2018-05-22

An Introduction to SDI Video SFP: Definition, Types, Applications

Video optical transceivers are primitively used in radio and television industry. It mainly includes two series: video SFP module or video SFP+ transceiver. Then today’s topic will be involved in types and applications of SDI video SFP optical transceiver in this post.

The Definition of SDI Video SFP
SDI SFP optical module and its related products are initially designed for the radio and television industry, applied for television studio, animal filming, film shooting, large sports events live. It is extended to the 1080 PHD monitoring field. SDI SFP optical module is usually used on the SDI interface of the HD-SDI terminal device. The transmission rate and frequency for each different SDI interface are different.

Types of SDI SFP Optical Transceiver
SDI Video SFP transceivers can be divided into various types according to different factors. For example, on the basis of operating wavelength, they can be divided into 1310nm, 1490nm, 1550nm and CWDM wavelengths video SFP transceivers; based on transmission distance, there are 300m, 2km, 10km, 20km, 40km; based on operating rate, there are usually 3G-SDI, 6G-SDI and 12G-SDI video SFP optical transceivers.

3G-SDI video SFP optical transceivers have a data rate up to 3Gbps, which are specifically designed for high performance in the presence of SDI pathological patterns for SMPTE 259M, SMPTE 344M, SMPTE 292M and SMPTE 424M serial rates. They are generally used for television broadcasting. However, as technology advances, they are now also widely applied in global security applications such as high-end surveillance or unmanned systems, allowing simple designs or upgrades with full HD cameras.

6G-SDI video SFP optical transceivers’ data rate is intended to be twice as fast as 3G-SDI optical modules, which means it is supposed to deliver a payload of 6Gbps. Therefore, they are not only designed for SDI pathological patterns for SMPTE 259M, SMPTE 344M, SMPTE 292M and SMPTE 424M serial rates but also for SMPTE 2081. 6G-SDI video SFP optical transceivers are often used in camera, video, security monitoring applications and 4K /HDTV/SDTV service interfaces.

Speed up to 12Gbps, 12G-SDI video SFP transceivers are specifically designed for high performance in the presence of SDI pathological patterns for SMPTE 259M, SMPTE 344M, SMPTE 292M, SMPTE 424M, ST2081 and ST-2082 serial rates. They are mainly used for SMPTE ST-297-2006, ST-2081 and ST-2082 compatible electrical-to-optical interfaces and UHDTV/HDTV/SDTV service interfaces.

Applications of SDI SFP Optical Transceiver
1. Applied in HD Camera or Monitor System
There are usually multiple HD end-devices in HD camera or monitor system. Therefore, one HD video matrix can be used as one end which provides multiple video SFP ports, and multiple HD-SDI equipments can be used as the other ends. 3G-SDI SFP transceiver is plugged into the equipment respectively, then SDI SFP transceivers on both ends are connected via fiber optic cables.

2. Applied for Broadcast Video Transmission
Broadcast video transmission needs high-density cabling. Thus, HD-SDI equipment with high-density video SFP ports is needed.


In Conclusion
Above all is about the introduction to types and applications of video SFP module, hoping this article can be helpful to those who want to know more about video SFP transceiver. In addition, for above-mentioned two series of video optical transceivers, Gigalight currently has these types: 3G-SDI SFP, 6G-SDI SFP+, 12G-SDI SFP+. For more details, pls visit Gigalight official website.


About Gigalight:
Gigalight is a design innovator in global optical interconnect field. A series of optical interconnect products include: optical transceivers, passive optical components, active optical cables, GIGAC MTP/MPO cabling, cloud programmers & checkers, etc. Three applications are mainly covered: Data Center & Cloud Computing, MAN & Broadcast Video, and Mobile Network & 5G Optical Transmission. Gigalight takes advantage of its exclusive design to provide clients with one-stop optical network devices and cost-effective products.

2018-05-15

What Are the Differences Between QSFP28 4WDM and QSFP28 CWDM4 Optics?

Both 4WDM and CWDM4 belong to 100G QSFP28 series optical transceiver, and are certainly related to WDM (wavelength division multiplexing)tech. Maybe there are still people confused of what differences between QSFP28 4WDM and QSFP28 CWDM4 optical transceiver are. Then in this article, a comparison between them will be made by Gigalight.

An Introduction to QSFP28 4WDM Optical Transceiver
4WDM(4-Wavelength Wavelength Division Multiplexing) optical module is defined by 4WDM MSA, targeted for longer reaches, lower costs, and lower power consumption, smaller form factor(QSFP28 form factor is usually preferred). 100G QSFP28 4WDM optics have three specifications including 100G QSFP28 4WDM-10, 100G QSFP28 4WDM-20, 100G QSFP28 4WDM-40. QSFP28 4WDM-10 is one type of 100G (4x25G) optical transceivers for the 10 km based on the CWDM4 wavelength grid; QSFP28 4WDM-20 and QSFP28 4WDM-40 are types of 100G (4x25G) optical transceivers respectively for 20kms and 40kms based on the LAN-WDM wavelength grid over duplex single-mode fiber (SMF). With respect to the benefits of 4WDM, its main advantages are lower in cost and power dissipation, and longer in transmission distance.

An Introduction to QSFP28 CWDM4 Optical Transceiver
The QSFP28 100G CWDM4 optical transceiver is a full duplex, photonic-integrated optical transceiver module that provides a high-speed link with a maximum transmission distance of 2km for 100G Ethernet. 100G QSFP CWDM4 is designed for optical communication applications compliant with the QSFP MSA, CWDM4 MSA and portions of IEEE P802.3bm standard. CWDM4 interfaces with LC duplex connectors. It converts 4 input channels of 25Gb/s electrical data to 4 channels of CWDM optical signals and then multiplexes them into a single channel for 100Gb/s optical transmission. Specifically speaking, four lanes with center wavelengths of 1270nm, 1290nm, 1310nm and 1330nm are controlled on the transmitting end. On the receiving end, four lanes of optical data streams are optically de-multiplexed by an integrated optical demultiplexer. With an optical multiplexer and de-multiplexer, one just uses a duplex single-mode fiber to connect two CWDM4 QSFP28 optical transceivers.

QSFP28 4WDM vs. QSFP28 CWDM4: What Are the Differences?
QSFP28 100G CWDM4 and QSFP28 4WDM are defined with different distances(respectively are 2km/10km/20km/40km) and wavelengths(respectively are CWDM wavelength and LAN WDM wavelength). 2km and 10km use CWDM wavelength. 20km and 40km use LAN WDM wavelength.

4WDM 40km  vs. CWDM4

With the different size of the CWDM and LAN WDM wavelengths, the wavelength-transmitting TOSA for LAN WDM must be carried with a TEC (Thermo Electric Cooler). As the stable wavelength drifts with temperature, TEC consumes an extra 0.5W of power, so the overall power consumption of optical transceivers with LAN WDM wavelengths will be higher than that of CWDM optical transceivers. More differences between 100G QSFP28 CWDM4 and 100G QSFP28 4WDM are as follows:




By above comparison of QSFP28 CWDM4 and QSFP28 4WDM optical transceiver, the difference between them are very apparent. For QSFP28 4WDM series optical module, Gigalight has currently pushed out 100G QSFP 4WDM-40 and 100G QSFP 4WDM-20 optical transceiver module, but the 100GE 4WDM-40 QSFP28 optics is the key one for promotion at present. If you want to know more information about the products, pls visit Gigalight official website(www.gigalight.com).

2018-05-08

About QSFP28 PSM4 Optics: Do You Know These?

Although there have been 200G/400G optical transceiver products appearing in the optical communication market, and it does not mean that the era of 100G optical transceiver module has come to end. Actually, there still are various 100G QSFP28 optical module in great favour, such as 100G QSFP28 PSM4 and 100G QSFP28 CWDM4 optical transceiver, which meet users’ requirements for transmission distance and costs well. Then today let’s talk about the QSFP28 PSM4 optical transceiver in this post(QSFP28 CWDM4 optics has been talked about in the last post).

What Is 100G QSFP28 PSM4 Optical Transceiver?
PSM4, the abbreviation of Parallel Single Mode 4-channels, a optics with parallel technology, defined by the 100G PSM4 MSA(Multi-Source Agreement). It uses four lanes of parallel single fiber to deliever serialized data at a rate of 25Gbps per lane. 100GE PSM4 QSFP28 will be the optical transceiver that enables single-mode fiber to become popular in next-generation data centers due to its low cost and high configurability. It doesn’t need a MUX/DEMUX for each laser but it does need a directly modulated DFB laser (DML) or an external modulator for each fiber. QSFP28 100G PSM4 uses eight fibers, in which four fibers are for transmitting and four fibers are for receiving. A PSM4 QSFP28 optical module supports link lengths of up to 500 meters over single-mode fiber with 12 fiber MTP/MPO connectors. The light source of QSFP 100G PSM4 optic module is a single uncooled distributed feedback (DFB) laser operating at 1310nm.  

qsfp28 psm4 optics


Why Is 100G QSFP28 PSM4 Optical Transceiver In Demand?
It is known that the most basic 100G interfaces currently used are 100GBASE-SR4 and 100GBASE-LR4 which are defined by IEEE. However, there exists a problem between them that reaches are either too short for practical application in data center or too long and costly. In fact, for data center operators, a 100G QSFP28 optical transceiver that is with max reach of 2km or min reach of 500m is better. Thus, MSA (Multi-Source Agreement) brings a mid-reach solution to the market. And 100G QSFP28 modules with PSM4 interface are the products in this revolution. They are much less expensive than the 10km 100GBASE-LR4 modules, and support longer distance than 100GBASE-SR4 QSFP28 optical modules.

What Are the Advantages of QSFP28 PSM4 Optical Transceiver?
In addition to the common merits of QSFP28 transceiver module, such as high bandwidth, low insertion loss, high data rate and so on, the most prominent advantage of QSFP-100G-PSM4-S is shown in its cost. It is known that CWDM4 QSFP28 optical transceiver needs an optical multiplexer/de-multiplexer, operating around 1310nm with CWDM technology. After that, the amount of the components leads to the high cost of CWDM4 modules. While 100G QSFP28 PSM4 optics, unlike 100G QSFP28 CWDM4, need these components. Thus, by comparison, CWDM4 is more expensive than PSM4. As for the other types, QSFP28 100G SR4 or QSFP28 100G LR4, both are known to be high in cost.

Factors to Be Considered for the Deployment of QSFP28 PSM4 Optical Transceiver
Compared with 100GBASE-LR4, the cost of 100GE PSM4 QSFP28 optical transceiver module is much lower. But QSFP28 PSM4 needs to connect with eight parallel single-mode optic fiber for use, while 100GBASE-LR4 optical transceiver just needs 2 single-mode optic fibers. After that, if the optical fiber link is too long, QSFP 100G PSM4 optical transceiver module will have less advantages in the deployment cost. Therefore, when deploying PSM4 QSFP28, these two aspects need to be considered: parallel single-mode optic fiber has been deployed in data center; the transmission distance of optical fiber link is within 500m.

Summary
All in all, 100GE PSM4 QSFP28 optics provides a cost-effective solution for the users who demands mid-reach transmission at low cost. Above all is about the contents Gigalight wants to share with you. If you want to know more about it, welcome to visit Gigalight official website(www.gigalight.com).

About Gigalight:
Gigalight is a design innovator in global optical interconnect field. A series of optical interconnect products include: optical transceivers, passive optical components, active optical cables, GIGAC MTP/MPO cabling, cloud programmers & checkers, etc. Three applications are mainly covered: Data Center & Cloud Computing, MAN & Broadcast Video, and Mobile Network & 5G Optical Transmission. Gigalight takes advantage of its exclusive design to provide clients with one-stop optical network devices and cost-effective products.

2018-04-24

Comparison of 3G-SDI Video Devices and 3G-SDI Video SFP Optics

With the popularization of optic fiber communication, the adoption of optic fiber for high-definition video transmission has been the reality. Furthermore, there appear various video optical termial devices in the market. The commonly-seen types include HDMI(High Definition Multimedia Interface), HD-SDI(High Definition - Serial Digital Interface), HD-CVI(High Definition Composite Video Interface), etc. Then about 3G-SDI, how much do you know about it? And what is the difference between 3G-SDI video devices and 3G-SDI video SFP optical transceiver?

What Is 3G-SDI?
3G-SDI is an upgraded version of HD-SDI with a rate of 1.485G(also regarded as 1.5G, corresponding to SMPTE-292M standard, supporting 720P) and 2.97G (also regarded as 3G, corresponding to SMPTE-424M standard, supporting full HD 1080P/60HZ). 3G-SDI supports the transmission of serial digital video signals and DVB-ASI (EN50083-9) digital video signals that are conformed to the standards of SMPTE-424M 3Gbps HD-SDI, SMPTE-292M HD-SDI or SMPTE-259M SDI. Similar to HD-SDI, 3G-SDI is also used in television studio. With the upgrading of technology, it is also widely used in global security applications such as high-end surveillance and unattended operation systems.

3G-SDI Video Devices vs. 3G-SDI Video SFP Optics: What Is the Difference?
Currently, it is full of various 3G-SDI video products in the market, including 3G-SDI optical terminal device, 3G-SDI distribution amplifier. These products can support the long-distance transmission of the irregular bit rate signal of 3G and 1.5G, and meet the various needs of the users.

However, a lot of 3G-SDI video products in the present markets have no way to pass the test of SDI pathological code. That is to say, if using these products to transmit irregular bit rate signal, the problems, such as splash screen, blank screen, blue screen and so on, will easily happen.

Actually, these 3G-SDI video products can still be used in the transmission of regular bit rate signal to some degree, but the above-mentioned problem will occur in the process of transmitting irregular bit rate signal. These problems appear with great probability under the speed rate of 3G. The reasons that bring about these problems get involved in these two aspects. One is the adopted HD-SDI optical terminal device which is not mature, or demerits in design; another is involved in cost. Most of HD-SDI optical terminal devices in the market adopt SFP optical module, which means that using 1.25G and 2.5G SFP optical module to replace video SFP optical module specially for HD-SDI optical terminal device will inevitably cause a lot of error rates when irregualr code rate is transmitted. In the application fileds of HD-SDI optical terminal device, high requirements for image quality are required. Naturally, non-smooth screen is not allowable. Therefore, the adoption of video SFP optical module specially for HD-SDI optical terminal device can ensure that these problems such as splash screen, blank screen, and blue screen, will not appear in the process of high-definition image transmission.

3G-SDI video SFP optical transceiver adopts the form factor of SFP optical transceiver module, conformed to SFP MSA and SFF-8472 protocol. Video SFP optical module can be divided into these types according to form factor , such as video SFP optical module with single transmitter/singe receiver, video SFP optical transceiver with two transmitters/two receivers, and 1.5G/3G/155M video optical module with asymmetric rate. In addition, the working wavelength and transmission distance of 3G-SDI video SFP optical module respectively are 850nm and 300m when it is matched with multimode optic fiber for application. The working wavelength and transmission distance respectively are 1310/1550 nm and 10/80 km when it is applied with single-mode optic fiber. These 3G-SDI video SFP optical module is with digital diagnostic function, avialable to monitor output optical power, bias current, supply voltage, working conditions and so on in real time.

3G-SDI video SFP optics
3G-SDI SFP optics
Similar to SFP optical module used on the exchanger, 3G-SDI SFP optical module is also used to transmit and receive optical signal. But the difference is that 3G-SDI SFP optical transceiver is used on the optical terminal device, and it plays a key role in the applications of high-definition video transmission. (If you want to know soulitions about 3G-SDI SFP, you can refer to this article: 3G-SDI SFP Solution for HD Video Transmission over Fiber)

Conclusion
Generally speaking, the biggest difference between 3G-SDI video devices and 3G-SDI video SFP optical transceiver is that 3G-SDI video SFP optical transceiver module is helpful to solve the problems, such as splash screen, blank screen, blue screen in the process of high-definition image transmission, while 3G-SDI video devices can not do it. Above all is the information about 3G-SDI video devices and 3G-SDI video SFP optical transceiver. For more information, it is at Gigalight official website(gigalight.com).

2018-04-18

Things You May Not Know about Video SFP Optics

Maybe most of people are familiar with SFP optical transceiver. However, when it comes to video SFP optical transceiver module, it may be not as familair as SFP optical transceiver to many of people. Then in this article, Gigalight (gigalight.com) will detailedly introduce the video SFP optical transceiver module.

What Is Video SFP  Optical Transceiver?
Video SFP transceiver is also regarded as digital video transceiver or Serial Digital Interface(SDI for short)video transceiver. Similar to SFP optics, video SFP optical transceiver is small, hot-pluggable one, matching with fiber optic cables for application. But what is different from SFP optics is that video SFP optics is used for video transmission. It is known that the video is transmitted in a uni-directional way, which means that the video link can be simply transmitted via a signal fiber or coax signal. The fator has been the main drive force to create different pinouts for the video SFP (as shown below). Therefore, video SFP optical transceiver can have either two optical transmitters/two optical receivers or one optical transmitter and one optical receiver.


layout of video sfp optics


With the rapid evolution of the broadcast video transmission for high-capacity HD and Ultra High-Definition (UHD) digital transmission, it is necessary to produce a kind of fiber optic transceiver that can achieve high level in video image transmission. With SDI interface, video SFP transceiver is able to support SDI video pathological signal and ensure the quality of video transmission.

Types of Video SFP Optical Transceiver
Video SFP transceiver can be divided into various types according to different factors. For example, according to operating wavelength, they can be classified into 1310nm, 1490nm, 1550nm and CWDM wavelengths video SFP transceivers; according to operating rate, they can usually be divided into 3G-SDI, 6G-SDI and 12G-SDI video SFP transceiver. The following is about the respective introduction to these three optics.

3G-SDI Video SFP optics is with a data rate up to 3Gbps, specifically designed for high performance in the presence of SDI pathological patterns for SMPTE 259M, SMPTE 344M, SMPTE 292M and SMPTE 424M serial rates. It is generally applied for television broadcasting. However, with the advancement of technology, it is also widely applied in global security applications such as high-end surveillance or unmanned systems, allowing simple designs or upgrades with full HD cameras.
http://www.gigalight.com/products_detail/productId=52.html
3G-SDI

The data rate of 6G-SDI video SFP optics is twice that of 3G-SDI transceivers, which means it is possible to deliver a payload of 6 Gbps. Therefore, they are not only designed for SDI pathological patterns for SMPTE 259M, SMPTE 344M, SMPTE 292M and SMPTE 424M serial rates but also for SMPTE 2081. 6G-SDI video SFP transceiver is often used in camera, video, security monitoring applications and 4K /HDTV/SDTV service interfaces.

12G-SDI video SFP transceiver is specifically designed for high performance in the presence of SDI pathological patterns for SMPTE 259M, SMPTE 344M, SMPTE 292M, SMPTE 424M, ST2081 and ST-2082 serial rates. They are mainly used for SMPTE ST-297-2006, ST2081 and ST-2082 compatible electrical-to-optical interfaces and UHDTV/HDTV/SDTV service interfaces.

Applications of Video SFP Optical Module
Currently, video SFP optics is mainly used in these aspects:
1. Applied in HD Camera or Monitor System
There are usually multiple HD end-devices in HD camera or monitor system. Therefore, one HD video matrix can be used as one end which provides multiple video SFP ports, and multiple HD-SDI equipments can be used as the other ends.
2. Applied for Broadcast Video Transmission
Broadcast video transmission needs high-density cabling. Thus, HD-SDI equipment with high-density video SFP ports is needed.

On account that 3G-SDI, 6G-SDI and 12G-SDI are digital baseband signals, long-distance transmission on copper cable will definitely be limited. Thus, optic fiber cables, 3G-SDI, 6G-SDI, 12G-SDI video SFP transceivers are perfect for long-distance video transmission.

Conclusion
Generally speaking, video transmission plays a key role in the daily life. To ensure the high-level video digital transmission, video SFP optical transceiver is in great favor. In addition, for the above mentioned video SFP optical transceiver module, Gigalight currently can provide or customize 3G-SDI SFP, 6G-SDI SFP+, 12G-SDI video SFP+ optical transceiver for you. More information is at Gigalight official website.

2018-04-13

What Is the Difference Between WAN and LAN?

Nowadays, LAN and WAN are widely applied in the computer networks. They exit in all places of our daily life. For example, at the back of router, there are ports noted with LAN and WAN. Although many people often use them, and they may have little knowledge of what the difference between WAN and LAN is. Then after reading this article from Gigalight, the answer will be gotten.

The Definition of LAN
LAN, the abbreviation of Local Area Network, is a type of computer network that covers a small geographic area such as home, office, a small town, any building or institute. Due to the localized nature, the data transmission rate is very high in LAN, and it can be controlled and managed by one person or small-size organization. The maintenance cost of LAN is also very low. Besides, a LAN network includes a couple of computer systems connected with each other, with one system connected to a router, modem or an outlet for internet access. The LAN network is built using inexpensive technologies  products such as Ethernet cables, network adapters and hubs. However, other wireless technologies are also available to connect the computer via a wireless access.

The Definition of WAN
WAN, the abbreviation of Wide Area Network, is a type of computer network that covers a wide geographical area and communicated area across metropolitan, countries, national boundaries, across regional and over a long distance. It use leased telecommunication lines. WAN are often used by business and government agencies to connect to achieve strong network communication among employees, clients, supplier and buyers from various parts of the world. Due to its wide coverage, LAN is hard to manage and organize. Moreover, the maintenance cost of WAN is also high compared with PANs, LANs, CANs, and MANs. In addition, WAN uses technologies such as SONET, Frame Relay, and ATM. It also allows different LANs to connect to other LANs via technology products such as routers, hubs and modems. There are four main options for connecting WANs: leased line, circuit switching, packet switching and call relay.

LAN vs. WAN: What Are the Differences?
The main difference between LAN and WAN is that LAN is a type of computer network that covers a small geographic areas, while WAN is a type of computer network that covers a broad geographical area such as metropolitan, countries, regional, etc. Except for this, they also differ from each other in these apsects:

Coverage Ranges: the coverage ranges of LAN and WAN networks are different. LAN connects computers in a small physical area, while WAN connects larger areas situated in different geographical locations.

Network Speeds: the network speeds of LAN and WAN are varied. WAN is typically slower than LAN due to the data transmission distance. The maximum speed of LAN is 1000 Mbps while WAN can only reach 150 Mbps.

Security Level: as for the security level, LAN seems to be better than WAN. Because WAN involves more people into the interconnection, there is a greater possibility of network issues.

Costs: due to the smaller network coverage, setup and maintenance costs for LAN are usually lower than that of WAN.



Note: many interconnected LANs can become the part of a larger WAN

Table about more differences of LAN and WAN:

LAN (Local Area Network)
WAN (Wide Area Network)

Application Location
a computer network covering a small geographic area, like  homes, offices, schools, or group of buildings
a computer network that covers a broad area
Speed
high speed (Up to 1000mbps)
low speed (Up to 150mbps)
Composition
using the layer 2 devices like switches, bridges and layer1 devices like hubs
using the layer 3 devices, routers and multi-layer switches
Management Mode
owned, controlled, and managed by a single person or organization; easier to maintain at relatively low costs
not owned by any organization but to exist under distributed ownership; difficult to maintain because of its wider geographical coverage and higher maintenance costs
data transmission
fewer data transmission errors
more data transmission errors


Conclusion
It is seen from the difference between LAN and WAN, both of them have their own merits and demerits. When it is hard to make a choice between them, the answer may be clear considered from the perspective of distance. Although LAN has more benefits than WAN, you still need to choose WAN when it comes to large areas networking.


About Gigalight:
Gigalight is a design innovator in global optical interconnect field. A series of optical interconnect products include: optical transceivers, passive optical components, active optical cables, GIGAC MTP/MPO cabling, cloud programmers & checkers, etc. Three applications are mainly covered: Data Center & Cloud Computing, MAN & Broadcast Video, and Mobile Network & 5G Optical Transmission. Gigalight takes advantage of its exclusive design to provide clients with one-stop optical network devices and cost-effective products.

2018-04-09

Things You Should Know about Long-Distance Optical Transceiver

With the rapid development of optical communication industry, optical modules for long reach transmission gradually satisfy the demands on the long-reach transmission of network, and are widely applied in all fields of global communication. However, which fields are they applied in? and what should be paid attention. Gigalight will have an introduction to you.

The Definition of Long-Distance Optical Transceiver
Transmission distance is regarded as one of key factor of optical module. Optical transceiver is divided into short distance optics, middle distance optics and long distance optics. The transmission distance of long-distance optical transceiver is over 30kms, but it cannot reach the maximum distance in the many situations at the process of its actual application. It is due to that the dispersion appears when optical signal transmitting in the optic fiber. To solve this problem, long-distance optical transceiver takes DFB laser only with one main wavelength as the light source. After that, the dispersion can be avoided.

Types of Long-Distance Optical Transceiver
Among these optical transceivers such as SFP optics, SFP+ optics, XFP optics, 40G QSFP+ optics and 100G QSFP28 optical transceiver, there exist some long-distance optical transceiver modules. Thereinto, long-distance SFP+ optical transceiver adopts EML laser components and optical photodetector components, which reduces the power consumption and raises the accuracy via improvements in many aspects. 40G long-distance optical module adopts driver and modulation unit in the transmitting link, the transmission distance is far more than that of existing standard 40G pluggable optical module.
  • Applications of Long-Distance Optical Transceiver
  • For the interface of switcher
  • For the interface of server
  • For the interface of network card
  • In the security monitoring filed
  • In the telecom field, including data control center and computer room, etc.
  • Ethernet, Fiber Channel(FC), Synchronous Digital Hierachy(SDH), etc.

Cautions for the Utilization of Long Distance Optics
Long-distance optical transceiver has higher requirements for the range of receiving optical power. If the optical power exceeds the range of receiving sensitivity, the failure of optical transceiver module will happen. The use tips and cautions are as follows:
  1. After the installation of long-distance optical module into the device, patch cord can not be connected at once. Using the instruction” display transceiver diagnosis interface” to read the transmitting and receiving optical power of optical transceiver module, checking whether the optical power is in the normal range.
  2. If the condition is allowable, optical power meter can be used to test the optics. After the transmitting and receiving optical power is at the normal range, the optic fiber can be connected into long distance optical transceiver.
  3. In any case, the optic fiber module can not be used to test the long-distance optical module. If it is necessary, it must be connected with the optical attenuator to make the receiving optical power within the normal receiving range.After that, the loopback test can be operated.
  4. Using the long-distance optical module, the receiving optical power must keep some margins. Besides,the actual receiving optical power is reserved at over 3dB compared with the receiving sensitivity. If it can not be achieved, the attenuator needs to be used.
  5. Long distance optical module can be used completey without attenuationin in 10km transmission application. Generally speaking, optical module over 40km will need to be added attunation. It can not be directly connected, or the ROSA is easily burnt.

Conclusion
The long-distance optical transceiver module satisfies the demand of long-distance transmission. It provides people with great convenience and is widely applied. The long-distance optical module supplied by Gigalight is rich in variety, with ultra high stability and cost effectiveness. Simultaneously, it is also highly favored by the vast number of users. In addition, Gigalight can also provide comprehensive network system solutions to help users to build a low-cost, high-performance, and manageable network system. If you are interested in it, welcome to consult.


About Gigalight:
Gigalight is a design innovator in global optical interconnect field. A series of optical interconnect products include: optical transceivers, passive optical components, active optical cables, GIGAC MTP/MPO cabling, cloud programmers & checkers, etc. Three applications are mainly covered: Data Center & Cloud Computing, MAN & Broadcast Video, and Mobile Network & 5G Optical Transmission. Gigalight takes advantage of its exclusive design to provide clients with one-stop optical network devices and cost-effective products.

2018-04-01

The Development Direction of Optical Transceiver

Optical transceiver is widely applied in the communication network. To some degree, users’ more demands on optical communication network promotes the development of optical transceiver module. Nowadays' communication network is developed toward higher information transmission rate, smaller in volume of communication devices. Then how about the development direction of optical transceiver? In this article, Gigalight will have an introduction to it.

The Development Direction of Optical Transceiver
  1. Faster-Higher Transmission Rate
People demand more for the amount of information transmission, and require higher rate of information transmission. The rate of optical module is developd from the Mbit, Gigabit to 40G, 100G and even more.


  1. Smaller-Miniacturization
In the gradually-rapid competition of optical communication market, the volume of communication device is also smaller. To meet the requirements of optical communication device, optical transceiver is gradually developed into the highly-intergrated package. The volume of optical module is decreased with the change of optical interface and connection form. In addition, the package of optical module is also developed from the metal package to the plastic package correspondingly.
  1. Lower- Low Power Dissipation
In order to adapt to smaller and smaller volume of communication devices, interface density and interface boards, optical modules need to reduce power consumption. Using gallium arsenide technology, development technology, preamplifier can make chip product with silicon germanium reduce power consumption. In addition, the non-cooling laser can further reduce the power consumption of the optical module.
  1. Farther - Longer Transmission Reach
On account that the laying distance of optical network is longer, the transmission distance is also required longer. The typical remote optical module without the condition of amplification can transmit 100km. But due to that there exists some certain loss and dispersion in the transmission process of optical signal on the fiber, the transmission distance of optical transceiver will be limited. After that, many remote optical transceiver module will choose to the working frequency band of 1550nm to make the transmission distance longer.
  1. Simplified Management- Hot Plugging
Hot plugging means that the optical module can connect or disconnect with a device without cutting off the power supply. The network manager can upgrade and expand the system without closing the network, and it does not affect the online user. Hot plugging also simplifies the maintenance work and enables the end-users to manage their optical modules well. At the same time, because of the heat transfer performance, optical module allows network managers to formulate the link distance, transmission costs and all network topology according to the network upgrade requirements, without changing all system boards.

In order to meet the needs of people, optical module is developed towards the direction of "faster, smaller, lower and farther". As the main series of optical transceiver, SFP, SFP+, XFP, QSFP+, CFP/CFP2/CFP4, QSFP28 and other optical modules produced by Gigalight, are also constantly innovated under the guide of the development trend,in the great favor of the vast number of users.

2018-03-02

The Latest QSFP28 Optical Transceivers: QSFP28 4WDM and QSFP28 ER4 Lite


The 100G optical module is with a variety of packaging forms, mainly including the early CFP/CFP2/CFP4 and the new-generation QSFP28. As a hot solution of 100G network, CFP series and QSFP28 optical transceiver have their own advantages. They all play a role in the specific application of 100G network. Currently, it seems that QSFP28 series optical transceiver is in greater favor than CFP series opticcal module transceiver. With respect to QSFP28 series optical module, there are two new types: 100G QSFP28 ER4 Lite optical transceiver module and 100G QSFP28 4WDM optical transceiver module. Then Gigalight will have an introduction to them in this article.
An Introduction to QSFP28 4WDM Optical Transceiver
4WDM(4-Wavelength Wavelength Division Multiplexing) optical module is defined by 4WDM MSA, targeted for longer reaches, lower costs, and lower power consumption, smaller form factor(QSFP28 form factor is usually preferred). 100G QSFP28 4WDM optics have three specifications including 4WDM-10, 4WDM-20, 4WDM-40. 4WDM-10 is one type of 100G (4x25G) optical transceivers for the 10 km based on the CWDM4 wavelength grid; 4WDM-20 and 4WDM-40 are types of 100G (4x25G) optical transceivers respectively for 20kms and 40kms based on the LAN-WDM wavelength grid over duplex single-mode fiber (SMF). With respect to the benefits of 4WDM, its main advantages are lower in cost and power dissipation, and longer in transmission distance.
An Introduction to QSFP28 ER4 Lite Optical Transceiver
IEEE 802.3ba defines that the 100GBASE-LR4 / 100GBASE-ER4 series has a BER requirement of better than 1E-12 w / o FEC for optical modules. Since the receiving sensitivity of 100GBASE-ER4 is not satisfied with the existing APD technology, the SOA size is too large for the QSFP28 series; many optical module companies in the industry defined a non-standard 100GBASE-ER4 Lite with QSFP28 package that the largest transmission distance is up to 30km without FEC.
The receiving sensitivity of 100GBASE-ER4 Lite 30km has no clear definition in IEEE802.3ba. At the current level of 100G APD ROSA, the average of OMA Sensitivity is around -17dbm (BER 1E-12@25.78125Gbps). The description of the100GBASE-ER4 Lite products in the industry is defined as 30km w/o FEC, 40km with FEC.
100G QSFP28 ER4 Lite vs. 100G QSFP28 4WDM: What Are the Difference?
The differences between QSFP28 ER4 Lite and QSFP28 4WDM are shown as the table:

QSFP28 4WDM vs. QSFP28 ER4 Lite

In addition, in the aspect of application, 100G QSFP28 ER4 Lite is available for both 100GE and OTU4 application, while 100G QSFP28 4WDM 40km is only available for 100GE application.
Summary
The migration of current network infrastructure to 100G systems is inevitable, and a growing number of enterprises require 100G client port to extend up to 40km without the use of expensive optical amplifiers. Thefore, the new ER4 Lite and 4WDM optical transceiver enable cost-effective 100G 40km pluggable solutions in compact QSFP28 transceivers that use Forward Error Correction (FEC) and APD-based receivers. Such evolution is very exciting for not only everyone involved in its development and construction, but also for all those who seek a simple, reliable and cost-effective solution to extend the reach of their networks, without expensive network upgrades. Gigalight, as the design innovator in global optical interconnect field, has pushed out the latest 100G QSFP28 4WDM 40KM optical transceiver and 100G QSFP28 ER4 Lite 40KM optical transceiver. More details are at Gigalight(gigalight.com)

2018-02-27

200G&400G: Which One Will Be the Rising Star after 100G Optics in the Market ?

With the rapid development of optical communication and Internet in recent years, users' demand for the network has also surged, which leads to the rapid growth of Telecom backbone traffic at a speed of 50% to 80% per year. In order to follow the development trend of 10G-40G-100G/10G-25G-100G in the optical communication market, 100G optical module arises with the trend and rises rapidly in the market. It plays a very important role in building 100G network system.
Since the advent of 100G network, the industry alliance institutions such as the IEEE, Multi Source Agreement(MSA) have formulated multiple standards for the 100G optical transceiver.
According to the differences of form factor, 100G optical transceivers can be divided into CFP/CFP2/CFP4, CXP and QSFP28 optics. The detailed parameters are shown as below:
Standard
Connector &Fiber Type
Transmission Distance
24 fiber MPO, parallel multimode fiber, with 10 transmitting ports and 10 receiving ports,850mn
OM3,100m OM4,150m
12 fiber MPO, parallel multimode fiber, with 4 transmitting ports and 4 receiving ports,850mn
OM4 100m
duplex LC, single mode fiber,1310mn,4x25G WDM
10km
100GBASE-ER4
12 fiber MPO, parallel multimode fiber, with 4 transmitting ports and 4 receiving ports,850mn
40km
12 fiber MPO, parallel single mode fiber, with 4 transmitting ports and 4 receiving ports,1310mn
500m
duplex LC, single mode fiber,1271-1331mn,4x25GCWDM
2km
100G SWDM4
Duplex LC, multimode fiber,850-950mn,4x25G SWDM,
OM3,TBO WBMMF,4TBD
100G CLR4
duplex LC, single mode fiber,1271-1331mn,4x25G CWDM
2km

Thereinto, the QSFP28 optical module has the same design concept as the QSFP optical module. It is with four transmitting and receiving ports; the transmission rate of each channel reach up to 28Gbps. In addition, QSFP28 optic fiber transceiver is with these advantages such as small size, power consumption(no more than 3.5W). Currently, mainstream packaging of 100G optical module is paid more attention such as 100G QSFP28 optical module.
At the same time that 100G optical transceivers achieve 100G optical transmission, a series of major technological changes happen, including polarization multiplexing phase modulation technology, the third generation super-strong error correction coding technology of digital coherent receiving technology, etc. On account that these techs adapt to the changes of market trends, they become the mainstream of market.
Meanwhile, the new applications, such as high-definition video 4K, live broadcast, VR etc, promote the fast growth of network traffic. Simultaneously, these emerging applications such as cloud computing, IaaS services, big data, etc, also raise higher requirements for data transmission in the interior of data center. These  promote the continuous development of 100G optical module market.
Although 100G optical module has become the market mainstream, and the requirements for bandwidth, port density, power   consumption of system are continuously improved, which further pushes the development of technology toward the system of 200G/400G/higher rate.
With the continuous revision of 200G/400G standard, the standard of 200G/400G optical module has always been synchronized. At present, there have been manufacturers pushed out module samples for advertisement. In fact, for the next-stage development, the adoption of 200G or 400G has always been the controversial object in the industry. It is believed that the competition among optical transceivers will be more  intense when it is in the commercial phase.
The main type of 400G optical module includes CDFP, CFP8, QSFP-DD and OSFP. CDFP is the earliest type of 400G optical module, which has already been in version 3.0 from 2014 to now. CFP8 is a new member of the CFP family after CFP4, which is with larger size. QSFP-DD is a popular type at present; in addition that its length is slightly longer, it is basically same as QSFP28.
OSFP is a new type of 400G optical module. It is with eight high-speed electrical channels; it still supports 32 OSFP ports in the front panel per 1U, and 12.8Tbps can be available per 1U. With the integrated radiator, the heat dissipation performance can be greatly improved, and the module with 15W power can be realized in the switch chassis with the traditional air flow.
Compared with 100G, the 400G system can further enhance the network capacity on the basis of 100G and reduce the transmission cost per bit. Because in the aspects of 40G/100G products, the four channel parallel architecture are taken as the most cost-effective high bandwidth optical packaging platform. It has been proven that whether 4x50Gx2 architecture or 4X100G architecture will also be most cost-effective in future.
Although the 400G module also supports the application of 200G, and the module type for the 200G application is MicroQSFP.
MicroQSFP is with 4 differential pairs in total; it can support the current 100G application. Compared with 100G QSFP28 optical transceiver, it is smaller in size but its panel density has increased by 33%. Thus, it will dominate in volume and panel density. In addition, it will achieve better cooling effect due to that it is with radiator.
With the rapid development of mobile Internet, cloud computing, big data and other technologies, the whole communication industry needs to upgrade the network to a higher level after 10G-40G-100G or 10G-25G-100G. For 200G/400G, which one will be the rising star after 100G? It is still hard to draw the conclusion. However, in terms of the current market situation and technological development, the 400G optical module is with more advantages.
Note: More article resources are at gigalight.com.