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- Instructions for Building a Copper Network at Home
- Picking the Proper Copper Patch Panel
- Considerations for Deploying a Wired Home Network
- Patch Panel—the Traffic Light for Cabling
- Comparison of Cat5e and Cat6 Ethernet Cable

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 Straight-Through vs. Crossover Cable Alerter l'administrateur Recommander à un ami Lien de l'article 

It is well known that network patch cable can be commonly wired as straight-through or crossover cable, used for data transmission. Both of these two network patch cables are made up of four pairs of high performance twisted wires with different colors, terminated by the RJ45 keystone jacks at each side of the cables. As for their applications, they are designed for serving different aims, with different wire arrangements inside their cables, which will be introduced in the following text for guiding you to pick the most proper one for deploying you network.

Different Wiring Standards for Wire Arrangements

Before discussing the differences between the straight-through and crossover cable, it is necessary to introduce two wiring standards, T568A and T568B, for better understanding the different wire arrangements in each kind of the cable. These two kinds of wiring standards are recognized by ANSI, TIA and EIA for wiring the network patch cables. Generally, the T568B wiring standard is more widely used than the T568A wiring standard, as the default wiring scheme for twisted pair structured cabling. If you are unsure of which to use, then choose T568B to arrange the wires inside the cable.

T568A and T568B Wiring Standard

In general, there are eight colored wires in a straight-through or crossover cable, which should be arranged according to the corresponding order of the wiring standard T568A or T568B. That’s to say, the wires with different colors should be terminated in the right positions of the RJ45 keystone jack where the wire colors and the colors in the RJ45 keystone jack are the same, as shown in the figure above.

Comparison of Straight-Through and Crossover Cable

When choosing the network patch cable in the store, you’ll easily find the straight-through cable that is commonly used to connect computers to hubs or switches. While the crossover cable with the function of connecting a computer to another computer should be a little hard to find since this kind of network patch cable are not so commonly used as the previous one. But what are the differences between the straight-through and crossover cable? Let’s talk about this topic.

Different Wire Arrangements

As mentioned above, these two kinds of network patch cables have different wire arrangements. For a straight-through cable, there should be only one wiring standard used. It means that both ends of one straight-through cable can be only wired according to T568A wiring standard or T568B wiring standard. Since T568B wiring standard is more popular, here offers the example of a straight-through cable with T568B wiring standard in the following figure. As for the crossover cable, it is designed with two wiring standards in both ends of the cable. In simple words, if there is a RJ54 keystone jack with T568A wiring standard in one end of the crossover cable, there must be a RJ54 keystone jack with T568B wiring standard in the opposite end, as shown in the following figure.

Straight-Through and Crossover Cable
Different Applications

The two kinds of network patch cables are available in the market, used for different applications. As for the straight-through cable, it is applied in local area networks to connect different kinds of devices, for instance, connect a computer to a switch/hub's normal port or a cable/DSL modem's LAN port. It can be an alternative to wireless connections where one or more computers access a router through a wireless signal. As for the crossover cable, it's usually used to connect same type of devices, such as, connect two computers directly, connect two switches/hubs by using normal port in both switches/hubs.


After discussion, we can concluded that the straight-through and crossover cable are designed with different arrangements, serving for different applications. The straight-through cable is usually used for connecting two different kinds of devices, while the crossover cable is highly recommended in the applications where same kind of devices need to be connected. If you want to distinguish the two kinds of cables, you can just check the color orders for the wires inside the RJ45 keystone jacks at both ends of the cables. If the color orders of the wires are the same on both ends, it means the network patch cable is a straight-through cable. If not, it must be a crossover cable or there may be a wiring error in the cable.

  Aucun commentaire | Ecrire un nouveau commentaire Posté le 04-01-2017 à 09h03

 How to Make the Ethernet Patch Cable at an Exact Length? Alerter l'administrateur Recommander à un ami Lien de l'article 

Are the Ethernet patch cables you purchase from the local or online stores always at the proper length? Or not so suitable for your network because they are too long or too short that don’t meet your expectations? Have you ever considered making the improper Ethernet patch cable into a suitable one by yourself, so that you can deploy your network by using you own Ethernet patch cable and save a lot of money, time and space? In fact, terminating the Ethernet patch cables is not so difficult but very useful for fast network deployment, which will be presented in the post. Meanwhile, there are several important things you should take into consideration before making the Ethernet patch cable termination, which will be also illustrated in details. Hope these information will guide you to make your own Ethernet patch cable and then deploy your Ethernet network in a very fast, smooth and cost effective manner.

Selecting a Proper Ethernet Patch Cable

Before making the Ethernet patch cable termination, you should choose one kind of Ethernet patch cable which is most suitable for your network, since there are various kinds of Ethernet patch cables available on the market, such as, cat5, cat5e, cat6, cat6a, cat7, etc. Considering that cat5e, cat6 and cat7 patch cable are the most commonly used ones at present, both of which will be introduced the following text.

cat5e, cat6 and cat7 patch cable

As an upgrade version of cat5 patch cable, cat5e patch cable has the ability to support gigabit speed, allowing for a faster, more reliable and steady network. It is much commonly used in home and office applications. As for cat6 patch cable, it is an enhanced version of cat5e patch cable that has much more sophisticated structure, as shown in the above figure. It is an ideal solution to face future-proof network that supports the transmission speed up to 10 gigabit with a long transmission distance. In contrast to cat5e and cat6 patch cable, cat7 patch cable is a kind of shielded Ethernet cable that has a great improvement in the capacity and reliability. It is more expensive since it has been the most durable and longer-lifespan Ethernet patch cable at present. As for the structural differences among cat5e, cat6 and cat7 patch cable, it is very easy to learn from the above figure.

Choosing a Proper Wiring Scheme

In general, there are two common wiring schemes, T568A and T568B, which are designed to specify the arrangement of the colored wires for terminating the Ethernet patch cable. That’s to say, if you want to terminate your cable, you should arrange the colored wires in a correct order according to the standard of T568A or T568B, as shown in the following figure. As for their applications, T568A is always applied in home-networking connections, while T568B is strongly suggested for the preexisting residential network wiring or other similar projects.

wiring orders of t568a and t568b

Terminating the Ethernet Patch Cable You Need

There are ten detailed steps to make the Ethernet patch cable you need at an exact length, which will be presented below. Terminating the cable you need according to the following step-by- step procedures can ensure the performance of the DIY cable and the stability of your network.

  • Prepare the essential tools and materials for the cable termination, including some RJ45 connectors, a pair of wire scissors or wire strippers, a spool of Ethernet cable, a RJ45 crimping tool and a network cable tester.
  • Use the wire scissors or wire strippers to cut the Ethernet patch cable you need into a desirable one with the exact length. Besides, you’d better to add two or three inches extra no matter how long you want the Ethernet patch cable to be, for the sake of messing up.
  • Utilize the RJ45 crimping tool to shove the sheath of the cable (about 1 inch) from the end of the cable into the stripper, and lightly squeeze the crimping tool.
  • When the razors slice of the crimping tool pass through the cable jacket, you should twist the cable and pop off the cut end of jacket.
  • Once the jacket is stripped, you can see four twisted pairs of wires with four different colors. You should separate these four pairs of wires into eight individual wires and rearrange them into sequence according to the color order in T568A or T568B.
  • Cut the tips of the wires in order to match with the RJ45 connector. Then guide the wires into the plug and slip them into their own channels. The ends of the wires should reach as far as possible toward the front edge of the plug.
  • Double check and confirm whether the wires are in sequence according to the right order or not, avoiding error connection.
  • Insert the plug into the crimping slot of the crimping tool and squeeze the crimping tool to make the pins inside the plug into the wires and fasten the plug onto the cable. Hence, the RJ45 connector can be a permanent part of the new cable.
  • As for the other end of the cable, just terminate it in the same way, so that you can finish the whole termination process for your own Ethernet patch cable.
  • Test the cable by a network cable tester to confirm that it really works. In addition, if it doesn’t work, you are highly suggested to check the color order of the wires first.

Before making your own Ethernet patch cable, you should choose a proper Ethernet patch cable and a wiring scheme according to your network requires. As for the process of making the cable with an exact length, it is not so difficult as you consider, but easy and fast. The only thing that deserves a bit of attention is to be careful in the whole termination process, so that the Ethernet patch cable can be made at a proper length and work with your network like a charm.

  Aucun commentaire | Ecrire un nouveau commentaire Posté le 29-12-2016 à 08h50

 An In-Depth Look at Mode Conditioning Patch Cable Alerter l'administrateur Recommander à un ami Lien de l'article 

As we all know, fiber optic cable jumper plays an important role in Ethernet network connection, which becomes more and more diversified to satisfy the different connection requirements in recent years. For instance, standard fiber patch cable like single mode patch cable and multimode patch cable, special fiber patch cable like mode conditioning patch cable and bend insensitive patch cable, etc. Among these various fiber patch cables, mode conditioning patch cable has been one of the most popularly used fiber patch cable due to its unique features and advantages, which will be introduced in the following text.

What Is Mode Conditioning Fiber Patch Cable?

Mode conditioning patch cable is a special kind of duplex fiber patch cable that consists of two fibers, a conditioned fiber and a non-conditioned fiber, capped at either end with connectors. In the conditioned fiber, a single mode fiber and a multimode fiber are fusion spliced in an offset manner, with a precise core alignment and angle, protected by a black over-wrap. While in the non-conditioned fiber, there is only a length of multimode fiber. To get a better understand of its structure, you can take the following figure as reference.

mode conditioning patch cable

As shown in the figure above, there are two multimode fibers in one end, and a multimode and single mode fiber in the opposite end. The end with two multimode fibers is designed to connect the cable plant, while the other end connects to the transceiver equipment with the single-mode leg linking to the transmit side. Hence, light signal can be launched on to the multimode fiber in the conditioned one at a specific angle, giving the patch cable its mode conditioning property. Besides, it is worth mentioning that this kind of fiber optic cable is fully compliant with IEEE 802.3z application standards.

Why Mode Conditioning Cable Is Used?

As far as our information goes, 1310nm long wave signal is always transmitted through single mode patch cable for 1000BASE-LX transmission as a cost effective solution. However, if the mentioned above transmission utilizes multimode patch cable, it will cause a phenomenon known as DMD (differential mode delay). In simple words, if the same signal is carried to a multimode patch cable, there will be multiple signals created in the multimode patch cable that may make transmission errors to some extent.

In order to solve this problem, mode conditioning patch cable is put forward that utilizes an offset between the single-mode fiber and multimode fiber to eliminate transmission errors, allowing for 1000BASE-LX signal transmission through multimode patch cable. For example, when 1000BASE-LX routers and switches are installed into existing multimode cable plants, mode conditioning patch cable is highly recommended to adapt the single-mode output of 1000BASE-LX transceivers to a multimode cable network.

Notices for Using Mode Conditioning Patch Cable

After knowing the feature and advantage of mode conditioning patch cable, do you also consider using mode conditioning patch cable to finish the conversion from single mode to multimode? Here are some notices for you so as to use the mode conditioning patch cable in a proper way.

    • Mode conditioning patch cable should be used in pairs to finish the conversion. That's to say, most orders for this kind of fiber optic cable are always in even numbers. If there is an odd number order, the single one must be used for standby application or replacement.

    • Mode conditioning patch cable is only able to convert single-mode transmission to multimode transmission. If the conversion from multimode to single-mode is required, you are suggested to choose a media converter as an easy and cost effective solution.

    • Please check and confirm the connector of your switch before application. If it is equipped with SC or LC connectors, you should connect the yellow leg (single-mode) of the cable to the transmit side and the orange leg (multimode) to the receive side of the equipment. It is imperative that this configuration should be maintained on both ends.


Mode conditioning patch cable enables the conversion from single-mode to multimode with the feature of fusion splicing between single mode fiber and multimode fiber. After knowing its feature and advantage, if you want to choose this kind of cable to finish the conversion in your network, you can order it from FS.COM. It is no doubt that there are various mode conditioning patch cables with different connectors available. Besides, if you cannot find one to meet you requirement, you can also order custom fiber patch cables for your network.

  Aucun commentaire | Ecrire un nouveau commentaire Posté le 22-12-2016 à 11h26

 LC Interface or MTP/MPO Interface for 40G QSFP+ Module Alerter l'administrateur Recommander à un ami Lien de l'article 

As we know, duplex LC interfaces are widely used in 10G SFP modules, for instance, SFP-10G-LR-S module and SFP-10G-SR module, which occupy the majority of 10G module market. However, for 40G QSFP+ modules, both LC interface and MTP/MPO interface play important roles in meeting the high speed transmission, which are available on 40G QSFP module market. What are the differences between these two interface types? Which one should be chosen when deploying 40G Ethernet network? Do they function similarly in the same application? Let’s talk about this topics and find one kind of 40G QSFP+ module with the most suitable interface type so as to make a smooth 40G connection for our network.

Differences Between LC Interface and MTP/MPO Interface

From the following figure, we can see the examples of QSFP+ modules with two different interfaces. The left one is the module with with LC interface, while the right one is with MTP/MPO interface. The differences between these two kinds of modules vary from the fiber types they work with to the working principles, which will be analyzed in the following text.

40G transceiver with MTP and LC interface

Different Fiber Types

As for the QSFP+ module designed with LC interface, it usually works with single mode fiber (SMF). Since SMF is able to support 40G network for a very long distance, the LC interface module is widely applied in long transmission. However, the QSFP+ module with MTP/MPO interface design is strongly recommended in the short distance application where the 40G signals are transmitted through multimode fiber (MMF). What should be paid attention to are some special QSFP+ modules, like QSFP-40G-PLRL4 and QSFP-40G-PLR4 module, which don’t fit the rule. Although the two kinds of modules mentioned above are designed with MTP/MPO interfaces, they are also capable of supporting 40G long distance transmission through SMF.

Different Working Principles

As shown in the following figure, QSFP+ module with LC interface has a very complicated working principle for transmitting 40G signals. At the beginning of the transmission, four 10G serial data signals via four channels are transmitted to laser drivers in the transmitting side. Then they are directly controlled by the laser drivers as four modulated lasers (DML) with different wavelengths. After that, the output of four DMLs are optically multiplexed as a total 40G optical signal and transmitted through the LC connector and the SMF. While in its receiving side, the 40G optical signal is demultiplexed into four individual 10G signals with different wavelengths, then collected by the discrete photo diode, and finally amplified by the TIA and outputted as electric data.

LC interface qsfp module working principle

As for QSFP+ module with MTP/MPO interface, its working principle is much easier than the previous one as it doesn’t require CWDM technology. In its working process, the transmitter firstly converts four 10G parallel electrical input signals into parallel optical signals by using the laser array. Then the four 10G parallel optical signals are directly transmitted through the MMF ribbon in a parallel mode. Finally, these parallel optical signals are transmitted through the photo detector array and converted into parallel electrical output signals in the receiving side. To better understand the working principle, here offers the figure of its detailed working process.

mtp mpo interface qsfp module working

Besides, the mentioned above QSFP+ module with MTP/MPO interface, like QSFP-40G-PLRL4 and QSFP-40G-PLR4, also works in a parallel mode that features four independent transmitting and receiving channels to finish 10G operations, achieving a whole 40G connection. The only difference of the working principle is that the signals are transmitted and received through eight SMF ribbons, hence this kind of module can also achieve a long distance transmission.


From this article, we can easily find that QSFP+ module with LC interface is more commonly used for long distance application, while QSFP+ module with MTP/MPO interface is a cost effective solution for short distance application. Except that, there is still a great difference for applications between the two kinds of modules due to their different working principle. As QSFP+ module with LC interface uses CWDM technology to transmit signals with different wavelengths through a pair of single mode fibers, the 40G signals can’t be separated into four 10G signals and transmitted to 10G devices. However, QSFP+ module with MTP/MPO interface can be used in the 40G to 10G application by using an external 12-fiber parallel to 2-fiber duplex breakout cable.

  Aucun commentaire | Ecrire un nouveau commentaire Posté le 16-12-2016 à 10h13

 How to Install 40G QSFP+ Transceiver for Your Network? Alerter l'administrateur Recommander à un ami Lien de l'article 

With the continuously growing demand for higher capacity and bandwidth, the deployment of 40G Ethernet network becomes much more necessary than ever before. As one of the key components to accomplish a whole 40G connection, QSFP+ transceiver, a compact, hot-pluggable module, is designed with four independent channels to transmit and receive 10G signals, supporting 4x10 Gbit/s data rates. This kind of module can be used both in 40G to 40G application where one QSFP+ transceiver will be connected to another QSFP+ transceiver and in 10G to 40G application where one QSFP+ transceiver will be connected to four SFP+ transceivers.

Do you also want to upgrade your system from 10G to 40G Ethernet network by using QSFP+ transceiver? The following will detailedly describe the step-by-step procedures for installing QSFP+ transceiver and attaching optical network cable to the transceiver, which will be helpful for you to achieve a fast, smooth and seamless 40G network deployment.

QSFP+ Transceiver Installation

Before installing QSFP+ transceiver, three tools should be prepared for the 40G migration. One is the wrist strap or other grounding device with the function of avoiding ESD (electro-static discharge) occurrence. Another is the antistatic mat or antistatic foam, capable of setting the transceiver on. The other is the equipment for fiber-optic end-face cleaning and inspection. All of these tools are indispensable for making a secure and smooth installation.

After that, you can start to install the QSFP+ transceiver according to the following procedures. Considering that there is either a pull-tab latch or a bail-clasp latch in QSFP+ transceiver, the procedures for both types will be listed below.

  • Put the ESD wrist strap on and attach the other end of the ESD wrist strap to a properly grounded point on the chassis or the rack.
  • Get the QSFP+ transceiver by removing its protective packaging.
  • Check the QSFP+ transceiver label and confirm whether the type of the module is suitable for your network or not.
  • Remove the optical bore dust plug from the transceiver and store it in a clean place, therefore it can be easily found and fast used next time.
  • Since there are two kinds of latches for the transceivers, they should be connected to your network in different ways. As for the transceiver with a pull-tab latch, you should hold it to ensure the identifier label is on the top. As for another transceiver, you should keep its bail-clasp aligned in a vertical position (see the following figure).
  • Then align and slide the transceiver to the module socket carefully until it contact with the socket electrical connector.
  • Press firmly on the front of the QSFP+ transceiver with your thumb to fully seat the transceiver in the module socket.
  • Reinstall the dust plug into the transceiver optical bore before attaching the optical network cable to the transceiver.
install qsfp transceiver with bail clasp latch
Optical Network Cable Attachment

After installing the QSFP+ transceiver, you should attach the optical network cable to the transceiver to finish the whole 40G transmission. But how to attach the optical network cable? What should be paid attention to in the attaching procedures? The following will talk about this topic and give you answers.

Before making the 40G connection, you should ensure that the unplugged optical network cable connectors and the transceiver optical bore are protected by the dust plugs. Meanwhile, you should also check and clean the MPO connector or duplex LC connector end faces. Besides, you can only grasp the connector housing to plug or unplug the optical network cable. Once these points are confirmed, you can attach the optical network cable to your network.

The procedures for attaching the optical network cable to the transceiver are shown below.

  • Remove the dust plugs from the optical network interface cable connectors and the QSFP+ transceiver module optical bores. Also, keep the dust plugs in a clean place.
  • Check and clean the connector end faces of the optical network interface cable.
  • Immediately attach the optical network interface cable connector to the QSFP+ transceiver.
  • Pull slightly on the cable connector boot to check whether the optical network cable is fully seated. If not, please reattach it and make it seated.

From this paper, it can be easily learned to install the 40G QSFP+ transceivers and attach the optical network cables to the QSFP+ transceivers, hence the 40G connection can be smoothly finished in a correct way. Using the methods mentioned above to upgrading your network can protect the QSFP+ transceivers from being damaged and keep a stable performance for the 40G connection.

  Aucun commentaire | Ecrire un nouveau commentaire Posté le 14-12-2016 à 10h48

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