Talk About MPO Connector

As high-density cabling in data center has become a trend, network components characterized by saving space become popular among data center managers. There is a type of multi-fiber connector—MPO connector, which is now widely used around the world. MPO connector not only allows for more fiber ports per unit of rack space, but also satisfies the need of parallel optical interconnections for multi-fiber connection. This article is going to introduce the detailed information about MPO connector.

Structure of MPO Connector

Each MPO connector has a key on one side of the connector body. When the key sits on top, this is referred to as the key up position. On the contrary, when the key sits on bottom, we call it key down position. Each of the fiber holes in the connector is numbered in sequence from left to right, and we call these fiber holes as positions, or P1, P2, etc. Besides, as shown in the following figure, there is a white dot on the connector body to designate the position 1 side of the connector when it is plugged in. Generally, MPO connector is pin and socket connector, which requires a male side and a female side. From the figure below we can find that MPO male connector has pins, while MPO female connector has no pins.

MPO Connector Types

Originally designed for ribbon fiber, MPO connector is available in 12, 24, 48 and 72 fiber variants. Generally, there are two popular MPO connector types: 12 fiber MPO connector and 24 fiber MPO connector. The following part will introduce these two types of MPO connectors to you.

12 Fiber MPO Connector

In theory, the 12 fiber MPO connector can deliver 6x10G transmit fibers and 6x10G receive fibers. However, it actually only delivers 40G since the transceivers and the equipment are only capable of supporting 40G data rates. That means 33% fibers of the connector are not being used, only 8 fibers are being used at the transceiver while the other 4 fibers are just spares. From the figure below, you can have a better understanding of this.

12 fiber MPO connector

Accommodating 12 fibers, the 12 fiber MPO connector provides up to 12 times the density, thereby it can save space in the rack. It is the first connector which has enough repeatable performance to be accepted in data centers. If you build a backbone with a 12 fiber MPO connector, basically you can put any connection on the end to be future proofed, such as LC, SC, etc. Thus most of data centers choose 12 fiber MPO connector cabling in the backbone and MPO-LC harnesses cable connecting to equipment like switches and servers. Many equipment today still has LC transceiver interface, therefore the harness is required to convert from MPO in the backbone to LC at the port.

24 Fiber MPO Connector

With development of data centers, many data center managers come across the problem that the promoted 12 fiber MPO connector no longer matches the requirement of the data centers. Every equipment applied in the data center is either 40G (8 fibers) or 100G (24 fibers). 12 is not divisible by 8, but 24 is. If you combine 2×12 fiber MPO connectors in the backbone, you can connect 3×8 fiber MPO connectors with zero fiber waste at the switch. The 24 fiber MPO connector has similar performance to the 12 if not exactly the same.

24 fiber MPO connector

As shown in the above figure, the 24 fiber MPO connector has two rows of 12 fibers. And this additional row of fibers require an increase in the spring force to push all of those fibers together, actually double what you need for 12. With the same size as a 12 fiber MPO connector, the 24 fiber MPO connector has double the amount of fibers and reduces the amount of cable required at the back end because a 24 fiber cable is only marginally bigger than a 12 fiber cable. Moreover, when you can just have 1×24 fiber MPO connector converting to 3×8, there is no need to combine 2×12 fiber MPO connectors to make 3×8. The 24 fiber MPO connector can also satisfy the demand for 100G data rates over a single connector and 20 fibers are used for 100G (10x transmit and 10x receive).

Conclusion

MPO connector delivers the optical, mechanical and environmental performance that service providers need to expedite the addition of fiber capacity and to support higher data-rate services. It plays an important role in the high-density cabling solutions. I hope after reading this article, you can have in-depth understanding of MPO connector.

Difference Between 40G QSFP+ Transceiver with LC Interface and MTP/MPO Interface

Data transmission with higher density and bandwidth has become the trend under present networking environment. With 40 Gigabit Ethernet commonly deployed in most data centers, various network devices designed for 40 Gigabit Ethernet (GbE) link are available on the market. Among them, 40G QSFP+ transceivers play an important role in driving the bandwidth to a mounting point. There are mainly two interfaces adopted by 40G QSFP+ transceivers—MTP/MPO and LC. What is the difference between these two interface types? This article will have an analysis of the 40G QSFP+ transceivers with LC interface and 40G QSFP+ transceivers with MTP/MPO interface.

40G QSFP+ transceiver with MTP and LC interface

40G QSFP+ Transceivers With LC Interface

From the figure below, we can easily understand the working principle of 40G QSFP+ transceivers with LC interface. In the transmit side, 4 channels of 10G serial data streams at different wavelengths are passed to laser drivers. The laser drivers control directly modulated lasers (DML) with wavelengths. Then the output of the four DMLs are optically multiplexed to a SMF through an industry-standard LC connector, combining as 40G optical signal. In the receive side, the 40G optical signal is demultiplexed into four individual 10G optical data streams at different wavelength. And each wavelength light is collected by a discrete photo diode and amplified by a TIA, and then outputted as electric data. In this process, a 4-wavelength CWDM multiplexer and demultiplexer is used over a pair of single-mode fibers. For transmission distance of this type of 40G QSFP+ transceiver, take 40G LR4 QSFP+ transceiver as an example, it can support an optical link length up to 10 kilometers over the single mode fiber.

40G QSFP+ transceiver LC interface working principle

40G QSFP+ Transceivers With MTP/MPO Interface

We can easily understand the working principle of 40G QSFP+ transceiver with MTP/MPO interface from the figure below. In the transmit side, the transmitter converts parallel electrical input signals into parallel optical signals through the use of a laser array. Then the parallel optical signals are transmitted parallelly through the multimode fiber ribbon terminated with MPO/MTP fiber optic connector. In the receive side, the receiver converts parallel optical input signals via a photo detector array into parallel electrical output signals. Generally, 40G QSFP+ transceivers with MTP/MPO interface are utilized for short distance transmission over multimode fiber (MMF), like 40G SR4 QSFP+ transceiver, it can support a link length up to 100 meters on OM3 cable and 150 meters on OM4 cable.

40G QSFP+ transceiver with MTP MPO interface working principle

Note: there are also some 40G QSFP+ transceivers with MTP/MPO interface supporting long distance transmission over SMF. For example, 40G LR4 PSM QSFP+ transceiver, a parallel single-mode optical transceiver with an MTP/MPO fiber ribbon connector, it offers four independent transmit and receive channels, each capable of 10G operation for an aggregate data rate of 40G over SMF. That is to say, eight single-mode fibers are used to achieve parallel transmission, with transmission distance up to 10 kilometers. From the perspective of cost, this kind of 40G QSFP+ transceivers cost more than 40G QSFP+ transceivers with LC interface. Besides, in the data center fiber infrastructure, MTP patch panel has to be used to accommodate MTP cables, which would cost more than LC connectors and regular SMF cables.

4x10G Connectivity

For the 40G QSFP+ transceivers with LC interface, they cannot be split into 4x10G as they use 4 wavelengths on a pair of single-mode fibers and do not lend themselves to “splitting” into 4 pairs without substantial complexity to split out the wavelengths. For the 40G QSFP+ transceivers with MTP/MPO interface, they can be used in 4x10G connectivity via an external 12-fiber parallel to 2-fiber duplex breakout cable, which connects the 40G module to four 10G optical interfaces.

Conclusion

Generally speaking, the 40G QSFP+ transceivers with LC interface are used for long distance transmission over single-mode fiber (SMF), and 40G QSFP+ transceivers with MTP/MPO interface are utilized for short distance transmission over multimode fiber (MMF). However, for some 40G QSFP+ transceivers with MTP/MPO interface, such as 40GBASE-LR4 PSM QSFP+ transceiver, it can support long distance transmission over SMF. Besides the examples discussed above, there are some other types of 40G QSFP+ transceivers provided by FS.COM, such as 40GBASE-CSR4 QSFP+, 40GBASE-PLR4 QSFP+, 40GBASE-ER4 QSFP+ and so on. If you want to know more details, please visit our site.

Solid Cable vs. Stranded Cable

As we know, bulk Ethernet cable can be divided into unshielded twisted cable (UTP) and shielded cable (STP) according to the structure of shielding. Apart from this, bulk Ethernet cable can also be divided into solid cable and stranded cable. These two types of bulk Ethernet cables have their individual features and advantages. As they can be easily found in Ethernet network applications, how much do you know about them? This article will mainly make a comparison between solid cable and stranded cable.

Overview of Solid and Stranded Cable

Solid cable is made up of a single and solid wire per conductor. That means in four twisted pairs cat6 cable reel, there are a total eight solid wires. This type of cable is used for home electrical cabling, cabling for breadboards and other situations where cables are not required to be constantly flexed. Stranded cable consists of multiple smaller-gauge wires wrapped around each other in each conductor. That is to say in a four twisted pairs Ethernet cable with seven strands per conductor, there are a total of fifty-six wires. This type of cable is typically used in situations where cables need to be routed into tight spaces or experience frequent flexing or vibrations. To better understand the difference of the inner structure between solid cable and stranded cable, here is a figure for you.

Solid cable and Stranded Cable

Comparison Between Solid Cable and Stranded Cable

With different structural designs, both solid cable and stranded cable have advantages and disadvantages. Hence, the following part will focus on the advantages and disadvantages of these two types of cables.

Advantages and Disadvantages of Solid Cable

Solid cable is often favored because of its cheaper production costs. It is simple but quite durable. With single and solid wire, solid cable is very easy to produce. Solid cable also has a much more compact diameter compared to stranded cable. Though the sized is reduced, it still has the same carrying ability as stranded cable. In addition, solid cable is less likely to fail due to the corrosion. However, one of the main problems with solid cable is that it is typically only available in small gauges. Also, if there is constant flexing or vibration, the cable would eventually wear down and break, resulting in the need for a replacement. Therefore, solid cable is not optimal for applications like robotics or vehicles that require a considerable amount of movement. The figure below shows the detail information about gray solid cat6 bulk cable 1000 ft from FS.COM and the price is about US$ 130.00, which is really a cost-effective option.

product datails about cat6 bulk cable 1000 ft

Advantages and Disadvantages of Stranded Cable

Stranded cable is easier to route in comparison to solid cable. It is very flexible. And stranded cable can withstand an incredible amount of vibrations and flexing without fatiguing and breaking. As a result, you won’t have to replace your stranded cables as often as will be necessary with solid cable. But stranded cable is more expensive. It is more costly to produce due to the more complex manufacturing process that is required to develop these intricate wires. Also, stranded cable is much more likely to fail as a result of corrosion from capillary action. In addition, stranded cable has a higher attenuation, so it is not suitable for long runs.

Conclusion

With the diversity and popularity of the bulk Ethernet cable, it is critical to choose the right type of cable for the network deployment. Like the two types of Ethernet cables mentioned above, the solid cable is less flexible but cheaper than the stranded cable, and it is less likely to fail due to the corrosion. If you want to make a permanent cabling, then the solid cable is a good choice for you which will save you a lot. But if your cabling network needs to move cables constantly, then you are strongly suggested to choose the stranded cable.

Understand 10GBASE-T in Depth

Today, the Ethernet cabling system market is dominated by 10G links. Although fiber optic cables become popular with the advantages of high data transmission rate and low latency, many IT departments still use copper cabling for switch-to-switch or switch-to-server connections in 10G Ethernet applications. As one major copper cabling technology applied for 10GbE, 10GBASE-T was released by IEEE 802.3an in 2006 which specifies 10Gbps data transmission over four-pair copper cabling. Then, how much do you know about it? This article will guide you to understand 10GBASE-T in depth from five aspects—reach, backward compatibility, power consumption, latency and cost.

Reach

10GBASE-T is able to reach transmission distances up to 100 meters, and Cat6, Cat6a, Cat7, these three types of copper cables are commonly used with the 10GBASE-T standard. Cat6 bulk cable can perform at the bandwidth of up to 250 MHz, but it may reach only 55 meters at the speed of 10Gbps and 33 meters in high crosstalk conditions; Cat6a bulk cable is defined at frequencies up to 500MHz, and it can support the transmission distance over 100 meters at the speed of 10Gbps; Cat7 bulk cable can deliver 10G performance up to 600 MHz and at a distance of up to 100 meters. Here is a figure of a roll of cat6 cable.

roll of cat6 cable

Backward Compatibility

We know that Cat6 bulk cable, Cat6a bulk cable and Cat7 bulk cable are backward compatible with the Cat5 and Cat5e bulk cable standards, so these three types of cables can also be used for 10BASE-T, 100BASE-T and 1000BASE-T applications, though a little overqualified. Moreover, 10GBASE-T is backward compatible with 1000BAE-T. Therefore, 10GBASE-T can be deployed in preceding 1GbE switch infrastructures in data centers that are cabled with Cat6, Cat6a or Cat7 cabling. This enables data center managers to save costs while upgrading the network to 10GbE.

Power Consumption

According to the study, the early physical layer interface chips (PHYs) consumed too much power for widespread adoption. The original gigabit chips were roughly 6.5 Warts per port. With the process of improvements, the chips are now under 1 Wart per port. In addition, the PHYs benefit a lot from the latest manufacturing processes in 10GBASE-T. And the technology will continue to reduce the power consumption of PHYs.

Latency

Depending on Ethernet packet size, the latency for 1000BASE-T ranges from below 1μs to over 12μs, while 10GBASE-T’s latency ranges from just 1μs to less than 4μs—a much tighten latency range. And with a larger packet size, 10GBASE-T’s overall throughput offers an advantage over 1000BASE-T, and the latency for 10GBASE-T is more than three times lower than that of 1000BASE-T. The 1μs latency of 10GBASE-T is of no consequence to most users. Only the most latent-sensitive applications such as High Performance Computer (HPC) or high frequency trading systems would be affected by normal 10GbE latency.

Cost

As for cost, copper cables are cheaper, which is one reason for their wide applications. Take cables of FS.COM for example, Cat6 cable 1000 ft is about US$ 130.00; Cat6a cable 1000 ft is about US$ 180.00; Cat7 cable 305m is about US$ 600.00. Though 10G SFP+ DAC Twinax Cable is about US$ 42.00, from the perspective of structured cabling, it has a limited distance (up to 10m), and is not as flexible or cost-effective as 10GBASE-T.

Conclusion

From the above content, we can learn that 10GBASE-T offers the lowest cost media, and is backward compatible with preceding 1GbE networks. It can not only satisfy the increased bandwidth needs, but also greatly simplify the network and lower power consumption by replacing multiple gigabit connections with a single or dual-port 10GbE connection. Hence, it is an idea choice for 10G Ethernet copper cabling. And I hope after reading this article, you can have a better understanding on 10GBASE-T. FS.COM provides cost-effective solution for your 10BASE-T Ethernet network deployment. If you want to know more details, please visit our site.

Difference Between Straight-Through Cable and Crossover Cable

It is well known that bulk Ethernet cable consists of four twisted pairs of copper wires and utilizes them to support data transmission between devices. To meet the demand of increasingly higher data rates and larger bandwidths, Ethernet cables have been upgraded constantly, from cat5, cat5e, cat6, cat6a to cat7. Although various types of Ethernet cables look the same, the internal wiring scheme distinguishes. With different wire arrangements inside the cables, Ethernet cables can be divided into straight-through cables and crossover cables. Then, what is the difference between them? This article will tell the answer.

Different Wiring Standards for Wire Arrangements

Before discussing the difference between straight-through cable and crossover cable, it is necessary to learn about two wiring standards—T568A and T568B, which can help you better understand the different wire arrangements inside these two types of cables. T568A and T568B wiring standards are recognized by ANSI, TIA and EIA for wiring Ethernet cables. Generally speaking, T568B is more widely used than T568A. And T568B is regarded as the default wiring scheme for twisted pair structured cabling. Here is a figure of T568A and T568B wiring standards, from which we can easily find that the only difference between T568A and T568B is the orientation of the green and orange wire pairs.

T568A and T568B

Comparison of Straight-Through Cable and Crossover Cable

As mentioned above, straight-through cable and crossover cable are designed with different wire arrangements for serving different purposes. Hence, the following part will focus on the comparison of these two types of cables from these two aspects.

Different Wire Arrangements

Straight-through cable uses one wiring standard. That means both ends of one straight-through cable use T568A wiring standard or T568B wiring standard. As for crossover cable, it uses two wiring standards: one end uses the T568A wiring standard, and the other end uses the T568B wiring standard. The internal wiring of crossover cables reverses the transmit and receive signals. For a better understanding of inner wire arrangements of straight-through cable and crossover cable, here are two figures for you.

Straight-through cable

Crossover cable

Different Applications

Straight-through cable is the most common type which is easy to find in stores. It is used to connect different type of devices, such as connecting a computer to a switch/hub’s normal port or a cable/DSL modem’s LAN port; a router’s WAN port to a cable/DSL modem’s LAN port; a router’s LAN port to a switch/hub’s uplink port (normally used for expanding network); 2 switches/hubs with one of the switch/hub using an uplink port and the other one using normal port. While crossover cables may be a little harder to find since they aren’t used nearly as much as straight-through cables. They are usually used to connect the same type of devices, like connecting 2 computers directly; a router’s LAN port to a switch/hub’s normal port (normally used for expanding network); 2 switches/hubs by using normal port in both switches/hubs.

Conclusion

Straight-through cable and crossover cable are structured with different wire arrangements and used for different applications. The straight-through cable is usually used for connecting two different kinds of devices, while the crossover cable is commonly used to connect the same type of devices. If you want to distinguish these two types of cables, you can just have a look at the order of the colored wires inside the RJ45 connector. If the color orders of the wires are the same on both ends, it means it is a straight-through cable. If not, it’s mostly like a crossover cable or there may be a wiring error inside the cable. At present, straight-through cable is much more popular than crossover cable and is widely used by people. FS.COM provides a full range straight-through bulk Ethernet cables with many colors and lengths options, such as red cat5e cable 1000 ft. If you want to know more details, please visit our site.