10Gbps speeds for individual streams have been routinely reached under today’s networking environment. And for better network performance, the existing bandwidth has been generated to 40Gbps. Among various network devices designed for 40 Gigabit Ethernet (GbE) links, 40G QSFP+ transceivers are of vital importance in driving the bandwidth to a mounting point. Here this publication puts its focus on the Juniper 40G QSFP+ transceivers, which ensure high density and low latency, as well as small power consumption.

Firstly let’s figure out what is the 40G QSFP+ transceiver.

The Quad Small Form-factor Pluggable (QSFP) is a compact, hot-pluggable transceiver used for data communications applications. The 40G QSFP+ transceiver is a parallel fiber optical module, using four independent optical transmit and receive channels. It uses a 4 x 10Gb/s link configuration for a 40Gb/s port, offering users high-density 40 Gigabit Ethernet connectivity options for high-performance networks. QSFP+ transceivers can be applied in switches, routers and data center applications. Compared with SFP+ transceivers, QSFP+ transceivers increase the port-density by 3x-4x. Besides, they still enjoy the following features.

Juniper QSFP+ is a Multi-Source Agreement (MSA) for high speed application, such as 40G-BASE, which provide four channels of data in one pluggable interface. Each channel is capable of transferring data at 10Gbps and supports a total of 40Gbps. Juniper 40G QSFP+ transceivers enjoy the following listed key features:

• QSFP+ MSA, SFF-8436 Compatible;
• Four Independently Addressable Transmit and Receive Channels;
• Highly Compact and Electrically Hot-pluggable;
• Digital Diagnostic Monitoring (DDM) Interface for Better Module Management;
• Simplified Heat Management With Reduction in Power Consumption;

After discussion on several key features of Juniper 40G QSFP+ transceivers in general, here goes the detailed information about two types of Juniper 40G QSFP+ transceivers: Juniper 40G QSFP+ LX4 transceiver and Juniper 40G QSFP+ LR4 transceiver.

The Juniper QSFP+ LX4 transceiver has four 10 Gbps channels, each of which can transmit and receive simultaneously on four wavelengths over a multi-mode fiber (MMF) strand. The result is an aggregated duplex 40 Gbps link over a duplex of two MMF strands. Using duplex LC connectors, QSFP+ LX4 connections can reach 100 meters on OM3 MMF or 150 meters on OM4 MMF. What’s more, this Juniper QSFP+ LX4 transceiver (JNP-QSFP-40G-LX4) addresses the challenges of fiber infrastructure by providing the ability to transmit full-duplex 40Gbps traffic over one duplex MMF cable with LC connectors. In other words, the Juniper QSFP+ LX4 transceiver, a short-reach optical transceiver that delivers 40Gbps over duplex OM3 or OM4 MMF, allows 40Gbps connectivity to connect directly to the 10Gbps fiber and fiber trunk.

For Juniper 40G QSFP+ LR4 transceiver, JNP-QSFP-40G-LR4 enables high speed 4 x 10G operations. It’s designed for use in 40 Gigabit Ethernet links over single mode fiber (SMF) with Duplex LC connectors. Compliant with the QSFP+ MSA and IEEE 802.3ba, JNP-QSFP-40G-LR4 is RoHS-6 compliant with built-in DDM interface. Fiberstore compatible Juniper JNP-QSFP-40G-LR4 is intended to support up to 10km over a standard pair of G.652 SMF.

The Juniper 40G QSFP+ transceivers are well suited for Infiniband, 40GBASE-SR4, 40GBASE-LR4 applications, suitable for short reaches among switches, routers and data center devices. Combined with right fanout cables, these modules can interface up to four SFP+ transceivers.

Juniper 40G QSFP+ transceivers boast of high-density features and provide users with 40Gbps connectivity for better network performances. Fiberstore supplies various Juniper 40G QSFP+ transceivers which are quality and performance assured, such as JNP-QSFP-40GE-LX4 and JNP-QSFP-40G-LR4 mentioned above. Please feel free to contact us for more information about Fiberstore 40G QSFP+ transceivers compatible with Juniper.

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Today’s Data Center includes a large number f bandwidth-intensive devices, like network servers, data storage systems, virtualization appliances, and backup devices. These devices require reliable cabling infrastructure to meet the increasing demands for higher-performance, -speed and -density. There are mainly two media available when planing careful structured cabling: fiber optics and copper. Followed is an overview of these two data transmission media.

Fiber optic cables, also called fiber patch cables, fiber optic patch cords, or fiber jumper cables, are made of pure glass. These layers contain cladding, stranded fibers and a jacket. Fiber optic cables terminate with optical connectors on one or two cable ends, deployed to link optical equipment and components to achieve data transfer and Internet connectivity between devices. This medium allows movement of data transfer at high speed and with great distances. Besides, their delicacy and ability in transmitting data earn trust and reliability from users.

Fiber optic cables are commonly referred to single-mode fibers (SMFs) and multi-mode fibers (MMFs). SMFs, usually in yellow, have one core and one pathway of light, which leads to more focused light at the center of a core. Thus, they are more suitable for transmitting data over longer distances than MMFs. As for MMFs, usually in orange, they have a larger core diameter and multiple pathways of light, so they can gather more light and signals than single-mode ones over shorter distances. Both SMFs and MMFs are widely used for 10G, 40G and 100G transmission, when combined with transceivers. Take 40G transmission for example, QSFP-40G-LR4 transceiver is designed for SMFs. Fiberstore compatible Cisco QSFP-40G-LR4 module supports link lengths of 10km on SMF for 40G optical links.

Copper cable, in most times, refers to twisted-pair copper cable. This medium consists of several copper wires surrounded by insulators and is designed to transmit electronic signals. The two insulated wires are twisted together to form a pair, and then the pair forms a balanced circuit.

Twisted-pair copper cable comes in two versions: shielded twisted pair (STP) and unshielded twisted pair (UTP). UTP cables are easier to complement, more wildly used and cheaper than their counterparts, STP cables. UTP cables are commonly used in Ethernet networks, while STP cables are in Token Ring networks. The image below show UTP cable (left) and STP cable (right).

Cables are all defined with characteristics, and fiber patch cables and twisted-pair copper cables are no exception. Attenuation and alien crosstalk are the two most important aspects for cables.

Attenuation means the loss or reduction in signal strength during transmission. In addition to distance, attenuation can also be added by the higher temperatures, metal conduits, as well as the low quality of cables. As for fiber patch cables, attenuation decreases with frequency and the lowset attenuation is happens at 1550mn, while the attenuation in copper cables increases with frequency, thus the higher the speed, the greater the signal loss.

Unwanted signal coupling from one component to another is called alien crosstalk (AXT). Fiber patch cables are free from this characteristic, AXT. In contrast, twisted-pair copper cables are sensitive to signals from other surrounding components.

Both fiber optic cables and copper cables play an important role in transmitting data at high speed. Fiberstore supplies various kinds of high-quality fiber optic cables and copper cables for your fast networks, including SMFs and MMFs mentioned above. You can visit Fiberstore for more information about fiber optic cables and copper cables.

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Nokia reports the Autorit des Marchs Financiers (AMF), the French stock market authority, has published interim results of the initial offer period of Nokia's public exchange offer for Alcatel-Lucent securities in France and in the United States. The results indicate Nokia now holds almost 80% of Alcatel-Lucent's shares, after announcing its intention to acquire the France-based systems house last April (see "Nokia pulls trigger on Alcatel-Lucent buy").

If the AMF confirms these interim results as expected January 5 and assuming the full exercise of convertible bonds and settlement of the offer January 7, Nokia will hold 79.32% of the share capital and at least 78.97% of the voting rights of Alcatel-Lucent. This result would enable Nokia to begin integration of Alcatel-Lucent, with the first day of joint operation targeted for January 14, 2016.

Meanwhile, in accordance with French law, Nokia will reopen the tender process in France and the U.S. in hopes of buying the rest of the outstanding shares. The reopened tender will begin within 10 French trading days of the final AMF report. If it attains 95% share ownership, Nokia says it intends to squeeze out the remaining shareholders.

"We are delighted that the offer has been successful, and that Alcatel-Lucent's investors share our confidence in the future of the combined company," said Rajeev Suri, Nokia's president and CEO. "We will move quickly to combine the two companies and execute our integration plans. As of January 14, 2016, Nokia and Alcatel-Lucent will offer a combined end-to-end portfolio of the scope and scale to meet the needs of our global customers. We will have unparalleled R&D and innovation capabilities, which we will use to lead the world in creating next-generation technology and services."

Nokia reiterated its intention, subject to Nokia shareholder approval, to execute a EUR 7 billion program to optimize its capital structure and return excess capital to Nokia shareholders once the transaction closes. The move is planned to include approximately EUR 4 billion in distributions to Nokia shareholders; remaining holders of Alcatel-Lucent securities will not receive distributions.

Originally published at www.lightwaveonline.com/articles/2016/01/nokia-nears-closing-of-alcatel-lucent-acquisition-holds-nearly-80-of-alcatel-lucent-shares.html

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Over the past few years, there appeared a boom in the adoption of 10/100M Ethernet or Fast Ethernet due to the low cost and compatibility with existing local area networks (LANs). Driven by growing high-quality networking applications and increasing bandwidth-hunger delivery demands, this Ethernet LAN evolved even rapidly and then Gigabit Ethernet (1000M Ethernet) appeared. Actually, Gigabit Ethernet has proved itself as a suitable choice to increase bandwidth requirements for growing networks in high speed data communication.

Just as what has been expressed in the paragraph above, Gigabit Ethernet (GbE or 1 GigE) is the evolutionary fruit of Ethernet standard. In computer networking, GbE is a term describing various technologies for transmitting Ethernet frames at a rate of a gigabit per second (1,000,000,000 bits per second), as defined by the IEEE 802.3-2008 standard. It came into use in 1999, gradually supplanting Fast Ethernet in wired local networks, since in such areas GbE performed considerably faster.

Gigabit Ethernet standards define a Gigabit Media Independent Interface (called the GMII) to the Ethernet Media Access Control (MAC) layer, management, repeater operations, topology rules, and four physical layer signaling systems: 1000BASE-SX (short wavelength fiber), 1000BASE-LX (long wavelength fiber), 1000BASE-CX (short run copper) and 1000BASE-T (100-meter, four-pair Category 5 UTP). Namely, Gigabit Ethernet can run over three media: fiber optic patch cable (single-mode fiber or SMF, multi-mode fiber or MMF), shielded balanced copper cable and Category 5 UTP. The figure below shows the relationship of the various members of the Gigabit Ethernet technology family.

1000BASE-LX is specified to work over a distance of up to 5km over 10µm SMF. It can also run over all common types of MMF with a maximum segment length of 550m.

1000BASE-SX uses shortwave laser for operation over MMF. The maximum length of segment supported by 1000Base-SX is 550 meters. Like GLC-SX-MM-RGD module, Fiberstore compatible Cisco GLC-SX-MM-RGD is designed for 550m transmission with a data-rate of 1.25Gbps/1.063Gbps.

1000Base-CX is an initial standard for Gigabit Ethernet connections with maximum distance of 25 meters using balanced shielded twisted pair. In practice, 1000BASE-T has succeeded it for general copper wiring use.

1000 Base-T transmits signal over four pairs of CAT5 untwisted pair cables (UTP). Each 1000BASE-T network segment can be a maximum length of 100 meters. It can provide speed of 1000 Mb/s-10 times the speed of Fast Ethernet- over CAT5 UTP.

As a professional fiber optical product manufacturer and supplier, Fiberstore supplies a broad selection of these cables for Gigabit Ethernet solution, such as SMF, MMF, and copper. These cables are all quality assured and cost-effective. Besides, active and passive copper cables are also available in Fiberstore. Like the Cisco QSFP-H40G-ACU10M product, this QSFP-H40G-ACU10M listed on Fiberstore runs over active copper cable for 40G links.

With the help of these cables, you can enjoy the flexibility of cabling assemblies, as well as the network bandwidth without limit to the data transfer speed. Fiberstore cables give you fast network speed while helping you save your money. You can visit Fiberstore for more information about Gigabit Ethernet cabling solutions.

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