#QSFP-4X10G-LR-S

[cloriscai-blog1]

Three Types of 40G QSFP+ Transceivers for Long Distance Transmission

Nowadays, people have access to data at all times and at everywhere, which gives rise to the rapid development of big data technology. During the application of big data technology, transceiver has become an indispensable component, which can help executives to get their data in real-time. Recently, 40GbE network has replaced 10G Ethernet network and has been used worldwide. For 40GbE network deployment, high-density cabling is the basic requirement. Also, optical components for high-speed data transmission are necessary. This article aims to introduce three types of 40G QSFP+ transceivers for long distance transmission—QSFP-4X10GE-IR, QSFP-40G-PLRL4 and QSFP-4X10G-LR-S.

QSFP-4X10GE-IR Transceiver

Designed with MTP interface, the parallel QSFP-4X10GE-IR transceiver offers 4 independent transmit and receive channels, each capable of 10Gbps operation. It utilizes 12-ribbon single-mode fiber cable with female MTP/MPO connector to realize 40Gbps data link with transmission distances up to 1 km.

QSFP-40G-PLRL4 Transceiver

The QSFP-40G-PLRL4 transceiver uses 12-fiber MTP interface to achieve 40Gbps parallel transmission, supporting maximum data link lengths up to 1.4 km. The cable type required for QSFP-40G-PLRL4 transceiver is an APC (angle polished connector) single-mode 12-fiber MTP cable. APC is the only available type for single-mode MTP-12 fiber.

QSFP-4X10G-LR-S Transceiver

The QSFP-4X10G-LR-S transceiver is a parallel 40Gbps QSFP+ optical module. It supports link lengths of up to 10 km on G.652 single-mode fiber. It enables high-bandwidth 40G optical links over 12-fiber parallel fiber terminated with MPO/MTP female connector. It can also be used in a 4x10G mode for interoperability with 10GBASE-LR interfaces up to 10 km.

When reading this, you may find that all these three types of 40G transceivers are designed with MTP interface and use parallel transmission. In parallel transmission, data signals are sent sequentially on the same channel. In addition, they all use 1310nm wavelength and can transfer data signals up to at least 1 km. What’s more, they are compatible with the Small Form Factor Pluggable Multi-Sourcing Agreement (MSA) and they support Digital optical monitoring (DOM).

Working Principle

Because the structures of these three types of 40G transceivers are similar, their working principles are similar, too. The single-mode cable terminated with 12-fiber MTP connector plugged into the 40G transceiver carries the 40G signal over only 8 of the 12 fibers, remaining 4 fibers unused. The 8 used fibers are mapped as 4x10G Tx and Rx pairs. We can easily understand the working principle of these three types of 40G QSFP+ transceivers from the figure below. In the transmit side, the transmitter converts parallel electrical input signals into parallel optical signals through the use of a laser array. Then the parallel optical signals are transmitted parallelly through the single-mode fiber ribbon terminated with MTP/MPO connector. While in the receive side, the receiver converts parallel optical input signals via a photo detector array into parallel electrical output signals.

Application

Many data centers are in the process of 10G to 40G migration. To make migration path smooth, we can use 40G transceivers together with MTP cable. Take QSFP-40G-PLRL4 transceiver for example, we can simply use MTP-LC harness cable to connect one QSFP-40G-PLRL4 transceiver and four 10GBASE-LR SFP+ transceivers. Here is a figure for you to have a better understanding of the connectivity. In addition, for 40 connectivity, we can use MTP trunk cable to connect two QSFP-40G-PLRL4 transceivers to make the optical links. Using 40G QSFP+ transceiver for high-speed long distance transmission over single-mode fiber is a cost-effective solution.

Conclusion

With special structures, MTP components are popular with data center managers for fast installation, high density and high performance cabling. QSFP-4X10GE-IR, QSFP-40G-PLRL4 and QSFP-4X10G-LR-S these three 40G QSFP+ transceivers have special interface designs which can be compatible with single-mode MTP connector and support long distance transmission. During the deployment of 40G QSFP+ module, selecting proper MTP assemblies are also essential to successfully accomplish the link.

Originally published at http://www.fiber-optic-cable-sale.com/some-thoughts-required-before-mtp-cabling.html

[thoughtfulsaladgarden]

Answers to frequently asked questions about optical modules

Optical module is an optoelectronic device for photoelectric and electro-optical conversion. The transmitting end of the optical module converts the electrical signal into an optical signal, and the receiving end converts the optical signal into an electrical signal. This article will answer the common questions about optical modules in optical communication.

 1. What does passive and active module mean?

 The passive and active modules are for AOC high-speed cable and DAC copper cable. The AOC module is equipped with laser, detector, MCU, driver chip, transimpedance amplifier and limiting amplifier, so it is an active cable; Similarly, ACC copper cable module is also an active cable with signal equalization and amplification chip, EEPROM, resistance, capacitance, inductance and copper wire. The DAC copper cable has no signal equalization and amplification chip, only EEPROM, resistance, capacitance, inductance and copper wire, so it is a passive cable.

 From the perspective of circuit properties, passive devices have three basic characteristics: 1)They either consume electric energy or convert electric energy into different forms of other energy. 2)Just input the signal and can work normally without external power supply. 3)Common passive electronic devices passive devices in electronic systems can be divided into circuit devices and connection devices according to their circuit functions.

 2. Issues related to FEC function of 25G/40G/100G optical module

 FEC is an error correction technique that solves the problem in optical signal transmission when part of the optical signal at the transmitting end is scrambled during transmission, resulting in a misjudgment at the receiving end. Forward Error Correction (FEC) is used in 100G and other high-speed optical modules. Generally speaking, when this function is turned on, the transmission distance of the high-speed optical module will be longer. 10G and below 10G optical modules, 40G optical modules, 100G LR4 optical modules do not need to open FEC; 25G SR, 25G LR, 25G AOC, 25G copper, 100G SR4, 100G PSM4, 100G AOC, 100G CWDM4, 100G QSFP28 ER4, 100G 4WDM-40, 100G copper cable need to open FEC.

3. Why some optical modules can be divided into four channels and some can't?

MPO interface optical modules all can be divided into four channels, such as: 40G-QSFP-SR-MM850, 40G-QSFP-LSR-MM850, QSFP28 SR 100G MM850 multimode optical module, 40G-QSFP-LR4-PSM-SM1310, 100G-QSFP-iLR4-PSM-SM1310 single-mode Optical modules; the above 40G/100G optical modules work the same, are 4x10G, 4x25G design scheme, using a point four fiber patch cable, one end of the MPO 12 interface is 8 cores (4-way transmit, 4-way receive, the middle 4 idle), the other end of 8 LC connectors.

4. What are the parameters of the optical module? What do they mean?

The main parameters of optical module include rate(bandwidth), transmission distance, central wavelength and interface type.

 The DDM monitoring parameters of optical module digital diagnosis include working voltage, shell temperature, bias current, TX power and Rx power; The signal quality parameters of optical module include transmitted optical power, extinction ratio, transmitted optical eye diagram, jitter, margin, received optical power, received sensitivity, output electric eye diagram and bit error rate.

The manufacturer burns the identification code in the optical module register according to the protocol. The switch software accesses the optical module register according to the protocol rules, then identifies the optical module and issues the configuration.

 5. What’s the difference of 40G and 100G optical module?

 The interface type of 40G/100G optical module is the same as the communication principle, and the single-mode optical fiber used is the same. The multi-mode optical fiber grade OM2 and above is required for 40G multi-mode optical module, while the multi-mode optical fiber grade OM3 and above is required for 100G multi-mode optical module; For 40G-QSFP-SR-mm850, 40G-QSFP-LR-mm850 and 100G-QSFP-SR-mm850 optical modules, it is required to use "MPO/MTP-PC-Female - MPO/MTP-PC-Female, multi-mode, OM3-300, 12 core, Φ 3.0mm, LSZH, water blue, B-type" optical fiber jumper.

 Fiber Mall 100G QSFP28 SR optical transceiver

  6. How does BIDI type module achieve using only one fiber?

 Usually, optical modules have two different fibers for transmitting and receiving.

Bidi (BI direction): in the same optical fiber, two optical signals with different wavelengths are used to transmit and receive optical signals in two directions respectively, and a prism is used inside the module to distinguish the optical signals in two directions. For example, like QSFP28 100G SRBD, since the laser wavelengths sent by the modules at both ends are inconsistent, pay attention to pairing when using Bidi modules.

 7. What are the types and construction principles of optical fibers?

 The optical fiber is a very fine white glass core, which must be covered by several layers of protective structures before use. The coated cable is an optical cable. Fiber types are divided into single-mode fiber and multimode fiber.

 Differences between single-mode and multimode fibers:

1) Single mode fiber uses solid-state laser as light source, and multi-mode fiber uses light-emitting diode as light source;

2) Single mode fiber has long transmission frequency bandwidth and transmission distance, but needs laser source, which has high cost, low transmission speed, short distance and low cost of multi-mode fiber;

3) The core diameter and dispersion of single-mode fiber are small, and only one mode transmission is allowed;

4) Multimode fiber has large core diameter and dispersion, allowing hundreds of modes of transmission;

5) Multimode optical cable has a thick core and the price will be relatively expensive.

[lisamelendezblog]

25G Transceiver FAQ

Written by Craig Pasek, Product Manager, Transceiver Modules Group

I’ve posted a few blogs about 25G transceivers (here, here, and here). Here’s an FAQ to address questions that have arisen from the significant uptick in the use of 25G transceivers, which is driven by high bandwidth demands in enterprise, data center and service provider applications.

Q: Why is the use of 25G increasing?

Many network operators have chosen 25G instead of multiple 10G’s, because 25G provides 2.5x bandwidth of the 10G in the same familiar SFP form factor at approximately the same power. This has enabled network equipment manufacturers to provide higher bandwidth connectivity. Rack mountable switches and routers populated with 12 ports, 24 ports, and 48 ports on a single 1 RU faceplate are common for SFP.

Q: What is the cost per bit of 25G?

25G provides 2.5x the bandwidth of 10G at a slight increase in cost. The result is nearly a 50% reduction in the cost per bit.

Q: Is 25G standardized?

The IEEE (Institute of Electrical and Electronic Engineers) has standardized 25G. See IEEE802.3by and IEEE802.3cc for the details.

Q: Which popular 25G transceivers are available today ?

MMF (Multi Mode Fiber): SFP-10/25G-CSR-S (up to 400m on OM4) SFP-25G-SR-S (up to 100m on OM4)

SMF (Single Mode Fiber): SFP-10/25G-LR (up to 10km)

Cables: SFP-25G-AOCxxM (up to 10m) SFP-H25G-CUxM (up to 5m)

Q: What is SFP28?

SFP28 is the standardized pluggable form factor for 25G transceivers. It has the same mechanical dimensions as 10G SFP+ and 1G SFP. The electrical interface of 25G was envisioned to operate up to 28Gbps to accommodate overhead for a 25Gbps signal.  Today most 25G transceivers operate at a 25.78125Gbps nominal data rate. The standards body that defines SFP28 is SFF (Small Form Factor Committee).

Q: What is SR?

SR is Short Reach, and generally refers to transceivers that operate over MMF up to a few 100 meters.

Q: What is LR?

LR is Long Reach, and generally refers to transceivers that operate over SMF at up to 10km.

Q: What does “AOC” mean?

AOC is Active Optical Cable.  These cables are generally 1 to 10 meters in length and have active components that connect SFP28 hosts at 25G.

Q: What does “DAC” mean?

DAC is Direct Attached Cable. These cables are generally 1 to 5 meters in length and are passive.

Q: What does “10/25G” mean?

These are dual-rate transceivers that support both 10G and 25G rates.

Q: Explain “CSR”

“Cisco Short Reach” is Cisco technology that enables reach of 300/400m over OM3/4 MMF.

Note: The IEEE standard 25G SR’s reach is only up to 70/100m over OM3/4 MMF.

Q: What does “breakout” mode mean?

Breakout enables multilane QSFP transceivers to interoperate with single lane SFP transceivers.

For example, up to 4x SFP-25G-SR-S can interoperate with a QSFP-100G-SR4-S using a MMF breakout cable; 4x SFP-10/25G-LR-S interoperates with a QSFP-4X10G-LR-S (at 10G) and a QSFP-100G-PSM4-S (at 25G) using SMF breakout cable; and 4x SFP-10/25G-CSR-S interoperates with a QSFP-40G-SR4-S (at 10G) or a QSFP-100G-SR4-S (at 25G) using a MMF breakout cable.

Q: What new technology is in 25G transceivers?

25G transceivers have CDR (Clock Data Recovery) circuits and generally require FEC (Forward Error Correction).

Q: When is FEC needed?

FEC decreases the BER to 10-12. For 25G, RS-FEC is used when the pre-FEC BER is above 5×10-5 and FC-FEC is used when the pre-FEC BER is above 10-8.  Additional details can be found in IEEE802.3 Clause 74 for FC-FEC and Clause 91 for RS-FEC.

Q: What is BER?

BER refers to Bit Error Rate.

Q: What Cisco host platforms support 25G transceivers ?

See the Cisco transceiver Compatibility Matrix: https://tmgmatrix.cisco.com/home

Q: Where can additional information about Cisco 25G transceivers be found ?

See the Cisco 25G datasheet: https://www.cisco.com/c/en/us/products/collateral/interfaces-modules/transceiver-modules/datasheet-c78-736950.html

25G Transceiver FAQ published first on https://brightendentalhouston.tumblr.com/

[keygenix]

25G Transceiver FAQ

Written by Craig Pasek, Product Manager, Transceiver Modules Group

I’ve posted a few blogs about 25G transceivers (here, here, and here). Here’s an FAQ to address questions that have arisen from the significant uptick in the use of 25G transceivers, which is driven by high bandwidth demands in enterprise, data center and service provider applications.

Q: Why is the use of 25G increasing?

Many network operators have chosen 25G instead of multiple 10G’s, because 25G provides 2.5x bandwidth of the 10G in the same familiar SFP form factor at approximately the same power. This has enabled network equipment manufacturers to provide higher bandwidth connectivity. Rack mountable switches and routers populated with 12 ports, 24 ports, and 48 ports on a single 1 RU faceplate are common for SFP.

Q: What is the cost per bit of 25G?

25G provides 2.5x the bandwidth of 10G at a slight increase in cost. The result is nearly a 50% reduction in the cost per bit.

Q: Is 25G standardized?

The IEEE (Institute of Electrical and Electronic Engineers) has standardized 25G. See IEEE802.3by and IEEE802.3cc for the details.

Q: Which popular 25G transceivers are available today ?

MMF (Multi Mode Fiber): SFP-10/25G-CSR-S (up to 400m on OM4) SFP-25G-SR-S (up to 100m on OM4)

SMF (Single Mode Fiber): SFP-10/25G-LR (up to 10km)

Cables: SFP-25G-AOCxxM (up to 10m) SFP-H25G-CUxM (up to 5m)

Q: What is SFP28?

SFP28 is the standardized pluggable form factor for 25G transceivers. It has the same mechanical dimensions as 10G SFP+ and 1G SFP. The electrical interface of 25G was envisioned to operate up to 28Gbps to accommodate overhead for a 25Gbps signal.  Today most 25G transceivers operate at a 25.78125Gbps nominal data rate. The standards body that defines SFP28 is SFF (Small Form Factor Committee).

Q: What is SR?

SR is Short Reach, and generally refers to transceivers that operate over MMF up to a few 100 meters.

Q: What is LR?

LR is Long Reach, and generally refers to transceivers that operate over SMF at up to 10km.

Q: What does “AOC” mean?

AOC is Active Optical Cable.  These cables are generally 1 to 10 meters in length and have active components that connect SFP28 hosts at 25G.

Q: What does “DAC” mean?

DAC is Direct Attached Cable. These cables are generally 1 to 5 meters in length and are passive.

Q: What does “10/25G” mean?

These are dual-rate transceivers that support both 10G and 25G rates.

Q: Explain “CSR”

“Cisco Short Reach” is Cisco technology that enables reach of 300/400m over OM3/4 MMF.

Note: The IEEE standard 25G SR’s reach is only up to 70/100m over OM3/4 MMF.

Q: What does “breakout” mode mean?

Breakout enables multilane QSFP transceivers to interoperate with single lane SFP transceivers.

For example, up to 4x SFP-25G-SR-S can interoperate with a QSFP-100G-SR4-S using a MMF breakout cable; 4x SFP-10/25G-LR-S interoperates with a QSFP-4X10G-LR-S (at 10G) and a QSFP-100G-PSM4-S (at 25G) using SMF breakout cable; and 4x SFP-10/25G-CSR-S interoperates with a QSFP-40G-SR4-S (at 10G) or a QSFP-100G-SR4-S (at 25G) using a MMF breakout cable.

Q: What new technology is in 25G transceivers?

25G transceivers have CDR (Clock Data Recovery) circuits and generally require FEC (Forward Error Correction).

Q: When is FEC needed?

FEC decreases the BER to 10-12. For 25G, RS-FEC is used when the pre-FEC BER is above 5×10-5 and FC-FEC is used when the pre-FEC BER is above 10-8.  Additional details can be found in IEEE802.3 Clause 74 for FC-FEC and Clause 91 for RS-FEC.

Q: What is BER?

BER refers to Bit Error Rate.

Q: What Cisco host platforms support 25G transceivers ?

See the Cisco transceiver Compatibility Matrix: https://tmgmatrix.cisco.com/home

Q: Where can additional information about Cisco 25G transceivers be found ?

See the Cisco 25G datasheet: https://www.cisco.com/c/en/us/products/collateral/interfaces-modules/transceiver-modules/datasheet-c78-736950.html

25G Transceiver FAQ published first on https://medium.com/@JioHowpage

[sandyzhou08]

Cisco QSFP-4X10G-LR-S Compatible 4x10GBASE-LR QSFP+ 1310nm 10km MTP/MPO DOM Transceiver Module

[katherinewangfs-blog]

Datasheet of 40G QSFP Module

When it comes to selecting 40G QSFP modules, customers may be dazzled by the various products provided by various suppliers. Some of them may directly purchase from big brands like Cisco. Actually, except for those well known brands, many other rising companies like FS also provide 40G QSFP transceivers, which usually come at a much lower price with with a high quality. This post will demonstrate the 40G QSFP Datasheet provided by FS.

40G QSFP Datasheet: QSFP 40G SR4 Datasheet

The S-Class FS 40GBASE-SR4 QSFP module supports link lengths of 100 and 150 meters, respectively, on laser-optimized OM3 and OM4 multimode fibers. QSFP 40G SR4 transceiver is aligned to IEEE 40GBASE-SR4 optical specifications which support high-bandwidth 40G optical links over 12-fiber parallel fiber terminated with MPO/MTP multifiber female connectors. Because IEEE 40GBASE-SR4 does not support 4x10G breakout connectivity to 10GBASE-SR, see QSFP-40G-SR4 or QSFP-40G-CSR4 for such applications. QSFP 40G SR4 does not support FCoE. More specific details of FS QSFP 40G SR4 Datasheet can be obtained in the table below.

40G QSFP Datasheet: QSFP 40G LR4 S Datasheet

The FS 40GBASE-LR4 QSFP module supports link lengths of up to 10 kilometer over a standard pair of G.652 SMF (single-mode fiber) with duplex LC connectors. The QSFP-40G-LR4-S module supports 40GBASE Ethernet rate only. The 40 Gigabit Ethernet signal is carried over four wavelengths. Multiplexing and demultiplexing of the four wavelengths are managed in the device. QSFP-40G-LR4-S does not support FCoE. More information have been shown in the following QSFP 40g LR4 S Datasheet.

QSFP+ SR4 vs QSFP+ LR4: Which One to Choose?

After going through QSFP 40G SR4 Datasheet and QSFP 40g LR4 S Datasheet, you may have had a basic understanding of QSFP 40G SR4 and QSFP 40g LR4. SR is short for short reach and LR represents Long Reach. The most obvious difference is that 40GBASE-SR4 is with MPO/MTP port while the 40GBASE-LR4 is with the Duplex LC port. The cost of 40GBASE-SR4 QSFP+ is more cheaper than the 40GBASE-LR4 QSFP+. Additionally, the fiber cost of the cabling with them also have a big difference. Because SMF cabling is more expensive than the MMF cabling.

Summary

As speeds have increased to 40G, the quad small form-factor pluggable (QSFP) has become the high-density transceiver of choice. Hoping this post on FS 40G QSFP Datasheet may help you when selecting 40G optical transceivers.

[penguincom-blog]

Cisco 4x10GBASE-LR QSFP Modules for SMF - For Optical Network, Data Networking - 882658849978