SFP+ compatibility issues? Here are 5 troubleshooting tips!

by Fiber-MART.COM

Have you ever tried to plug an optic SFP+ transceiver into an SFP+ port to discover that the connection didn’t work, i.e. traffic was very slow or there was no data transmission at all? Did you manage to diagnose the problem and find a resolution? There are several possible reasons for failure. We’ve listed the five most common ones.

 

sfp_plus

First of all, let’s briefly recap what SFP and SFP+ stand for. SFPs – short for ‘small form-factor pluggable’ – are compact, hot-pluggable devices that link networking devices, like switches, routers and servers. In this article, we focus on optic transceivers, as they’re called, which deliver 1Gbps of data across single-mode or multi-mode fibers. The SFP+ is an enhanced version of the SFP that supports data rates up to 10 Gbps. Now, the difference between SFP and SFP+ is an important one when troubleshooting: the transceivers are not always interchangeable.

 

TIP 1: Check whether you’re using SFP or SFP+ transceivers and slots

SFP and SFP+ modules look exactly the same. And as they have the same size, your SFP transceiver will fit seamlessly into an SFP+ switch port and vice versa. However, the connection won’t work as you expect it to. Or, worse even, it won’t work at all. If you plug an SFP device into an SFP+ port, the speed will be locked at 1 Gbps. Plugging an SFP+ module into an SFP port delivers no results at all, as the 10G transceiver can never auto-negotiate to 1Gbps.

 

TIP 2: Ensure that the SFPs have identical wavelengths at both ends 

Data transmission implies that data is sent from one end to another. The SFP+ transceiver on one end converts electrical signals into optical signals . A built-in laser transmits light through the fiber to the other side. Here, an optical diode converts the light back into an electrical signal. To guarantee that the SFP+ at the other end is capable of doing this, the SFPs at both ends should support the same wavelength. An 1310nm transceiver, for example, will not talk to an 850 nm transceiver.

 

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→ Here, too, look at the specs on the sticker of the modules or check out the details on the manufacturer’s website. Don’t look into the laser light ! Use your smartphone camera if you want to verify that light is coming out of the cable.

 

TIP 3: Use the correct single or multi-mode fiber cable 

Still in trouble even though you are sure you did not mix up SFP and SFP+ and are supporting the same wavelengths at both sides? If so, then verify if the optical transceivers on each end use the same fiber type, i.e. for single-mode or multi-mode fiber. And use the corresponding fiber cable.

 

Single-Mode Fiber (SMF): featuring a narrow core (typically around 9μm), SMF allows only a single mode (or “ray”) of light to propagate. It is mostly used to transmit data over long distances (max 2km – 120km).

Multi-Mode Fiber (MMF): as MMF has a much wider core (typically 50μm or 62.5μm), it allows multiple modes of light to propagate. The common MMFs are used for short distance transmissions (max 100m – 500m)

The type of fiber can be identified by use of standardized colors on the outer jacket:

 

fiber_type

TIP 4: Are both ports compatible with your SFP+ modules?

Even when using compatible SFP+s at both ends of the right cable, it is key that both of your devices support SFP+. Make sure that the SFP+ ports on your devices are compatible with the SFP+ modules you want to use. Some brands allow you to use only their own modules.

 

TIP 5: Is your optic cable in good shape?

Fiber optic cables are exceptionally vulnerable. Dust, dirt or tampering might cause physical damage. So, if you’re experiencing problems when connecting devices, check the connector, the module, and the module slot to make sure they’re not damaged.

 

To avoid physical damage, avoid extreme bends in fiber optic cables when storing them and put dust-caps on your cable ends if you disconnect them.

 

In summary, make sure that you know what you are doing when plugging in SFP+ modules and fiber optic cables! It may look simple, but transceivers and slots are not always compatible. Always check the specs on the sticker of your transceiver/the slot, or verify the details on the manufacturer’s website. Only when done right, using fiber optic cables that are in good shape, will you be able to transmit data at the desired speed!

 

5 reasons IT Pros Choose Fiber Optic Cables

by Fiber-MART.COM

When assessing which type of network cable you want to install, which type should you go with? 

 

Copper has some advantages, including the fact that it already exists in many places and is less expensive to connect network devices. While fiber optic cables are more expensive, there are several advantages that make it a more enticing cable infrastructure solution than its copper counterpart.

 

5 reasons IT Pros Choose Fiber Optic Cables

 

1. Fiber optic transmission is faster.

 

Fiber optic versus copper wire transmission can be boiled down to the speed of photons versus the speed of electrons. While fiber optic cables don’t travel at the speed of light, they come very close—only about 31 percent slower.

 

 

2. Fiber optic transmission results in less attenuation.

 

When traveling over a long distance, fiber optic cables experience less signal loss than copper cabling. This is called low attenuation. Copper cables can only transmit information up to 9,328 ft due to power loss, whereas fiber cables can travel between 984.2 ft to 24.8 miles.

 

 

3. Fiber optic cables are impervious to electromagnetic interference (EMI).

 

Copper wires, if not properly installed, will produce electromagnetic currents that can interfere with other wires and wreak havoc on a network. Fiber optic cables, unlike copper cables, do not conduct electricity.

 

 

4. Light cannot catch on fire.

 

An added benefit of fiber optic cables is that they are not a fire hazard. This can also be attributed to the same reason that the cables do not produce EMI—there is no electric current traveling through the core.

 

 

5. Fiber optic cables do not break as easily.

 

This means that you will not have to worry about replacing them as frequently as copper wires. Even though the fiber is made of glass, copper wires are more prone to damage than fiber optic cables are.

 

The Takeaway

 

So, there you have it - five good reasons why people choose fiber cables over copper cables. One could argue that many of the advantages of using fiber cables can lead to a greater ROI. Keep this in mind when deciding whether to choose copper or fiber cabling.

 

 

Want to learn more about the importance of fiber cabling infrastructures? Download the free white paper, Specifying Fiber Infrastructure as a Critical Network Component, here.

How does a fiber optic cable work?

by Fiber-MART.COM

Over the last 20 years or so, fiber optic lines have taken over and transformed the long distance telephone industry. Optical fibers are also a huge part of making the Internet available around the world. When fiber replaces copper for long distance calls and Internet traffic, it dramatically lowers costs.

 

To understand how a fiber optic cable works, imagine an immensely long drinking straw or flexible plastic pipe. For example, imagine a pipe that is several miles long. Now imagine that the inside surface of the pipe has been coated with a perfect mirror. Now imagine that you are looking into one end of the pipe. Several miles away at the other end, a friend turns on a flashlight and shines it into the pipe. Because the interior of the pipe is a perfect mirror, the flashlight's light will reflect off the sides of the pipe (even though the pipe may curve and twist) and you will see it at the other end. If your friend were to turn the flashlight on and off in a morse code fashion, your friend could communicate with you through the pipe. That is the essence of a fiber optic cable.

 

Making a cable out of a mirrored tube would work, but it would be bulky and it would also be hard to coat the interior of the tube with a perfect mirror. A real fiber optic cable is therefore made out of glass. The glass is incredibly pure so that, even though it is several miles long, light can still make it through (imagine glass so transparent that a window several miles thick still looks clear). The glass is drawn into a very thin strand, with a thickness comparable to that of a human hair. The glass strand is then coated in two layers of plastic.

 

By coating the glass in plastic, you get the equivalent of a mirror around the glass strand. This mirror creates total internal reflection, just like a perfect mirror coating on the inside of a tube does. You can experience this sort of reflection with a flashlight and a window in a dark room. If you direct the flashlight through the window at a 90 degree angle, it passes straight through the glass. However, if you shine the flashlight at a very shallow angle (nearly parallel to the glass), the glass will act as a mirror and you will see the beam reflect off the window and hit the wall inside the room. Light traveling through the fiber bounces at shallow angles like this and stays completely within the fiber.

 

To send telephone conversations through a fiber optic cable, analog voice signals are translated into digital signals (see How analog and digital recording works for details). A laser at one end of the pipe switches on and off to send each bit. Modern fiber systems with a single laser can transmit billions of bits per second -- the laser can turn on and off several billions of times per second. The newest systems use multiple lasers with different colors to fit multiple signals into the same fiber.

 

Modern fiber optic cables can carry a signal quite a distance -- perhaps 60 miles (100 km). On a long distance line, there is an equipment hut every 40 to 60 miles. The hut contains equipment that picks up and retransmits the signal down the next segment at full strength.

Everything You Need to Know Before Buying CWDM and DWDM SFP+ Transceivers

by Fiber-MART.COM

It is known to us that WDM (Wavelength-division Multiplexing) can increase network bandwidth by allowing data streams at different frequencies to be sent over a single optical fiber. With the advent of this technology, different wavelengths can be assigned to optical modules like CWDM SFP+ transceiver and DWDM SFP+ transceiver, thus expanding and optimizing the network capacity. This post aims to be a buyer’s guide of CWDM and DWDM 10G SFP+ module selection.

 

CWDM and DWDM SFP+ Transceiver Basics

Both CWDM SFP+ and DWDM SFP+ transceivers are based on the popular SFP form factor. They are commonly used in 10G Ethernet and all can reach a maximum speed of 11.25G. However, they are different in such aspects as wavelength, distance, and application.

 

10G CWDM SFP+ transceiver often operates at a nominal wavelength of CWDM wavelength. To be specific, CWDM SFP+ transceiver can support 18 wavelengths from 1270nm to 1610nm, and its transmission distance is from 20km to 80km. It is an important part in CWDM system. To learn more details about 10G CWDM SFP+ transceivers in CWDM system, you may read: How to Install Your CWDM MUX/DEMUX System

 

10G DWDM SFP+ transceiver operates at nominal DWDM wavelengths from CH17-CH61, supporting a transmission distance up to 80km. It is specifically designed for carriers and large enterprises that require a scalable, flexible, cost-effective system for multiplexing, transporting and protecting high-speed data, storage, voice and video applications. Since the wavelengths for DWDM network is boarder, 10G tunable DWDM SFP+ transceiver is also available in DWDM system, which can change the channel according to actual needs.

 

How to Select and Buy CWDM and DWDM SFP+ Transceiver on the Market

CWDM SFP+ or DWDM SFP+

CWDM SFP+ can typically support up to 18 channels, while DWDM SFP+ can support more than 40 channels on one strand of fiber. Although customers can gain more capacity and longer link distance from the DWDM SFP+, they have to pay more since cost of it is more expensive than CWDM SFP+. For customers that don’t require a long transmission distance, CWDM SFP+ may be the first choice. But in the long-term, DWDM SFP+ serves the future trend for high-density network better.

 

CWDM and DWDM SFP+ Transceiver Price

Compared with normal SFP+ modules, CWDM and DWDM SFP+ are more expensive due to the cost brought by different working modes. And as it has been mentioned before, CWDM SFP+ tends to be cheaper than DWDM SFP+. And generally speaking, the longer the supported transmission range is, the more expensive it would be for CWDM or DWDM transceivers. Also, transceivers from a third-party CWDM and DWDM SFP factory are much cheaper than the original manufacturers. Therefore, to purchase compatible modules can help you save a large sum of money.

 

CWDM and DWDM SFP+ Transceiver Supplier

As mentioned above, affordable transceivers can bring you a big save, but you need to pay attention to the reliability. Although the price for compatible modules is nice, not all of them on the market are qualified. If you don’t want to go “buy cheap, buy twice”, you need a reliable supplier. Reputed third-party suppliers like fiber-mart.COM have their own test labs to ensure the compatibility and quality of the transceiver. Customers can also enjoy after sale service and warranty from these trustworthy CWDM SFP+ suppliers.

 

Common Questions When Buying and Using CWDM and DWDM SFP+ transceivers?

1. How About the Price of CWDM SFP+ Transceiver and DWDM SFP+ Transceivers?

 

Generally speaking, the branded CWDM and DWDM transceivers are much expensive than compatible ones. Here we take Cisco CWDM-SFP10G-1470 and Cisco DWDM-SFP10G-61.41 for example. The prices for the original ones are $1500 and $2,345, while CWDM SFP10G 1470 from fiber-mart.COM only takes $360 and $369 respectively.

 

2. Do Cisco Switches Have to Be Used with Original Cisco CWDM SFP+?

 

No. There are many compatible transceivers provided by third party transceiver supplier that you can adopt to replace Cisco CWDM SFP+ or even Cisco DWDM SFP+. If you can get your transceivers from a reliable third-party supplier, they will be just as dependable as the Cisco branded ones, but for a fraction of the price.

 

3.Is It Possible to Convert the Conventional Wavelength like 850nm into DWDM or CWDM Wavelength?

 

Yes. If you need to convert the wavelengths into CWDM or DWDM wavelengths, you can employ an OEO converter to make this happen. OEO converter realizes wavelength conversion based on the O-E-O transformation technology.

 

4. How to Choose Between 100GHz and 50GHz in DWDM Channel Spacing?

 

Compared with 50GHz, the 100GHz C-Band is the commonly used in the telecom industry. The spacing between the channels is 0.8nm and it’s around 1550nm. The colors or wavelength are named in channels and channel 17 to 61 is commonly used. The 50GHz with 0.4nm spacing and other spectrum bands can be provided by most manufacturers as well.

 

5. How to Select the Suitable Fiber Cables for CWDM and DWDM SFP+ Transceivers?

 

Fiber optic cables can be categorized into two types: single-mode and multimode fiber optic cables. The former is normally used for long-distance transmission while the latter for short-distance transmission. For CWDM and DWDM SFP+ transceiver, which can support a link up to 80km, we choose single-mode fiber cables terminated with LC connector.

 

6. Is There a Difference Among CWDM and DWDM Wavelengths for Transmission Quality? Which Wavelengths Are Better?

 

Yes. Different wavelength may deliver different transmission quality. Generally speaking, 1470nm and 1550nm are the most widely used wavelength, with 1550nm being more popular since the attenuation of 1550nm is lesser and ensures better transmission quality in long-distance application.

 

Buy CWDM and DWDM SFP+ Transceivers With Less Money and Fewer Worries

As it has been mentioned before, to purchase compatible transceivers from a reliable source can be a real money-saver. The following table displays the information of compatible CWDM and DWDM SFP+ Transceivers from fiber-mart.COM.

 

Also, fiber-mart.COM provides customized services, including SFP vendor name, interface type, distance, wavelength, DDM/DOM, temperature, label, label design, and shipping package. If you need customized service or you’re unsure of which type you need, you can contact fiber-mart.COM and they will help you.

 

As a leading supplier for optical products, fiber-mart.COM can provide all the equipment you need for building a CWDM or DWDM network. And all these products are assured with a warranty and return policy.

Name Brands vs Third-Party Transceivers: Which Do You Prefer?

by Fiber-MART.COM

You may have a name brand network switch or a name brand router, but it doesn’t mean that you need to pay an expensive cost on name brand transceivers. Though many people still get confused on “third-party transceivers”, there is no doubt that the emergence of third-party transceivers really offers a more cost-effective option to users. Name brands or third-party, which do you prefer? After reading this paper, you can make a decision.

 

What Does “Third-Party” Mean?

First of all, you should know that third-party suppliers exist in all sorts of industries and are typically companies that have a high degree of specialization in their field. “Third party” as a concept comes up most often in technical areas.

 

For example, software developers create programs that can be used on platforms created by another company, and often do so to fill a niche users may need but the platform developer cannot or will not address. A quick look at that description will also give you the basis for the term “third party”. It’s not the platform or OEM (original equipment manufacturers) (first party), or the user (second party), but another (third party) developer that brings a solution to the marketplace. Seems simple enough, right?

 

Some of the confusion arises in the telecom/datacom industry, where there are OEMs that really aren’t manufacturing anything. But rather, these OEMs have things built for them under contract by ODMs (original design manufacturers), and then “integrate” this solution under their own brand name. Then there are OEMs who continue to supply components to other OEMs, while establishing a brand of their own. They can also be considered third party for other OEMs, if they’ve not explicitly been brought into the fold as a vendor to that OEM. It is not quite so simple anymore when “third-party” are introduced to telecom / datacom industry. Thus, many users feel strange to third-party components, and are lack of confidence in them.

 

Name Brands vs Third Party Transceivers

If you still don’t understand what third-party means, now let us come back to our familiar environment, talking about the transceivers. All fiber optic transceivers have established Multi-Source Agreements (MSAs). These MSAs clearly define how fiber optic networking equipment is to function and establish de facto manufacturing standards that ensure networking components developed by different manufacturers are interoperable.

 

As long as a manufacturer complies to MSA guidelines, their transceiver modules will function and operate identically to any other manufacturer’s MSA-compliant transceivers. For example, fiber-mart’s 100% MSA compliant GLC-SX-MM transceiver will function identically to a Cisco brand GLC-SX-MM transceiver and will be 100% compatible with Cisco networking equipment.

 

So, how about the name brand transceiver? Why do they cost so much? Actually, the switch and router manufacturers do not build their own transceivers. Also take Cisco for example, they resell someone else’s. As described above, they have them built under contract by ODMs. The reason why Cisco transceivers are more expensive is because they have actually tested the transceivers they offer with their equipment to verify it works. Also they have revision control over the transceivers they sell so that if something were to change on the transceiver it would trigger them to retest it. Moreover, Cisco isn’t in the business of giving stuff away, so they mark up the price of the transceivers to cover their costs (to test/procure/stock etc.) and make a profit. In addition, many name brand vendors outsource the manufacturing of their OEM components to the exact same contract manufacturers used by third party vendors. So the source, quality, parts, and programming are exactly the same—only the labels and cost to the consumer are different.

 

Many users give their feedback on third-party transceivers. They say their third-party cannot work well one their name brand switch. Why? Switch and router manufacturers such as Cisco, HP ect. have set the encryption key which forbid the third-party transceivers to plug in their device. Thus, when you plug a third-party transceiver into the device, you’ll quickly stumble across an error warning. In fact, this is not a problem, because some hidden commands or 100% compatibility technology developed by some vendors can solve this problem.

 

Third Party Transceivers: An Ideal Solution

In fact, in addition to the low cost, there are many benefits of third-party transceivers. The following five obvious and proven reasons tell you why third-party transceivers are an ideal solution for your project.

 

Cost savings

Typically third-party transceivers cost substantially less than—sometimes up to 90 percent less — already discounted transceivers from OEM providers.

 

In-stock Availability

Since selling transceivers is the primary business for most third-party transceiver companies, most strive for immediate availability of product.

 

Carrier-Grade Quality

Some companies use the exact same ODMs the major switch OEMs use. However, since optical transceivers are the primary business for some third-party transceiver companies, they may understand which ODMs provide the highest quality part for a given data rate or transport protocol. It is not inconceivable for some third-party optics companies to provide more reliable components than those offered by the major switch OEM companies.

Reduced Inventory Cost Due To Interoperability

By definition third-party providers of optical transceivers are not tied to a specific switch or router platform. Therefore, their optics will typically interoperate across multiple platforms. This means one specific inventoried part number can be used in both a Cisco switch and a Juniper switch, as an example. Thus, this approach effectively reduces sparing inventory as well as the operational headaches associated with maintaining inventories for each switch platform.

Access to Innovative Optics

Third-party providers tend to have a much broader variety of pluggable optics from which to select. This can range from 10G Ethernet single fiber SFP+ or XFP optics to 120km XFP optics, as an example.

 

 

fiber-mart offers a variety of fiber optic transceivers at very economical prices which can satisfy your requirements from 1G to 100G Ethernet. In addition, we have a large inventory of the commonly used SFP optics, fixed-channel DWDM SFP+ optics, and whole seires of 40GBASE QSFP+ optics. So, why pay more for a name, when you can get the same high-quality, MSA compliant, 100% OEM compatible and in-stock transceivers from fiber-mart for a fraction of the cost?