What Is SFP?
SFP, short for small form-factor pluggable is a compact, hot-pluggable transceiver used for both telecommunication and data communications applications. SFP transceiver can be regarded as the upgrade version of GBIC module. Unlike GBIC with SC fiber optic interface, SFP is with LC interface and the main body size of SFP is only about half of GBIC so that it can save more space. SFP interfaces a network device mother board (for a router, switch, media converter or similar devices) to a fiber optic or copper networking cable. Meanwhile, SFP is a popular industry format supported by many network component vendors. It is designed to support SONET, Gigabit Ethernet, Fibre Channel, and other communications standards.

Standardization
The SFP transceiver is not standardized by any official standards body, but rather is specified by a Multi-source Agreement (MSA) among competing manufacturers. The SFP was designed after the GBIC interface, and allows greater port density (number of transceivers per cm along the edge of a mother board) than the GBIC, which is why SFP is also known as mini-GBIC. The related Small Form Factor transceiver is similar in size to the SFP, but is soldered to the host board as a through-hole device, rather than plugged into an edge-card socket.

However, as a practical matter, some networking equipment manufacturers engage in vendor lock-in practices whereby they deliberately break compatibility with "generic" SFPs by adding a check in the device's firmware that will enable only the vendor's own modules. For example, in 2003 during a routine Internet Operating System (IOS) update on their Catalyst line of switches, Cisco added a feature that would cause the switch to reject optical modules that were not deemed "Cisco brand".

Types of SFP Transceiver Modules
SFP Transceivers are available with a variety of transmitter and receiver types, allowing users to select the appropriate transceiver for each link to provide the required optical reach over the available optical fiber type (e.g. multi-mode fiber or single-mode fiber).

In the market, SFP transceiver modules are commonly available in several different categories:

For multi-mode fiber, with black or beige extraction lever
SX - 850 nm, for a maximum of 550 m at 1.25 Gbit/s (Gigabit Ethernet) or 150m at 4.25 Gbit/s (Fibre Channel)

For single-mode fiber, with blue extraction lever
LX - 1310 nm, for distances up to 10 km
EX - 1310 nm,for distances up to 40 km
ZX - 1550 nm, for distances up to 80 km
BX - 1490 nm 1310nm, for distances up to 10 km
1550 nm 40 km (XD), 80 km (ZX), 120 km (EX or EZX)

For copper twisted pair cabling
1000BASE-T - these modules incorporate significant interface circuitry and can only be used for Gigabit Ethernet, as that is the interface they implement. They are not compatible with (or rather: do not have equivalents for) Fibre channel or SONET.

For WDM (Wavelength Division Multiplex) system
BiDi SFP (Bidirectional SFP) for bi-directional traffic on a single fiber. Coupled with CWDM (Coarse Wavelength Division Multiplexing), these double the traffic density of fiber links
CWDM and DWDM (Dense Wavelength Division Multiplexing) transceivers at various wavelengths achieving various maximum distances

 Applications of SFP Transceiver Module
SFP is expected to perform at data speed of up to five gigabits per second (5Gbps), and possibly higher. Because SFP module can be easily interchanged, so electro-optical or fiber optic networks can be upgraded and maintained more conveniently than that with traditional soldered-in modules. Owing to its low cost, low profile and the ability to provide a connection to different types of optical fibers, SFP transceiver can result in a substantial cost savings, both in maintenance and in upgrading efforts. SFP transceiver is available with multi-mode single-mode fiber optics, allowing users to select the appropriate transceiver for each link in order to provide the required optical reach over the available optical fiber type. It is also available with copper cable interfaces, which allows a host device designed primarily for optical fiber communications to communicate over unshielded twisted pair networking cables. Modern optical SFP transceiver supports DDM (Digital Diagnostics Monitoring) functions, also known as DOM (Digital Optical Monitoring). This feature gives users the ability to monitor the real-time parameters of SFP transceiver, such as optical output power, optical input power, temperature, laser-bias current and transceiver supply voltage.

Click on Link to buy Compufox SFP Transceivers

This document describes how the Cisco^® 40-Gbps QSFP BiDi transceiver reduces overall costs and installation time for customers migrating data center aggregation links to 40-Gbps connections.

As a result of data center consolidation, server virtualization, and new applications that require higher data transport rates, the data center network is shifting to 10 Gbps at the access layer and 40 Gbps at the aggregation layer. A broad portfolio of high-performance and high-density 10- and 40-Gbps Cisco Nexus^® Family switches is available at attractive prices for this transition. However, to support 40-Gbps connectivity, data center architects are challenged by the need for a major upgrade of the cabling infrastructure, which can be too expensive or disruptive to allow data centers to quickly adopt and migrate to the 40-Gbps technology.

Cisco solves this problem with innovative 40-Gbps Quad Small Form-Factor Pluggable (QSFP) bidirectional (BiDi) technology that allows reuse of existing 10-Gbps fiber infrastructure for 40-Gbps connections.

Challenges with Existing 40-Gbps Transceivers

Standard short-reach (SR) 10- and 40-Gbps transceivers use fundamentally different connectivity formats, requiring fiber cabling infrastructure to be redesigned and replaced. 10-Gbps SR transceivers operate over dual-fiber multimode fiber (MMF) with LC connectors, and 40-Gbps SR protocols, such as SR4 and CSR4, operate over MMF ribbon with MPO connectors. As a result, 40-Gbps MPO-based SR4 transceivers cannot reuse aggregation fiber infrastructure built for 10-Gbps connectivity.

Connector type is not the only concern. Whereas 10-Gbps SR transceivers require 2 fiber strands per 10-Gbps link, 40-Gbps SR4 and CSR4 transceivers require a theoretical minimum of 8 fiber strands, and often 12 fiber strands in practice. The reason for this requirement is that 40-Gbps SR4 and CSR4 use 4 parallel fiber pairs (8 fiber strands) at 10-Gbps each for a total of 40-Gbps full duplex, as shown in Figure 1. However, both use MPO-12 connectors, which terminate 12-fiber ribbons. As a result, 4 fiber strands in each connection are unused and wasted.

To economize trunk fiber in a structured cabling environment, a 2 x 3 MPO fiber conversion module could combine three SR4 links onto two 12-fiber ribbon cables. But even then the 40-Gbps SR4 trunk still uses 8 fiber strands per link compared to 2 fiber strands in the case of 10-Gbps SR.

At best, the connector change and increased fiber density needed for SR4 require a significant cable plant upgrade, making it expensive and disruptive for customers to migrate from 10-Gbps connectivity to 40‑Gbps connectivity in their existing data centers.

Solution with Cisco 40-Gbps QSFP BiDi Transceiver

The Cisco QSFP BiDi transceiver, shown in Figure 2, transmits full-duplex 40-Gbps traffic over one dual-fiber LC-connector OM3 or OM4 MMF cable. It provides the capability to reuse 10-Gbps fiber infrastructure. In other words, it enables data center operators to upgrade to 40-Gbps connectivity without making any changes to the previous 10-Gbps fiber cable plant.

The Cisco QSFP BiDi transceiver has two 20-Gbps channels, each transmitted and received simultaneously over two wavelengths on a single MMF strand. The result is an aggregated duplex 40-Gbps link over a MMF duplex LC-terminated fiber cable. The connection can reach 100 meters on OM3 MMF or 150 meters on OM4 MMF, which is the same as 40-Gbps SR4. Figure 3 shows the technology concept of the Cisco QSFP BiDi transceiver.

Most Cisco switching and routing products that support 40 Gigabit Ethernet interfaces support the Cisco QSFP BiDi transceiver. For a complete list of supporting products, refer to the Cisco 40 Gigabit Optical Transceiver product page at http://www.cisco.com/en/US/products/ps11708/index.html.

Savings with Cisco QSFP BiDi When Migrating from 10 Gbps to 40 Gbps

This section presents two case studies that demonstrate the savings achieved by using Cisco QSFP BiDi technology for 40-Gbps connectivity in data center networks. The case studies show how Cisco QSFP BiDi technology can remove the cost barriers for migrating and expanding the existing 10-Gbps cabling footprint to 40-Gbps infrastructure to provide the higher data rate in the data center network.

Case Study 1: 288 x 40-Gbps Connections with Unstructured Cabling

In an unstructured cabling system, devices are connected directly with fiber cables. This direct-attachment design can be used to connect devices within short distances in a data center network. As shown in Figure 4, direct connection between two 40-Gbps devices can be provided by MMF cables with either QSFP SR4 or QSFP BiDi transceivers at two ends.

The QSFP SR4 transceiver uses MPO-12 connectors, whereas Cisco QSFP BiDi uses LC connectors. Existing 10-Gbps connections commonly are MMF cables with LC connectors. Therefore, with QSFP SR4 transceivers, none of the existing 10-Gbps MMF cables can be reused because the connector types are different. Cisco QSFP BiDi allows cable reuse, resulting in zero-cost cabling migration from direct 10-Gbps connections to direct 40-Gbps connections.

Table 1 summarizes the costs and savings of migration and new deployment of 288 direct connections. To migrate the existing 288 10-Gbps connections to 40-Gbps connections, Cisco QSFP BiDi does not require any new spending on cables. Therefore, in comparison to QSFP SR4 transceivers, Cisco QSFP BiDi transceivers reduce costs by 100 percent and provide savings of up to US$290 per 40-Gbps port.

Table 1.       Fiber Infrastructure Savings for 10-Gbps to 40-Gbps Direct-Cabling Migration and New 40-Gbps Deployment

For the case in which 288 new direct 40-Gbps connections are needed in addition to the existing cabling infrastructure for a data center migration or expansion, the savings for 288 new connections using Cisco QSFP BiDi instead of QSFP SR4 transceivers is as high as 77 percent and US$221 per 40-Gbps port. These numbers do not take into account the installation costs. Adding installation costs could easily double the SR4 deployment costs.

Case Study 2: 384 x 40-Gbps Connections with Structured Cabling

A structured cabling system is commonly deployed in data center networks to provide flexible and scalable cabling infrastructure. Structured cabling uses short patch cords to attach devices to a patch panel and then runs fiber trunks either to consolidate the cables in a central location for additional connectivity or to direct them to another patch panel to which the remote devices are attached. Figure 5 shows a simple example of a 10-Gbps structured cabling design.

For migration of a data center with a structured 10-Gbps cabling system, Cisco QSFP BiDi technology allows you to repurpose the existing cabling system - including the patch cables, patch panels with MTP/MPO LC modules, and fiber trunks - for 40-Gbps connectivity. In contrast, QSFP SR4 transceivers require new patch cables and patch panels because the connector types differ and the size of the fiber trunk needs to be quadrupled.

This case study examines a simple nonblocking two-tier fabric design (Figure 6) that provides 1536 10-Gbps edge ports on its leaf layer. Its spine layer is composed of two Cisco Nexus 9508 Switches, and its leaf layer consists of 32 Cisco Nexus 9396PX Switches, each with six 40-Gbps links to every spine Cisco Nexus 9508. There are 384 40-Gbps links total between the leaf and spine layers.

If 384 x 10-Gbps connections are to be reused to construct this network, no additional spending on cabling will be needed if Cisco QSFP BiDi transceivers are used for all the 40-Gbps links. This scenario thus offers a 100 percent cost savings compared to the cost of reconstructing the cabling system using QSFP SR4 transceivers, including the cost of new patch cables, new patch panels, and expansion of the current fiber trunk.

If the cabling for this network is a new (greenfield) deployment or an expansion of an existing cabling system, the 384 x 40-Gbps connections can be built by using MMF cables and either QSFP SR4 transceivers or Cisco QSFP BiDi transceivers. Figures 7 and 8 show design examples for each option. Table 2 compares real-world cost estimates for these two designs. The design with Cisco QSFP BiDi offers 77 percent savings over that with QSFP SR4 transceivers, which is equivalent to a savings of US$2077 per 40-Gbps connection.

Table 2.       Structured 40-Gbps Cable Infrastructure Cost Comparison

Conclusion

Cisco QSFP BiDi technology removes 40-Gbps cabling cost barriers for migration from 10-Gbps to 40-Gbps connectivity in data center networks. Cisco QSFP BiDi transceivers provide 40-Gbps connectivity with immense savings and simplicity compared to other 40-Gbps QSFP transceivers. The Cisco QSFP BiDi transceiver allows organizations to migrate the existing 10-Gbps cabling infrastructure to 40 Gbps at no cost and to expand the infrastructure with low capital investment. Together with Cisco Nexus 9000 Series Switches, which introduce attractive pricing for networking devices, Cisco QSFP BiDi technology provides a cost-effective solution for migration from 10-Gbps to 40-Gbps infrastructure.

Direct Attach Cable assemblies are a high speed, cost-effective alternative to fiber optic cables in 10Gb Ethernet, 8Gb Fibre Channel and InfiniBand applications. They are suitable for short distances, making them ideal for highly cost-effective networking connectivity within a rack and between adjacent racks. They enable hardware OEMs and data center operators to achieve high port density and configurability at a low cost and reduced power requirement.

Compufox SFP+ copper cable assemblies meet the industry MSA for signal integrity performance. The cables are hot-removable and hot-insertable: You can remove and replace them without powering off the switch or disrupting switch functions. A cable comprises a low-voltage cable assembly that connects directly into two SFP+ ports, one at each end of the cable. The cables use high-performance integrated duplex serial data links for bidirectional communication and are designed for data rates of up to 10 Gbps.

Types of SFP+ Direct Attach Copper Cables

Applications of SFP+ Direct Attach Copper Cables

Compufox SFP+ Direct Attach Copper Cables Solution

Compufox SFP+ twinax copper cables are avaliable with custom version and brand compatible version. All of them are 100% compatible with major brands like Cisco, HP, Juniper, Enterasys, Extreme, H3C and so on. If you want to order high quality compatible SFP+ cables and get worldwide delivery, we are your best choice.

For instance, our compatible Cisco SFP+ Copper Twinax direct-attach cables are suitable for very short distances and offer a cost-effective way to connect within racks and across adjacent racks. We can provide both passive Twinax cables in lengths of 1, 3 and 5 meters, and active Twinax cables in lengths of 7 and 10 meters. (Tips: The lengths can be customized up to the customers' requirements.)

FAQ of Compufox SFP+ Direct Attach Copper Cables

Q: What are the performance requirements for the cable assembly?
A: Our SFP+ copper passive and active cable assemblies meet the signal integrity requirements defined by the industry MSA SFF-8431. We can custom engineer cable assemblies to meet the requirements of a customer’s specific system architecture.

Q: Are passive or active cable assemblies required?
A: Passive cables have no signal amplification in the assembly and rely on host system Electronic Dispersion Compensation (EDC) for signal amplification/equalization. Active cable assemblies have signal amplification and equalization built into the assembly. Active cable assemblies are typically used in host systems that do not employ EDC. This solution can be a cost savings to the customer.

Q: What wire gauge is required?
A: We offer SFP+ cable assemblies in wire gauges to support customers' specific cable routing requirements. Smaller wire gauges results in reduced weight, improved airflow and a more flexible cable for ease of routing.

Q: What cable lengths are required?
A: Cable length and wire gauge are related to the performance characteristics of the cable assembly. Longer cable lengths require heavier wire gauge, while shorter cable lengths can utilize a smaller gauge cable.

For all you SFP+ Direct attach cables, please see link below. We carry compatible cables for most major brands.

http://www.compufox.com/SFP_Cables_s/337.htm

Things you should Know Before Installing or Removing SFP

Before removing or installing a Transceiver Module you must disconnect all cables, because of leaving these attached will damage the cables, connectors, and the optical interfaces. At the same time please be aware that do not often remove and install an SFP transceiver and it can shorten its useful life. For this reason transceivers should not be removed or inserted more often than is required. Furthermore, transceiver modules are sensitive to static, so always ensure that you use an ESD wrist strap or comparable grounding device during both installation and removal.

Required Tools

Installing SFP Transceiver Modules

Determine which type of latch your SFP transceiver uses before following the installation and removal procedures.

To install an SFP transceiver, follow these steps:

Step 1. Attach an ESD-preventive wrist strap to your wrist and to the ESD ground connector or a bare metal surface on your chassis.

Step 2. Remove the SFP Transceiver Module from its protective packaging.

Note: Do not remove the optical bore dust plugs until directed to do so later in the procedure.

Step 3. Check the label on the SFP transceiver body to verify that you have the correct model for your network.

Step 4. Find the send (TX) and receive (RX) markings that identify the top side of the SFP transceiver.

Note: On some SFP transceivers, the TX and RX marking might be replaced by arrowheads that point from the SFP transceiver connector (transmit direction or TX) and toward the connector (receive direction or RX).

Step 5. Position the SFP transceiver in front of the socket opening.

Note: Different Cisco devices have different SFP module socket configurations. Your Cisco device could have either a latch-up or a latch-down orientation. Ensure that you are installing the SFP transceiver in the correct orientation for your Cisco device. Refer to the hardware installation instructions that came with your Cisco device for more details.

Step 6. Insert the SFP transceiver into the socket until you feel the SFP Transceiver Module connector snap into place in the socket connector.

Note: For optical SFP transceivers, before you remove the dust plugs and make any optical connections, observe these guidelines:
a. Always keep the protective dust plugs on the unplugged fiber-optic cable connectors and the transceiver optical bores until you are ready to make a connection.
b. Always inspect and clean the LC connector end-faces just before you make any connections. See the Required Tools section of this document for more information.
c. Always grasp the LC connector housing to plug or unplug a fiber-optic cable.

Step 7. Remove the dust plugs from the network interface cable LC connectors. Save the dust plugs for future use.

Step 8. Inspect and clean the LC connector’s fiber-optic end-faces.

Step 9. Remove the dust plugs from the SFP transceiver optical bores.

Step 10. Immediately attach the network interface cable LC connector to the SFP transceiver.

Step 11. Connect the 1000BASE-T SFP transceivers to a copper network.

Caution: In order to comply with GR-1089 intrabuilding lightning immunity requirements, you must use grounded, shielded, twisted-pair Category 5 cabling.

Complete these steps in order to connect the transceivers to a copper network:
a.Insert the Category 5 network cable RJ-45 connector into the SFP transceiver RJ-45 connector.

Note: When you connect to a 1000BASE-T-compatible server, workstation, or router, use four twisted-pair, straight-through Category 5 cabling for the SFP transceiver port. When you connect to a 1000BASE-T-compatible switch or repeater, use four twisted-pair, crossover Category 5 cabling.

b.Insert the other end of the network cable into an RJ-45 connector on a 1000BASE-T-compatible target device.
c. Reconfigure and reboot the target device if necessary.

Step 12. Observe the port status LED:
a. The LED turns green when the SFP transceiver and the target device have an established link.
b. The LED turns amber while STP discovers the network topology and searches for loops. This process takes about 30 seconds, and then the LED turns green.
c. If the LED is off, the target device might not be turned on, there might be a cable problem, or there might be a problem with the adapter installed in the target device. Refer to the Troubleshooting section of your switch hardware guide for solutions to cabling problems.

Removing SFP Transceiver Modules

Step 1. Attach an ESD-preventive wrist strap to your wrist and to the ESD ground connector or a bare metal surface on your chassis.

Step 2. Disconnect the network fiber-optic cable or network copper cable from the SFP Transceiver Module connector. For optical SFP transceivers, immediately reinstall the dust plugs in the SFP transceiver optical bores and the fiber-optic cable LC connectors.

Tips: For reattachment of fiber-optic cables, note which connector plug is send (TX) and which is receive (RX).

Step 3. Release and remove the SFP Transceiver Module from the socket connector.
a. If the SFP transceiver has a Mylar tab latch, pull the tab gently in a slightly downward direction until the transceiver disengages from the socket connector, and then pull the SFP transceiver straight out. Do not twist or pull the Mylar tab because you could detach it from the SFP transceiver.

b. If the SFP transceiver has an Actuator button latch, gently press the actuator button on the front of the SFP transceiver until it clicks and the latch mechanism releases the SFP transceiver from the socket connector. Grasp the actuator button between your thumb and index finger, and carefully pull the SFP transceiver straight from the module slot.

c. If the SFP transceiver has a Bale-clasp latch, pull the bale out and down to eject the SFP transceiver from the socket connector. If the bale-clasp latch is obstructed and you cannot use your index finger to open it, use a small flat-blade screwdriver or another long narrow instrument to open the bale-clasp latch. Grasp the SFP transceiver between your thumb and index finger, and carefully remove it from the socket.

Step 4. Place the removed SFP transceiver in an antistatic bag or other protective environment.

To purchase Cisco compatible SFP transceivers, click on the Link below:

• SFP

Key Factors Influencing Your Decision

Firstly, there are some key factors which will influence your decision. Thus, you must make sure that what your network really requires. As we mentioned above, an SAN has server, storage device and switches. So, what should we consider in every section of the network?

• Server to Switch Connectivity Solution

• Storage to Switch Connectivity Solution

• Switch to Switch Connectivity Solution

 COMPUFOX Solutions

COMPUFOX  offers a comprehensive solution of optics and cables which supports your network from 1GbE to 100GbE. We have a great selection of 1000BASE-T/SX/LX SFP, BiDi SFP, 10GBASE-SR/LR SFP+, DWDM SFP+, whole series 40G QSFP+ optics and cables, as well as the 100G CFP2 and CFP4, etc. which help you solve the cost issue in fiber project. Especially the 40G QSFP+ optics, with the passive optic design, they can be compatible with all the equipment of all major brands. In addition, most of them are ready stock. See Links below:

• CFP
• CWDM
• DWDM
• GBIC
• QSFP+
• SFP+
• SFP
• X2
• XENPAK
• XFP
• QSFP+ Cables
• QSFP+ to 4 SFP+ Cables
• QSFP+ to 4 XFP Cables
• QSFP+ to 4 LC Cables
• QSFP+ to CX4 Cables
• SFP Cables
• SFP+ Cables
• SFP+ to XFP Cables

What's BiDi Transceiver?

BiDi transceiver is a type of fiber optic transceivers which is used WDM (Wavelength Division Multiplexing) Bi-directional transmission technology so that it can achieve the transmission of optical channels on a fiber propagating simultaneously in both directions. BiDi transceiver is only with one port which uses an integral bidirectional coupler to transmit and receive signals over a single fiber optical cable. Thus, it must be used in pairs.

How Does BiDi Transceiver Work

The primary difference between BiDi transceivers and traditional two-fiber fiber optic transceivers is that BiDi transceivers are fitted with Wavelength Division Multiplexing (WDM) couplers, also known as diplexers, which combine and separate data transmitted over a single fiber based on the wavelengths of the light. For this reason, BiDi transceivers are also referred to as WDM transceivers.

To work effectively, BiDi transceivers must be deployed in matched pairs, with their diplexers tuned to match the expected wavelength of the transmitter and receiver that they will be transmitting data from or to.

For example, if paired BiDi transceivers are being used to connect Device A (Upstream) and Device B (Downstream), as shown in the figure below, then:

Advantages of BiDi Transceivers

The obvious advantage of utilizing BiDi transceivers, such as SFP+- BiDi and SFP-BiDi transceivers, is the reduction in fiber cabling infrastructure costs by reducing the number of fiber patch panel ports, reducing the amount of tray space dedicated to fiber management, and requiring less fiber cable.

While BiDi transceivers (a.k.a. WDM transceivers) cost more to initially purchase than traditional two-fiber transceivers, they utilize half the amount of fiber per unit of distance. For many networks, the cost savings of utilizing less fiber is enough to more than offset the higher purchase price of BiDi transceivers.

40GbE QSFP+ Transceivers Overview

40 Gigabit Ethernet (40GbE) aggregation switches are becoming more common in today's data centers. At the heart of the 40GbE network layer is a pair of transceivers connected by a cable. The transceivers are plugged into either network servers or a variety of components including interface cards and switches and connected via the cables such as OM3 and OM4 for multimode application. Additionally DAC (Direct Attach Copper) cables or AOCs (Active Optical Cables) are used for short interconnection as a more cost-effective alternative solution. QSFP+ (Quad Small Form-factor Pluggable Plus) is the most common 40GbE interface type, and also as a high-density 10GbE interface via QSFP+ breakout cables. QSFP+ interfaces a network device (switch, router, media converter or similar device) to a fiber optic or copper cable, supporting data rates from 4x10 Gbps and supports Ethernet, Fibre Channel, InfiniBand and SONET/SDH standards with different data rate options. Compared to CFP (C form-factor pluggable) transceiver modules, QSFP transceiver modules are more compact and more suitable for port-density application. The two basic interface specifications of QSFP+ modules respectively for multimode and single-mode applications are 40GBASE-SR4 and 40GBASE-LR4.

The 40GBASE-SR4 QSFP+ module, conforming to the 802.3ba D3.2 (40GBASE-SR4) standard, provides a 40Gbps optical connection using MPO/MTP® optical connectors. This optical module integrates four data lanes in each direction with 40Gbps aggregate bandwidth and each lane can operate at 10.3125 Gbps. It is used in data centers to interconnect two Ethernet switches with 8 fiber parallel multimode fiber OM3/OM4 cables (transmission distance can be up to 100 meters using OM3 fiber or up to 150 meters using OM4 fiber).

The 40GBBASE-LR4 QSFP+ module, conforming to the 802.3ba (40GBASE-LR4) standard, provides a 40Gbps optical connection using LC optical connectors. This optical module integrates four data lanes in each direction with 40Gbps aggregate bandwidth and each lane can operate at 10.3125 Gbps. It is most commonly deployed between data center or IXP sites with single-mode fiber up to 10 km.

 In addition, to satisfy a number of different objectives including support for MMF and SMF compatibility, there are other types of QSFP+ modules offered by different vendors.

To protect a QSFP+ module or cable from ESD (electro-static discharge) damage, before installing or removing a QSFP+ module or cable, be remembered that always wear an ESD wrist strap and make sure that it makes good skin contact and is securely grounded (If you are using ESD gloves, wear the wrist strap outside the ESD glove).

There are two types of clasp designed for a QSFP+ transceiver module—plastic clasp or a metallic clasp. Here uses the metallic clasp type as an example.

Step 1. Remove the QSFP+ module from its antistatic container and remove the dust covers from the module optical connector.
Step 2. Remove any rubber dust covers from the port where you are installing the QSFP+ module.
Step 3. Pivot the clasp of the module up. (Skip this step if the clasp is plastic.)
Step 4. Align the module with the port in the chassis, as shown in Figure 1.

Figure 1. Aligning the module with the port

Step 5. Holding the module, gently push in the module until it is firmly seated in the port.(see Figure 2.)

Figure 2. Install the QSFP+ module to port

Step 6. Immediately attach the patch cord with MPO connector or duplex LC connector to the QSFP+ transceiver module.(see Figure 3.)

Figure 3. Install the patch cord to the module

Note: Install the dust plug for the transceiver module if you are not to install an optical fiber into it.

Step 1. Remove the optical fiber if any.
Step 2. Pivot the clasp of the module down to the horizontal position. (Skip this step if the clasp is plastic.)
Step 3. Holding the module, gently pull the module out of the port. (Figure 4)
Step 4. Place the QSFP+ transceiver into an antistatic bag.

Figure 4. Remove the QSFP+ module

The installation and removal procedures are the same for QSFP+ DAC cables and QSFP+ AOC cables. Here uses a QSFP+ DAC cable as an example:

Step 1. Align the QSFP+ transceiver module (with the clasp on top) at one end of the cable with the port in the chassis, as shown in Figure 5.
Step 2. Horizontally and gently push in the module to fully seat it in the port.

Figure 5. Installing a QSFP+ DAC cable

Step 1. Gently press and release the QSFP+ transceiver module.(see Figure 6.)
Step 2. Holding the cable, gently pull the clasp on the cable to pull out the transceiver module.

Figure 6. Removing a QSFP+ DAC cable

40G QSFP+ to 4x10G SFP+ cable combines one 40G QSFP+ module on one end and four 10G SFP+ module on the other end. The installation and removal procedures of 40G QSFP+ connector are introdueced above. Here only introduced the installation and removal of 10G SFP+ module:

Step 1. Align the module with the SFP+ port, with the golden plating facing the spring tab (see Figure 7.) in the SFP+ port. If the chassis has two rows of ports, the spring tab in a port is on the bottom in the upper row and on the top in the lower row.
Step 2. Slightly press the module against the spring tab so you can push the module straight into the port.

Figure 7. Installing an SFP+ transceiver module

Step 1. Press the module with your thumb, as shown by callout 1 in Figure 8.
Step 2. Gently pull the clasp on the cable to pull out the transceiver module, as shown by callout 2 in Figure 8.

Figure 8. Removing an SFP+ transceiver module

Verifying the installation

Execute the display transceiver interface command on the device to verify that the transceiver module or DAC/AOC cable is installed correctly. If the transceiver module and DAC/AOC cable information is displayed correctly, the installation is correct. If an error message is displayed, the installation is incorrect or the transceiver optics is not compatible.

Conclusion

As 40 GbE are widely deployed, 40G transceiver optics are ubiquitous. A good practice and correct installation are very important for 40G network system, not only to protect the 40G transceiver optics and device from damage, but also to ensure a stable performance for system. In addition, by executing the display transceiver interface command, we can verify whether the installation is correct. Of course, the premise is that the transceiver optics you use is fully compatible with your device. COMPUFOX offers a comprehensive line of high-compatible 40G transceiver optics, such as 40GBASE-SR4 QSFP+, 40GBASE-LR4 QSFP+ and 40G DACs and AOCs with competitive prices. See Links below:

• QSFP+
  
• QSFP+ Cables
• QSFP+ to 4 SFP+ Cables
• QSFP+ to 4 XFP Cables
• QSFP+ to 4 LC Cables
• QSFP+ to CX4 Cables