Category: Fiber Transceivers

Optical transceivers, Active Optic Cables, data center switches, and cable management in data centers.

Can I Connect Fiber Optic Transceivers of Different Brand?

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Data centers generally accommodates hundreds or even thousands of network switches, it happens when you have to connect switches from different vendors (i.e. switch X from Cisco and switch Y from HP). As the switches only fit their own brand-based fiber optic transceiver, the main issues thus falls into this: is it possible to contact two different vendor’s fiber optic transceiver module and form a viable link? The answer is yes – but you still have to take some critical aspects into account.
connect optical transceivers from different brand
Case Study: Standard of Fiber Optic Transceiver is the Key
Sometimes people have to mix switches and fiber optic transceivers, mainly because the following reasons:
They already have brand X and they need more switches and they shop on price. Hence different brands
They need to replace switches but do not have money for all and they buy brand X and plan on going to brand X completely but it takes time to get there.
There exist quite a lot standards and protocols concerning fiber optic transceiver. Although many installers are very familiar with linking different vendor’s switch, the others are still worried that the incompatibilities of two transceivers may impede the link performance. They may come across the questions like “Can I order a 1000BASE-LX transceiver from any source and it will be compatible with all others 1000BASE-LX?” or “Would a link with a Juniper 1000Base-LX and a Cisco 1000BASE-LX transceiver work?”
fiber optic transceiver
Ideally it should work. 1000BASE-LX is a standard the same way 1000BASE-T is, except that it uses fiber as the transmission medium. You’ve already known that any copper interfaces with 1000BASE-T is interoperable since they are defined by the same 1000BASE-T standards. So you can expect the same with fiber 1000BASE-LX interfaces –  which are all defined by 1000BASE-LX. While this is true on the fiber side of the system, and should be true on the thing with the fiber optic transceiver socket. In fact, you can rest assure as SFP is multi-vendor standard that specified by a multi-source agreement (MSA). And it is a popular industry format jointly developed by many network component vendors.
Further Consideration of Fiber Optic Transceivers: Protocol, Transmission Wavelength and Cable Type
Connecting SFP optical transceivers from two different vendors still have some other restriction, since SFP transceivers differs from one another in protocol, interface type and transmission distance.
Ethernet Protocol: You have to pay attention that you use fiber optical transceiver of the same protocol at each end, for example: both sides with SX, LX or whatever is currently in use. Otherwise, you have to undertake the risk of link failure.
Cable Type: The fiber optic transceivers on each end must use the same fiber type. An SFP made for multimode fiber isn’t going to work well, if it does at all, with single-mode fiber. Same applies with other multimode fiber types: although mixing various 50 um fibers (OM2 and OM4) may work OK depending on data rate and distance. As long as each end is the same fiber type, you can mix vendors and even connector types, such as SC on one end and LC on the other end.
Wavelength: It is vital the wavelength of the fiber optic transceivers (850nm, 1310nm) matches on each end, as a 1310nm transceiver will NOT talk to a 850 nm transceiver. MMF has a lot of loss, and the wrong wavelength may cause loss and degradation on the longer runs. As for SMF, you need to be even more careful about wavelengths though, especially for long distance. So, if you are on the working range, all the fiber optic transceiver will work normally.
wavelength for optical transceiver
Conclusion
It is hence safe to say that when connecting two fiber optic transceivers from different fiber optic transceiver manufacturers, you can expect your fiber patch cable to lead a consistent link as long as you use modules of the same Ethernet protocol, cable type and working wavelength. fiber-mart provides fully compatible optical transceivers with affordable price and decent performance. For more information, please visit http://www.fiber-mart.com.

Differences Between SFP, BiDi SFP and Compact SFP

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As we know, a common SFP transceiver is generally with two ports, one is TX port which is used to transmit the signal, and the other one is RX port which is used to receive signals. Unlike common SFP transceiver, BiDi SFP transceiver is only with one port which uses an integral WDM coupler to transmit and receive signals over a single strand fiber. In fact, the compact SFP is a 2-channel BiDi SFP, which integrates two BiDi SFPs in one SFP module. Therefore, a compact SFP is also with two ports as the common SFP.
Differences Between SFP, BiDi SFP and Compact SFP
SFP, BiDi SFP and Compact SFP Connection Methods
All SFP transceivers must be used in pairs. For common SFPs, we should connect the two SFPs which have the same wavelength together. For example, we use a 850nm SFP at one end, then we must use a 850nm SFP on the other end (shown in the figure below).
common SFP
For BiDi SFP, since it transmits and receives signals with different wavelengths, we should connect the two BiDi SFPs which have the opposite wavelength together. For example, we use a 1310nm-TX/1490nm-RX BiDi SFP at one end, then we must use a 1490nm-TX/1310nm-RX BiDi SFP on the other end (shown in the figure below).
BiDi SFP
The compact SFP (GLC-2BX-D) usually uses 1490nm to transmit signal and the 1310nm to receive signal. Therefore, the compact SFP is always connected to two 1310nm-TX/1490nm-RX BiDi SFP over two single-mode fibers (shown in the figure below).
Compact SFP
BiDi SFP and Compact SFP Applications
At present, the BiDi SFP is mostly used in FTTx deployment P2P (point-to-point) connection. A FTTH/FTTB active Ethernet network consists of a central office (CO) connecting to the customer premises equipment (CPE). Active Ethernet networks use a P2P architecture in which each end customer is connected to the CO on a dedicated fiber. BiDi SFP allows a bi-directional communication on a single fiber by using wavelength multiplexing (WDM), which makes CO and CPE connection more simple. Compact SFP enormously increases CO port density by combining two single fiber transceivers into one SFP form factor. In addition, the compact SFP will significantly reduce the overall power consumption at the CO side.
Compact SFP FTTx
fiber-mart.COM BiDi and Compact SFP Sloutions
fiber-mart.COM provides a variety of BiDi SFPs. They can support different data rate and support transmission distance up to max 120 km that can meet the demands of today’s fiber services for carriers and enterprises.

Which SFP Fiber Cable Should I Choose for My Optical Transceiver?

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SFP fiber cable and fiber optic transceiver have become more and more important in fiber optic data transmission, especially in data transmission between the switches and equipment. But with so many different kinds of SFP fiber cables available in the market, which one is suitable for may optical transceiers? This article may on this issue to provide some solutions. Before starting this topic, it is necessary for us to review the basic knowledge of the fiber optic transceiver and fiber optic cable.
Fiber Optic Transceiver Overview
Fiber Optic Transceiver is a self-contained component that can both transmit and receive. Usually, it is inserted in devices such as switches, routers or network interface cards which provide one or more transceiver module slot. There are many optical transceivers types, such as SFP+ transceiver, X2 transceiver, XENPAK transceiver, XFP transceiver, SFP (Mini GBIC) transceiver, GBIC transceiver and so on.
Fiber Optic Patch Cable Overview
Fiber optic patch cable, also known as fiber jumper or fiber optic patch cord. It is composed of a fiber optic cable terminated with different connectors on the ends. Fiber optic patch cables are used in two major application areas: computer work station to outlet and patch panels or optical cross connect distribution center. According to fiber cable mode, cable structure or connector types etc., fiber patch cable can be divided into different types.
1.Single-mode and Multimode SFP fiber Cable
According cable mode, patch cables can be divided into single-mode and multimode fiber patch cable. The word mode means the transmitting mode of the fiber optic light in the fiber optic cable core. Single-mode patch cables are with 9/125 fiber glass and are yellow jacket color, while multimode patch cables are with OM1 62.5/125 or OM2 50/125 fiber glass and are orange color. In addition, there is 10G OM3 and OM4 multimode patch cables which cable jacket are usually aqua.
2.Simplex and Duplex SFP fiber Cable
Simplex fiber patch cable is consist of single fiber core, while duplex fiber patch cable is consist of two fiber cores and can be either singlemode or multimode. Additionally, there is also ribbon fan-out cable assembly (ie. one end is ribbon fiber with multi fibers and one ribbon fiber connector such as MTP connector (12 fibers), the other end is multi simplex fiber cables with connectors such as ST, SC, LC, etc.).
3.LC, SC, ST, FC, MT-RJ, E2000, MU and MPO/MTP Patch Cable
Fiber optic patch cable can be also classified by the types of fiber optic connector. For example, LC fiber optic patch cable is named as it is with LC connector. Similarly, there are SC, ST, FC, MT-RJ, E2000, MU and MPO/MTP fiber optic patch cables. What’s more, there are PC, UPC, APC type fiber patch cords, which are differentiated from the polish of fiber connectors.
Which SFP fiber Cable Should I Choose for My Fiber Optic Transceivers?
Now, I will take the Cisco fiber optic transceiver as an example to discuss this topic. For example, we need to choose a right patch cable to connect Cisco fiber optic transceiver SFP-10G-SR and X2-10GB-SR. Which patch cable to use? According to “Cisco 10-Gigabit Ethernet Transceiver Modules Compatibility Matrix”, we may know that SFP-10G-SR is the 10GBASE-SR SFP+ transceiver module for MMF, 850-nm wavelength, LC duplex connector. And X2-10GB-SR is the 10GBASE-SR X2 transceiver module for MMF, 850-nm wavelength, SC duplex connector. Obviously, this two knids of optica trancseivers are both for MMF, so we should choose a multimode patch cable. Besides, we know X2-10GB-SR is designed for SC duplex connector and the SFP-10G-SR is designed for duplex LC connector, so we should use a patch cable with SC-LC duplex connector.
The Most Common Used SFP fiber Cable Selection
In the way mentioned above, you could choose right fiber patch cable for your other transceiver modules. Keep in mind that if your transceiver modules are not Cisco’s, you need to ask your brand supplier to get the corresponding compatibility matrix. In fact, in terms of a same kind of optical transceiver, different supplier may provide the transceiver with different specifications. Here I may list the most common used patch cables selection. Hope to give you smoe reference.

Introduction of 40 Gigabit QSFP+ Transceiver

by http://www.fiber-mart.com

QSFP+ (Quad Small Form-factor Pluggable Plus) transceiver interfaces a network device motherboard (for a switch, router, media converter or similar device) to a fiber optic cable, which is widely used for data communications applications. It is a industry format jointly developed and supported by many network component vendors. QSFP+ is also the IEEE standard connector for the emerging 40GbE standard. QSFP+ modules increase the port-density by nearly 3 times when compared to SFP+ module.
Overview on 40G QSFP+ Transceiver
40G QSFP+ transceivers are designed to support Serial Attached SCSI, 40G Ethernet, 20G/40G Infiniband, and other communications standards. The 40G QSFP+ modules are favorable for high density 40G optical network. These modules are designed to operate over single-mode or multimode fiber systems with differently optimized lasers under different standards. 40G QSFP+ transceiver interface can be either duplex LC or 12-fiber MTP/MPO as shown in the following picture. The 40G QSFP+ transceiver module with MTP/MPO interface is a hot-swappable, parallel fiber-optical module with 4 independent 10 gigabit per second data lanes in each direction to provide 40Gbps aggregate bandwidth. 40G QSFP+ modules offer customers a wide variety of high-density 40 gigabit Ethernet connectivity options for data center, high-performance computing networks, enterprise core and distribution layers, and service provider transport applications.
Application of Different 40G QSFP+ Transceivers
The transceiver is used primarily in short reach applications in switches, routers, and data center equipment where it provides higher density than SFP+ modules. With the evolving of the format specification, now in the market, you can find a wide varieties of 40G QSFP+ transceivers including the short distance types, Bidi, and long distance types, of which 40GBASE-SR4 (QSFP-40G-SR4), 40GBASE-LR4 (QSFP-40G-LR4) and 40GBASE-ER4 (QSFP-40G-ER4) are the most commonly used physical layers for 40G QSFP+ modules.
QSFP-40G-SR4 (short range) transceiver has a port type for multimode fiber and uses 850nm lasers. It supports link lengths of 100 m and 150 m respectively on laser-optimized OM3 and OM4 multimode fiber cables. It is commonly used in data centers to interconnect two Ethernet switches with 12 lane ribbon OM3/OM4 cables. Primarily it enables high-bandwidth 40G optical links over ribbon fiber cables terminated with multi-fiber connectors (MTP/MPO), and could also be used along with ribbon to duplex fiber breakout cables for connectivity to four 10GBASE-SR optical interfaces.
QSFP-40G-LR4 (long range)or QSFP-40G-ER4 (extended range) transceiver has a port type for single-mode fiber and uses 1300nm region lasers. It uses two strands of fiber and combines four wavelengths by CWDM technology, delivering serialized data at a rate of 10Gbit/s per wavelength. Thus the optical interface can be simplified to standard LC connectors. QSFP-40G-LR4 transceiver is most commonly deployed between data canters or for IXP (Internet exchange point) site.
Conclusion
The QSFP+ transceiver is a great solution for multi-lane data communication and interconnect applications. fiber-mart.COM offers the best 40G QSFP+ modules. All these 40G QSFP+ modules are Cisco, Juniper, IBM and HP compatible. In addition to 40Gbps Ethernet interconnects, it can be used in datacom/telecom switch, and router connections, as well as data aggregation and backplane applications. Also you can have a wide selection of other transceivers and direct attached cables at fiber-mart.COM, including XFP transceivers, SFP transceivers, CFP modules, copper DAC, active optical cable and so on.

How to choose the right Single-mode Fiber?

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As we all know, multimode fiber is usually divided into OM1, OM2, OM3 and OM4. Then how about single-mode fiber? In fact, the types of single-mode fiber seem much more complex than multimode fiber. There are two primary sources of specification of single-mode optical fiber. One is the ITU-T G.65x series, and the other is IEC 60793-2-50 (published as BS EN 60793-2-50). Rather than refer to both ITU-T and IEC terminology, I’ll only stick to the simpler ITU-T G.65x in this article. There are 19 different single-mode optical fiber specifications defined by the ITU-T.
Each type has its own area of application and the evolution of these optical fiber specifications reflects the evolution of transmission system technology from the earliest installation of single-mode optical fiber through to the present day. Choosing the right one for your project can be vital in terms of performance, cost, reliability and safety. In this post, I may explain a bit more about the differences between the specifications of the G.65x series of single-mode optical fiber families. Hope to help you make the right decision.
G.652
EThe ITU-T G.652 fiber is also known as standard SMF (single-mode fiber) and is the most commonly deployed fiber. It comes in four variants (A, B, C, D). A and B have a water peak. C and D eliminate the water peak for full spectrum operation. The G.652.A and G.652.B fibers are designed to have a zero-dispersion wavelength near 1310 nm, therefore they are optimized for operation in the 1310-nm band. They can also operate in the 1550-nm band, but it is not optimized for this region due to the high dispersion. These optical fibers are usually used within LAN, MAN and access network systems. The more recent variants (G.652.C and G.652.D) feature a reduced water peak that allows them to be used in the wavelength region between 1310 nm and 1550 nm supporting Coarse Wavelength Division Multiplexed (CWDM) transmission.
G.653
G.653 fiber was developed to address this conflict between best bandwidth at one wavelength and lowest loss at another. It uses a more complex structure in the core region and a very small core area, and the wavelength of zero chromatic dispersion was shifted up to 1550 nm to coincide with the lowest losses in the fiber. Therefore, G.653 fiber is also called dispersion-shifted fiber (DSF). G.653 has a reduced core size, which is optimized for long-haul single-mode transmission systems using erbium-doped fiber amplifiers (EDFA). However, its high power concentration in the fiber core may generate nonlinear effects. One of the most troublesome, four-wave mixing (FWM), occurs in a Dense Wavelength Division Multiplexed (CWDM) system with zero chromatic dispersion, causing unacceptable crosstalk and interference between channels.
G.654
The G.654 specifications entitled “characteristics of a cut-off shifted single-mode optical fiber and cable.” It uses a larger core size made from pure silica to achieve the same long-haul performance with low attenuation in the 1550-nm band. It usually also has high chromatic dispersion at 1550 nm, but is not designed to operate at 1310 nm at all. G.654 fiber can handle higher power levels between 1500 nm and 1600 nm, which is mainly designed for extended long-haul undersea applications.
G.655
G.655 is known as non-zero dispersion-shifted fiber (NZDSF). It has a small, controlled amount of chromatic dispersion in the C-band (1530-1560 nm), where amplifiers work best, and has a larger core area than G.653 fiber. NZDSF fiber overcomes problems associated with four-wave mixing and other nonlinear effects by moving the zero-dispersion wavelength outside the 1550-nm operating window. There are two types of NZDSF, known as (-D)NZDSF and (+D)NZDSF. They have respectively a negative and positive slope versus wavelength. Following picture depicts the dispersion properties of the four main single-mode fiber types. The typical chromatic dispersion of a G.652 compliant fiber is 17ps/nm/km. G.655 fibers were mainly used to support long-haul systems that use DWDM transmission.
G.656
As well as fibers that work well across a range of wavelengths, some are designed to work best at specific wavelengths. This is the G.656, which is also called Medium Dispersion Fiber (MDF). It is designed for local access and long haul fiber that performs well at 1460 nm and 1625 nm. This kind of fiber was developed to support long-haul systems that use CWDM and DWDM transmission over the specified wavelength range. And at the same time, it allow the easier deployment of CWDM in metropolitan areas, and increase the capacity of fiber in DWDM systems.
G.657
From the passage above, we know that different kind of single-mode fiber has different application. Since G.657 is compatible with the G.652, some planners and installers are usually likely to come across them. In fact, G657 has a larger bend radius than G.652, which is especially suitable for FTTH applications. And due to problems of G.643 being used in WDM system, it is now rarely deployed, being superseded by G.655. G.654 is mainly used in subsea application. According to this passage, I hope you have a clear understanding about these single-mode fibers, which may help you make the right decision.

The way to choose Suitable Copper Patch Panel?

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In the data center, copper patch panel is an ideal method to create a flexible, reliable and tidy cabling system. Today, various types copper patch panels can be found in the market, such as shielded or unshielded, flat or angled, etc. So how to select the most suitable one for your applications? This article will guide you to make the right decision.
What Is Copper Patch Panel?
A copper patch panel is used in a local area network (LAN) as a mounted hardware assembly that contains ports to connect and manage incoming and outgoing Ethernet cables. The patch panels apply copper patch cords to create interconnection. Copper patch panels are designed for both shielded and unshielded copper cables like Cat 5e, Cat 6, Cat 6a and Cat7. And the configurations can be different from numbers of ports, such as 12-port, 24-port, 48-port, 96-port.
Copper Patch Panel Types
Shielded vs. Unshielded
There are shielded and unshielded copper cables. Thus, shielded and unshielded patch panels are required to match with cable applications. However, some may forget to consider this factor before buying a suitable patch panel. So you may wonder if it’s ok to use shielded cable with an unshielded patch panel.
It’s known that shielded patch panels are designed for high EMI (Electro Magnetic Interference) environments, where interference is a risk. These patch panels can protect your high speed network from noise and EMI especially when the copper cables run near power cables.
Whether you can use unshielded patch panel for shielded cable, it depends on the environment in which your cable will run through. If the place has no high power electrical wires, you can go with unshielded patch panel. However, if you are in a noisy environment like using arc welders or near high power radio transmitters, then you should better select shielded. One more suggestion is that you may also consider the network speed. Both shielded and unshielded are ok for 1G while only shielded is proper for 10G network.
Flat vs. Angled
Copper patch panels include flat and angled types from appearance design. Flat patch panels help horizontal cable managers to organize and route cables into vertical managers. Angled patch panels are easy for cable termination and can improve patch cord routing. They serve as alternatives for management that need no rack space for horizontal management. The angled design increases rack density, managing high-density applications in one-fourth the area needed for conventional cable management systems. But angled panels are not good for cabinet installation due to the front depth requirements.
Common vs. High Density
Common patch panels are always designed in 8 or 12-port configurations. While high density patch panels are available in flat and angled designs with 24 or 48 ports configurations. High density patch panel is suitable for installations with limited space. It’s a good choice for small home and office networks. High-density patch panel is specially designed for fast Ethernet applications and conserves rack space. So space is the first factor to be considered for making the decision between common and high density patch panels.
Since there are so many types of copper patch panels in the market, choosing a suitable one is necessary for easy cable management. The above content has given a brief introduction of several common types. Hope it can help you make a choice when you prepare to buy patch panels.