A Brief Introduction to Cisco Single-Mode SFP Modules

Introduction

Small form-factor pluggable (SFP) module is a hot-pluggable interface transceiver which links switches and routers to network. These small, modular optical interface transceivers offer a convenient and cost effective solution for the adoption of Gigabit Ethernet and Fibre Channel in data center. Cisco’s industry-standard SFPs can be used and interchanged on a wide variety of Cisco products and can be intermixed in combinations of IEEE 802.3z compliant 1000BaseSX, 1000BaseLX/LH, or 1000BaseZX interfaces on a port-by-port basis. Cisco SFP modules are commonly available in several different types: 1000BASE-T, 1000BASE-SX, 1000BASE-LX/LH, 1000BASE-EX, 1000BASE-ZX, and 1000BASE-BX-D/U. This post will give an introduction to Cisco single-mode SFP modules.

Cisco 1G single-mode SFP

Cisco 1G Single-Mode SFP Modules

Cisco 1G single-mode SFP modules consist of 1000BASE-LX/LH, 1000BASE-EX, 1000BASE-ZX, 1000BASE-BX-U, 1000BASE-BX-D, GLC-BX40-D-I, GLC-BX40-DA-I, GLC-BX40-U-I, GLC-BX80-D-I, and GLC-BX80-U-I. The 1000BASE-LX/LH SFP is compatible with the IEEE 802.3z 1000BASE-LX standard, functions on single-mode fiber-optic link and its transmission range can cover 550 m to 10 km on any multimode fibers. 1000BASE-EX SFP functions on standard single-mode fiber-optic link with spanning up to 40 km in length. 1000BASE-ZX SFP functions on standard single-mode fiber-optic link and its transmission range reaches approximately 70 km in length.

The 1000BASE-BX-D and 1000BASE-BX-U SFPs which are compatible with the IEEE 802.3ah 1000BASE-BX10-D and 1000BASE-BX10-U standards function on a single strand of standard SMF (Single-Mode Fiber) and its operating transmission range covers up to 10 km. The Cisco GLC-BX40-D-I, GLC-BX40-DA-I, and GLC-BX40-U-I SFPs also operate on a single strand of standard SMF and its transmission range can reach 40 km. A GLC-BX80-D-I and GLC-BX80-U-I device function on a single strand of standard SMF with an operating transmission range up to 80 km.

Another difference between these SFP modules is the transmission direction: 1000BASE-LX/LH, 1000BASE-EX and 1000BASE-ZX’ transmission is duplex while 1000BASE-BX-U, 1000BASE-BX-D, GLC-BX40-D-I, GLC-BX40-DA-I, GLC-BX40-U-I, GLC-BX80-D-I, and GLC-BX80-U-I’s transmission is simplex. One thing they have in common is that all these Cisco single-mode SFP modules adopt LC interfaces and Cisco SFP 1G transceivers can transmit optical signals through simplex or duplex LC patch cable.

Transmission of a Single Strand of SMF

Features and Benefits

Cisco single-mode SFP modules feature a variety of different types of modules supporting different transmission ranges and direction, and they are also compatible with products of other categories. The hot-swappable input/output device directly plugs into an Ethernet SFP port of a Cisco switch, which maximizes uptime and simplifies serviceability when installing or replacing. The robust design enhances capability and the small factor features great density per chassis. Its flexibility of media and interface choice on a port-by-port basis bring you convenience. “Pay as you Populate” model lowers initial costs. It can support digital optical monitoring (DOM) capability for strong diagnostic capabilities. Cisco quality identification (ID) feature enables a Cisco platform to identify whether the module is certified and tested by Cisco and it can be interoperable with other IEEE-compliant 1000BASE interfaces where applicable.

Conclusion

This post briefly introduces Cisco single-mode SFP modules, covering its definition, types of these SFPs and introduction of each type, and features and benefits of Cisco single-mode SFP modules. Now there are a number of modules for you to choose, but be sure to find the right one based just on your needs and at the same time take a few factors into consideration.

Classification Guide to Fiber Optical Module

Owing to the rapid progresses made in fiber optical technology, more and more networking infrastructure installations and upgrades choose fiber optic links for high-data-rate transmission. There is no question that compared with copper solutions, fiber optics provides greater bandwidth, more reliable data transmission, and immunity to electromagnetic interference and radio-frequency interference (EMI/RFI), crosstalk, impedance problems, and more. For constituting such fiber optic links, fiber optic module, one of the fast-growing transmission components, are instrumental, and work well in these applications where high-bandwidth and long-distance transmission are needed.

Along with the fiber optical technology advances, fiber optic module has been constantly designed and reinnovated, so as to better facilitate electrical-optical-electrical signal conversion. They are classified into several categories according to different standards regarding package, transmission mode, data rate and power supply. This text will talk about every classification standard in details.

Based-on Different Package Standard

MSAs (Multi-Source Agreements) are agreements between multiple manufacturers, system integrators, and suppliers, specifying parameters for system components and their guideline values, such as the electrical and optical interfaces, mechanical dimensions and electro-magnetic values. The equipment vendors follow these MSA defined values for designing their systems to ensure interoperability between interface modules. The form-factor or the MSA-type is needed so that the transceiver can mechanically and electrically fit into a given switch, router, etc. Transceiver MSAs define mechanical form factors including electric interface as well as power consumption and cable connector types. There are various MSA types: SFP (eg. E1MG-TX), SFP+, QSFP and so on.

fiber optical modules

By Transmission Mode Standard

When talking about this standard, single mode optical modules and multi-mode optical modules come to the central point.

  • Single Mode Fiber Optic Module

Single-mode optical modules, or single-mode transceivers, just as their name show, are designed to work over single mode fibers (SMFs). Compared with multimode fiber (MMF), SMF fiber core is smaller and the wavelength of the laser is narrower, meaning that while transmitting optical signals, SMF is able to deliver higher bandwidth at the much longer distances, like 2km, 10km, 40km, 60km, 80km and 120km transmission. Commonly-seen single-mode transceiver types include 10GBASE-LR, 1000BASE-LR, 1000BASE-BX, etc..

  • Multimode Fiber Optic Module

Multimode optical modules, or multimode transceivers, operate over MMF which uses a much bigger core and usually uses a longer wavelength of light. Thus, the optics used in MMF has a higher capability to gather light from the laser, for short distance transmission, with distance reach ranging from 100m to 500m. 10GBASE-SR is one of the most widely-used multi-mode transceiver types, such as AFBR-703SDZ-IN2. This Avago Intel compatible 10GBASE-SR SFP+ transceiver listed in FS.COM works over MMF with 850nm laser light for 300m distance reach.

AFBR-703SDZ-IN2, 10GBASE-SR SFP+ fiber optic module

According to Data Rate & Power Supply Standard
  • The connection between two network devices is realized with the help of protocols. It is imperative to know which protocol and data rate the switch or router supports. There are various protocols such as Ethernet, Fiber Channel (FC), InfiniBand, SONET/SDH, CPRI and so on. Each of these protocols supports their own data rates. For example Gigabit Ethernet (GbE) can range from 1Gb/s to 100Gb/s, while FC ranges from 1GFC (1.0625Gb/s) to 16GFC (14.025Gb/s).
  • As for power supply, there are built-in switching power transceiver and eternal power supply transceiver. The built-in switching power transceiver is designed for the carrier grade power. It supports equipment power protection, filters, and a wide power supply voltage regulator, reducing the external point of failure arising from the mechanical contact. By contrast,the external power supply transceiver is made for multi-use civilian equipment, and it is compact and cheap.
  • Of course, the classification standards of fiber optic module is not limited to those three points mentioned above. Other standards are also workable, such as the network management standard. It’s known that there are managed optical modules and unmanaged optical modules. The former type allows additional network monitoring with fault detection, free from configuration function. By contrast, the latter, without monitoring function, allows automatic communication of the devices that are connected to unmanaged optical modules.
Conclusion

When your networking projects call for fiber optic module for fiber optic links, these classification standards will work, since they help you to choose the right fiber optic modules for applications to ensure the reliable data transmission. FS.COM offers an ocean of fiber optic modules which are fully compatible with major brands, including the Brocade E1MGTX, and Avago Intel AFBR-703SDZ-IN2 mentioned above.

10GbE Interconnect Solutions Overview

New sophisticated networking services, coupled with the increase of Internet users push the Internet traffic to an even higher point, driving the need for increased bandwidth consequently. One Ethernet technology—10 Gigabit Ethernet (GbE) is adequate for such bandwidth demand, and has become widely available due to the competitive price and performance, as well as its simplified cabling structure.

Several cable and interconnect solutions are available for 10GbE, the choice of which depends on the maximum interconnect distance, power budget and heat consumption, signal latency, network reliability, component adaptability to future requirements, cost. Here cost includes more than what we call the equipment interface and cable cost, but more often the labor cost. Thus, choosing a 10GbE interconnect solution requires careful evaluation of each option against the specific applications. This text aims to introduce two main 10GbE interconnect solutions: fiber optics and copper.

Fiber Optics Solution

Fiber optic cables include single-mode fiber (SMF) and multi-mode fiber (MMF). MMF is larger in diameter than that of single-mode, thus portions of the light beam follow different paths as they bounce back and forth between the walls of the fiber, leading to the possible distorted signal when reach the other end of the cable. The amount of distortion increases with the length of the cable. The light beam follows a single path through thinner single-mode cable, so the amount of distortion is much lower.

fiber optics solution: SMF & MMF

The typical 10GBASE port type that uses MMF is 10GBASE-SR which uses 850nm lasers. When used with OM3 MMF, 10GBASE-SR can support 300m-connection distances, and when with OM4 MMF, 400m link length is possible through 10GBASE-SR SFP+ transceiver.

10GBASE-LR (eg. E10GSFPLR), 10GBASE-ER and 10GBASE-ZR are all specified to work via SMF. SMF can carry signals up to 80km, so it is more often used in wide-area networks. But since SMF requires a more expensive laser light source than MMF does, SMF is replaced by MMF when the required connection distance is not so long.

Copper Solution

10GBASE-CX4, SFP+ Direct Attach (DAC) and 10GBASE-T are all specified to operate through copper medium.

  • 10GBASE-CX4

Being the first 10GbE copper solution standardized by the IEEE as 802.3ak in 2002, 10GBase-CX4 uses four cables, each carrying 2.5gigabits of data. It is specified to work up to a distance of 15m. Although 10GBase-CX4 provides an extremely cost-effective method to connect equipment within that 15m-distance, its bulky weight and big size of the CX4 connector prohibited higher switch densities required for large scale deployment. Besides, large diameter cables are purchased in fixed lengths, causing problems in managing cable slack. What’s more, the space isn’t sufficient enough to handle these large cables.

  • SFP+ DAC

SFP+ Direct Attach Cable (DAC), or called 10GSFP+Cu, is a copper 10GBASE twin-axial cable, connected directly into an SFP+ housing. It comes in either an active or passive twin-axial cable assembly. This solution provides a low-cost and low energy-consuming interconnect with a flexible cabling length, typically 1 to 7m (passive versions) or up to 15m (active versions) in length. Below is the SFP+ to SFP+ passive copper cable assembly with 1m length, 487655-B21, a HP compatible 10GbE cabling product.

SFP+ to SFP+ passive copper cable assembly, 1m link length

  • 10GBASE-T

10GBASE-T, known as IEEE 802.3an-2006, utilizes twisted pair cables and RJ-45 connectors over distances up to 100m. Cat 6 and Cat 6a are recommended, with the former reaching the full length at 100m, and the latter at 55m. In a word, 10GBASE-T permits operations over 4-connector structured 4-pair twisted-pair copper cabling for all supported distances within 100m. Besides, 10GBASE-T cabling solution is backward-compatible with 1000BASE-T switch infrastructures, keeping costs down while offering an easy migration path from 1GbE to 10GbE.

Conclusion

In summary, two main media options are available for 10GbE interconnect: copper and fiber optics, including 10GBASE-CX4, SFP+ DAC, 10GBASE-T, 10GBASE-SR, 10GBASE-LR, 10GBASE-ER, 10GBASE-ZR, and so on. Fiberstore offers all these 10GBASE SFP+ modules and cables for your 10GbE deployment, which are quality-assured and cost-effective, like E10GSFPLR and 487655-B21 mentioned above. For more information about 10GbE interconnect solutions, you can visit Fiberstore.

1000BASE-X SFP Modules Overview

A continuous stream of manufacturing process improvements and product innovations has given fiber optical system several advantages, like longer distance reach, larger data-carrying capacity, greater bandwidth and lower power consumption. Among these fiber optical product innovations, hot-pluggable 1000BASE-X transceiver modules should come to the central point with their unique designs. They have been constantly designed, and finally been reinvented as hot-pluggable modules along with the optical technological advances. These small, hot-pluggable serve as the key components in accommodating the demands of higher port density and more networking flexibility.

Transceiver module comes into various types: SFP (small form-factor pluggable), SFP+ (small form-factor pluggable plus), QSFP+ (quad small form-factor pluggable plus), etc. This article mainly introduces SFP transceiver modules which are widely applied in Gigabit Ethernet (GbE) applications, with the focus on several 1000BASE-X interface types, including 1000BASE-SX, 1000BASE-LX, 1000BASE-EX, and 1000BASE-BX10-D/U.

Features and Benefits

1000BASE-X SFP modules provide a wide range of form factor options for enterprise and service provider needs. They are designed with the following features and benefits:

  • Hot swappable to maximize uptime and simplify serviceability;
  • Flexibility of media and interface choice on a port-by-port basis, so you can “pay as you populate”;
  • Sophisticated design for enhanced reliability;
  • Supports digital optical monitoring (DOM) function;
1000BASE-X SFP Interface Types

1000BASE-SX SFP

1000BASE-SX SFP, compatible with the IEEE 802.3z 1000BASE-SX standard, operates on legacy 50μm multi-mode fiber (MMF) links up to 550m and on 62.5μm Fiber Distributed Data Interface (FDDI)-grade MMFs up to 220m. Take DEM-311GT for example, Fiberstore compatible D-Link 1000BASE-SX SFP is able to realize 550m link length through OM2 MMF with duplex LC.

DEM-311GT, D-Link 1000BASE-SX SFP

1000BASE-LX SFP

1000BASE-LX SFP, compatible with the IEEE 802.3z 1000BASE-LX standard, is specified to support link length of up to 10km on standard single-mode fiber (SMF), to 550m on MMFs. When used over legacy MMF, the transmitter should be coupled through a mode conditioning patch cable. The laser is launched at a precise offset from the center of the fiber which causes it to spread across the diameter of the fiber core, reducing the effect known as differential mode delay which occurs when the laser couples onto only a small number of available modes in MMF.

1000BASE-EX SFP

1000BASE-EX, sometimes referred to as LH, is a non-standard but industry accepted standard which works on standard SMF with fiber link spans up to 40km in length. For back-to-back connectivity, a 5-dB inline optical attenuator should be inserted between the fiber optic cable and the receiving port on the SFP at each end of the link. 1000BASE-EX SFPs (eg. GLC-EX-SMD) run on 1310nm wavelength lasers, and achieves 40km link length.

1000BASE-BX10-D/U SFP

The 1000BASE-BX-D and 1000BASE-BX-U SFPs, compatible with the IEEE 802.3ah 1000BASE-BX10-D and 1000BASE-BX10-U standards, operate on a single strand of standard SMF (figure shown below). A 1000BASE-BX10-D device is always connected to a 1000BASE-BX10-U device by a single strand of standard SMF with an operating transmission distance up to 10km.

1000BASE-X

The communication over a single strand of fiber is accomplished by separating the transmission wavelength of the two devices (figure shown above): 1000BASE-BX10-D transmits a 1490nm channel and receives a 1310nm signal, whereas 1000BASE-BX10-U transmits at a 1310-nm wavelength and receives a 1490-nm signal. In this figure, the wavelength-division multiplexing (WDM) splitter is integrated into the SFP to split the 1310nm and 1490nm light paths.

Conclusion

These 1000BASE-X SFP modules provide physical layer connectivity for optical-port modular switch IO blades and optical-port stackable switches, reliable, and cost-effective choices to accommodate varied and evolving network demands. As a professional fiber optic product manufacturer and supplier, Fiberstore supplies all the above-mentioned several 1000BASE-X SFP modules which are all test- and quality-assured. You can visit Fiberstore for more information about 1000BASE-X SFP modules.

Related Article:Introduction to Single Strand Fiber Solution

Transceiver Module Selection Guide for Your Networking Use

Thanks to the advances made in fiber optical technologies, fiber solutions have been deployed in ever-increasing applications where high-speed and high-performance data transmission is needed. They outweigh the copper solutions in such aspects as higher bandwidth, longer distances and Electromagnetic interference (EMI) immunity. Transceiver module, one of the key components required in such fiber connections for high networking performance, have experienced the never-ceasing industrial designs, from lower port density to higher, from the standard modules to the final hot-pluggable ones, to meet the ever more flexible networking infrastructure.

There is a broad selection of hot-pluggable transceiver modules available for fiber networking use, and you may feel a little confused about how to select the correct transceiver module for your networking transmission. In this article, I will illustrate different aspects of transceivers that need to be known before choosing a transceiver.

Transceiver Module Basics

Before giving guidance to transceiver selection, it’s necessary to know the basics of transceiver. Transceiver is a combination of a transmitter and a receiver in a single package, while they function independently for bidirectional communication. Typically, a fiber optic transceiver converts the incoming optical signal to electrical and the outgoing electrical signal to optical. More specifically, the transmitter takes an electrical input and converts it to an optical output from a laser diode or LED. The light from the transmitter is coupled into the fiber with a connector and is transmitted through the fiber optic cable plant. The light from the end of the fiber is coupled to a receiver where a detector converts the light into an electrical signal which is then conditioned properly for use by the receiving equipment.

Here go the several aspects of transceiver modules that are helpful in your purchasing.

Form-factorseveral MSA transceiver module types

Multi-source agreements (MSAs) between different equipment vendors specify guidelines for electrical and optical interfaces, mechanical dimensions and electro-magnetic specification of a transceiver module. The equipment vendors follow these MSA defined values for designing their systems to ensure interoperability between interface modules. The form-factor or the MSA-type is needed so that the transceiver can mechanically and electrically fit into a given switch, router, etc. Transceiver MSAs define mechanical form factors including electric interface as well as power consumption and cable connector types. There are various MSA types: SFP (eg. MGBSX1), SFP+, XFP, CFP, CFP2, CFP4, QSFP and so on.

Transmission Media

Transceivers can work over single-mode fiber (SMF), multi-mode fiber (MMF), and copper. In different Ethernet applications, media can achieve different link lengths when combined with transceivers. Take Gigabit Ethernet (GbE) applications for example, single mode SFP transceivers can have a transmission distance of 5km to 120km, while multimode SFP transceivers are defined to have the maximum reach of 55om, with copper solution establishing even fewer link length at 25m. Take MGBLX1 for example, this Cisco compatible 1000BASE-LX SFP works through SMF for 10km reach.

Power Budget

The transceiver power budget is the difference between transmitter launch power and receiver sensitivity and has to be 2-3dB larger (Margin) than the measured link loss. If the link loss cannot be measured, it has to be calculated. Therefore transmission distance [km], the number of ODFs, patches and passive optical components (Muxes) have to be known. Common values for power budget are <10, 14, 20, 24, 28, >30dB.

power budget

If you’re seeking high-speed data carrier, transceivers can help accomplish goals. By transmitting data at 10Gbit/s, 40Gbit/s, 100Gbit/s or 12940Gbit/s, they can ensure that data arrives quickly. Transceiver modules that are capable of handling fast speeds can help with downloads and high and low bandwidth video transmission.

Conclusion

Transceiver modules are instrumental in ensuring that the data is transmitted securely, expeditiously, and accurately across the media. Choosing the right type of transceiver for your network is not always easy, but knowing above discussed parameters beforehand helps you narrow it down to a few transceivers. FS.COM offers a sea of transceiver modules which are fully compatible with major brands, like the above mentioned MGBSX1 and MGBLX1, the Cisco compatible transceiver modules.

Considerations About Optical Transceiver Designing

The rapid expansion of fiber optic networks, including data services measured by data volume or bandwidth, shows that fiber optic transmission technology is and will continue to be a significant part of future networking systems. Network designers are becoming increasingly comfortable with fiber solutions, since the use of which allows for more flexible network architecture and other advantages, such as EMI (Electromagnetic Interference) resilience and data security. Optical transceiver plays an really important role in these fiber connections. And while designing fiber optic transceivers, three aspects need to be considered: environmental situation, electrical condition and optical performance.

What Is a Optical Transceiver?

The optical transceiver is a self-contained component that transmits and receives signals. Usually, it is inserted in devices such as routers or network interface cards which provide one or more transceiver module slot. The transmitter takes an electrical input and converts it to an optical output from a laser diode or LED. The light from the transmitter is coupled into the fiber with a connector and is transmitted through the fiber optic cable plant. Then the light from the end of the fiber is coupled to a receiver where a detector converts the light into an electrical signal which is then conditioned properly for use by the receiving equipment. There are a full range of optical transceivers available in telecommunication market, like SFP transceiver, SFP+ transceiver (eg. SFP-10G-SR shown below), 40G QSFP+, 100G CFP, etc.SFP-10G-SR optical transceiver

Optical Transceiver Designing Considerations

It’s true that fiber links can handle higher data rates over longer distances than copper solutions, which drive the even wider use of optical transceivers. While designing fiber optic transceivers, the following aspects should be taken into consideration.

  • Environmental Situation

One challenge comes to the outside weather—especially severe weather at elevated or exposed heights. The components must operate over extreme environmental conditions, over a wider temperature range. The second environmental issue related to the optical transceiver design is the host board environment which contains the system power dissipation and thermal dissipation characteristics.

A major advantage of the fiber optic transceiver is the relatively low electrical power requirements. However, this low power does not exactly mean that the thermal design can be ignored when assembling a host configuration. Sufficient ventilation or airflow should be included to help dissipate thermal energy that is drawn off the module. Part of this requirement is addressed by the standardized SFP cage which is mounted on the host board and also serves as a conduit for thermal energy. Case temperature reported by the Digital Monitor Interface (DMI), when the host operates at its maximum design temperature, is the ultimate test of the effectiveness of the overall system thermal design.

  • Electrical Condition

Essentially, the fiber transceiver is an electrical device. In order to maintain error free performance for the data passing through the module, the power supply to the module must be stable and noise-free. What’s more, the power supply driving the transceiver must be appropriately filtered. The typical filters have been specified in the Multisource Agreements (MSAs) which have guided the original designs for these transceivers. One such design in the SFF-8431 specification is shown below.

filter

  • Optical Performance

Optical performance is measured as Bit Error Rate, or BER. The problem facing designing optical transceiver lie in the case that the optical parameters for the transmitter and receiver have to be controlled, so that any possible degradation of the optical signal while traveling along the fibers will not cause poor BER performance. The primary parameter of relevance is the BER of the complete link. That is, the start of the link is the source of the electrical signals which drive the transmitter, and at the end, the electrical signal is received and interpreted by the circuitry in the host by the receiver. For those communication links which use optical transceivers, the primary goal is to guarantee BER performance at different link distances, and to ensure broad interoperability with third party transceivers from different vendors.

Conclusion

Fiber technology is becoming maturer, leading to the wider use of optical transceivers. With the three aspects mentioned above in mind, designing fiber optic transceivers should be easier. FS.COM supplies many transceivers which are fully compatible with major brands, including HP compatible transceivers (eg. J4858C).

Two Main Questions About Direct Attach Cables

The increasing bandwidth demands in data centers call for new cost-effective network solutions that are able to provide great bandwidth and improved power efficiency. As such, direct attach cables (DACs) are designed to replace expensive fiber optic cables in some Ethernet applications, like choosing SFP+ DACs and QSFP+ DACs accordingly as 10 Gigabit Ethernet (GbE) and 40GbE cabling solutions to achieve high performance. How much do you know about this kind of cable? Do you know its such basic information as classifications? If not, then you can follow this article to understand DAC in depth based on the two main questions.

Question 1: What Is DAC?

DAC, a kind of optical transceiver assembly, is a form of high speed cable with “transceivers” on either end used to connect switches to routers or servers. Often referred to as twin-ax, this direct attach twin-axial cable is very similar to coaxial cable, except for one additional copper conductor core. DACs are much cheaper than the regular optics, since the “transceivers” on both ends of DACs are not real optics and their components are without optical lasers. In some 10GbE and 40GbE infrastructures, DACs have been selected to replace fiber optic patch cord when the required link length is relatively short. And in storage area network, data center, and high-performance computing connectivity, DACs are preferable choice because of their low cost, low power consumption and high performances.

Question 2: How DAC Is Classified?

When it comes to DAC’s classifications, there exist two primary standards: Ethernet transmission rate, material of cables.

Based on Ethernet transmission rate and construction standard, 10G SFP+ DACs, 40G QSFP+ DACs, and 120G CXP+ DACs are all available, meaning that DAC can be used as transmission medium for 10GbE, 40GbE, and 120GbE applications when combined as transceivers. Typical DAC assemblies have one connector on each end of the cable. Take SFP-10G-AOC1M for example, this Cisco compatible SFP+ to SFP+ Direct-Attach Active Optical Cable assembly has one SFP+ connector on each end of the cable, designed for relatively short reach that is 1m.

SFP-10G-AOC1M, one SFP+ connector at each end

According to material of cables used, DACs are available in direct attach copper cables and active optical cables (AOCs).

Direct Attach Copper Cable

Direct attach copper cables are designed in either active or passive versions, providing flexibility with a choice of 1-, 3-, 5-, 7-, and 10-meter lengths. The former provides signal processing electronics to avoid signal issue, thus to improve signal quality. What’s more, the former can transmit data over a longer distance than the latter which offers a direct electrical connection between corresponding cable ends. Both direct attach passive copper cables and direct attach active copper cables have gained popularity in data centers. For instance, EX-QSFP-40GE-DAC-50CM, the Juniper 40G cabling product, hot-removable and hot-insertable, is the QSFP+ to  QSFP+ direct attach passive copper cable assembly, really suitable for short distances of up to 0.5m(1.6ft), appropriate for highly cost-effective networking connectivity within a rack and between adjacent racks.

EX-QSFP-40GE-DAC-50CM, for short reach

Active Optical Cable

AOC is also one form of DAC. It uses electrical-to-optical conversion on the cable ends to improve speed and distance performance of the cable while mating with electrical interface standard. Compared with direct attach copper cable, its smaller size, electromagnetic interference immunity, lower interconnection loss and longer transmission distance make it popular among consumers.

DACs offer great flexibility in cabling length choices, simplify server connectivity in top-of-rack deployments, and reduce the power needed to transmit data. More importantly, DACs ensure high system reliability after going through rigorous qualification and certification testing, helping network designers to achieve new levels of infrastructure consolidation while expanding application and service capabilities.

Conclusion

DACs are able to provide an end-to-end solution that is easy to maintain, thus helping improve the availability of networks that support mission-critical applications. Fiberstore offers a broad selection of DACs with high quality for state-of art performance, 10G SFP+ DACs, 40G QSFP+ DACs, and 120G CXP+ DACs all included. For more information about DACs, you can visit Fiberstore.

Cabling Data Center Process: Planning & Implementing its Infrastructure

Today’s data centers are the home to diverse bandwidth-demanding devices, like servers, storage systems, and backup devices which are interconnected by networking equipment. All these devices drive the need for reliable and manageable cabling infrastructure with higher performance and more flexibility for today and future growth. While managing the cabling in data centers, two main processes are included: planning the cabling infrastructure and implementing the cables.

Planning the Cabling Infrastructure

As networking equipment becomes denser, and port counts in data centers increase to several hundred ports, managing cables connected to these devices becomes a difficult challenge. Thus, during planning the cabling infrastructure, it’s wise to do the following:

Choosing Fiber Cable Assembly

This assembly has a single connector at one end of the cable and multiple duplex breakout cables at the other end, an alternative to avoid cable management. The LC (Lucent Connector) -MPO (Multifiber Push-On) breakout cable assemblies are designed to do just that. The idea is to pre-connect the high-density, high- port-count LC equipment with LC-MPO breakout cable to dedicated MPO modules within a dedicated patch panel, reducing equipment cabling clutter and improving cable management. This image below show the LC-MPO breakout cable assembly that consolidates six duplex LC ports into one MPO connection.

breakout

Nowadays, this breakout technology is widely used in 40 Gigabit Ethernet (GbE) applications. Like QSFP-4X10G-AOC10M, this product is the QSFP to four SFP+ active optical breakout cable assembly with the 10m short reach.

Using Color to Identify Cables

Color coding simplifies management and can save you hours when you need to trace cables. Cables are available in many colors (table shown below). For instance, multi-mode fiber (MMF) looks in orange (OM1, OM2) and in aqua (OM3), while yellow is usually the color of single-mode fiber (SMF) which is taken as the transmission media when the required distance is as long as 2km, or 10km . Take WSP-Q40GLR4L for example, this 40GBASE-LR4L QSFP+ transceiver works through SMF for 2km link length.

Color coding

Implementing the Cabling Infrastructure

While implementing the cables, the following tasks should be obeyed by.

Testing the Links

Testing cables throughout the installation stage is imperative. Any cables that are relocated or terminated after testing should be retested. Although testing is usually carried out by an authorized cabling implementer, you should obtain a test report for each cable installed as part of the implementation task.

Building a Common Framework for the Racks

This step is to stage a layout that can be mirrored across all racks in data centers for consistency, management, and convenience. Starting with an empty 4-post rack or two, build out and establish an internal standard for placing patch panels, horizontal cable managers, vertical cable managers, and any other devices that are planned for placement into racks or a group of racks. The INTENTION is to fully cable up the common components while monitoring the cooling, power, equipment access, and growth for the main components in the racks.

A good layout discourages cabling in between racks due to lack of available data ports or power supply ports, allowing more power outlets and network ports than you need. This will save you money in the long run as rack density increases, calling for more power and network connectivity. Using correct length cables, route patch cables up or down through horizontal patch panels alleviates overlapping other ports. Some cable slack may be needed to enable easy removal of racked equipment.

Documentation

Typically, the most critical task in cable management is to document the complete infrastructure: including diagrams, cable types, patching information, and cable counts. It’s advised update the documentation and keep it accessible to data center staff on a share drive or intranet Web site.

Stocking Spare Cables

It’s suggestible to maintain an approximately the same amount on the installed cabling and ports in use, so as to face the environment variation or emergency.

Conclusion

Understanding the above-mentioned information about cabling planning and implementation helps you to have a scalable, dependable and manageable cabling infrastructure in data centers. Fiberstore offers many cable management tools, including fiber termination box, cable ties, and distribution cabinet. For more information about cable management solutions, you can visit Fiberstore.

Why Choose 10GBASE-T Interface for 10GbE Infrastructure?

The increasing availability of virtualization applications and unified networking infrastructure puts extreme input/output (I/O) demands on 1 Gigabit Ethernet (GbE), making data centers facing bandwidth challenges. Deploying 10GbE infrastructure can address these problems by delivering greater bandwidth, simplifying network, and lowering power consumption.

Well, the deployment of 10GbE requires cost-effective solution. In general, there are several 10GbE interfaces to choose from, including CX4, SFP+ fiber, SFP+ Direct Attach Copper (DAC), and 10GBASE-T. As for CX4, it’s an older technology that does not meet high density requirements. Although most deployment chooses SFP+ fiber (eg. F5-UPG-SFP+-R) solution, fiber is in no case cost-effective. Besides, SFP+ DAC is limited by its short reach. In such a case, 10GBASE-T is selected as the less power-consuming and cost-saving solution for 10GbE. This article details at what are the reasons that drive the 10GBASE-T to become the suitable 10GbE media option.

Firstly, let’s figure out what is 10GBASE-T. 10GBASE-T, or IEEE 802.3an-2006, is a standard released in 2006 to provide 10Gbit/s connections over unshielded or shielded twisted pair cables, with distances up to 100 meters (330 ft) with RJ45 connectors. 10GBASE-T cable infrastructure can also be used for 1000BASE-T, allowing a gradual upgrade from 1000BASE-T using auto-negotiation to select which speed to use.

10GBASE-T, CAT6 and CAT6A CablingListed below are several reasons why 10GBASE-T become the 10GbE media option.

Flexibility in Reach

Like other copper network implementations using BASE-T standards, 10GBASE-T works for link lengths up to 100 meters, giving network designers a far greater level of flexibility in connecting devices in the data center. Able to realize flexible reach, 10GBASE-T can accommodate either top of the rack, middle of row, or end of the row network topologies, making server placement even more easy and convenient.

Backward Compatibility

10GBASE-T is backward-compatible with existing 1GbE networks, meaning that it can be deployed based on existing 1GbE switch infrastructures in data centers that are cabled with CAT6 and CAT6A (or above) cabling. In other words, when migrating from 1GbE to 10GbE, 10GBASE-T provides an easy path, saving cost.

Reduction in Power Consumption

In widespread deployment of 10GbE networks using 10GBASE-T interface, one challenge lies in the fact that the early physical layer interface chips (PHYs) consumed too much power. The original gigabit chips were roughly 6.5 Watts per port. With technology improvements, the chips improved from one generation to the next, leading to less 1 W per port for 1GbE interfaces. It’s the same with 10GBASET. And owing to the manufacturing processes, the 10GBASE-T reduction in power consumption has been made possible. The figure below shows the relationship between power consumption and wavelength.

power consumption vs. wavelength

When 10GBASE-T adapters were first introduced in 2008, they required 25 W of power for a single port, and later, power has been reduced thanks to the successive generations of developing newer and smaller process technologies. The latest 10GBASE-T adapters require less than 6 W per port,which makes 10GBASE-T suitable for motherboard integration and high-density switches.

Latency

Depending on packet size, latency for 10GBASE-T ranges from just over 2 µs to less than 4 µs—a much tighter latency range. For Ethernet packet sizes of 512 bytes or larger, 10GBASE-T’s overall throughput offers an advantage over 1000BASE-T. Latency for 10GBASE-T is more than three times lower than 1000BASE-T with larger packet sizes. For those enterprise applications that have been operating for years with 1000BASE-T latency, 10GBASE-T latency only makes things better. Many products designed for Local Area Network (LAN) purposely add small amounts of latency to reduce power consumption or CPU overhead.

Broad use of 10GBASE-T interface simplifies data center infrastructures, making it easier to manage server connectivity while delivering the bandwidth needed for heavily virtualized servers and I/O-intensive applications. As the cost continues to fall, and new technological processes further lower power consumption, all these make 10GBASE-T suitable for integration on server motherboards.

Conclusion

10GBASE-T offers the flexible reach, and its backward compatibility with existing 1GbE networks makes it the ideal cost-effective media option for 10GbE infrastructure. As a professional fiber optic product manufacturer and supplier, Fiberstore provides countless 10GBASE-T transceivers for 10GbE applications. Of course, besides 10GBASE-T, other 10GBASE standard transceivers also available in Fiberstore, such as 10GBASE-ER SFP+ (J9153A). For more information about 10GbE interfaces, you can visit Fiberstore.

Consider Two Things Before Deploying 10 Gigabit Ethernet

Over the years, Ethernet technologies have evolved rapidly and amazingly to meet the never-ceasing requirements of higher bandwidth and faster data transmission speeds for high quality network applications, such as live video and video download with high resolution. Through this great evolution, Ethernet technology standards have been designed, like 10 Gigabit Ethernet (GbE).

After IEEE Standard 802.3ae- 2002 for 10GbE was ratified several years ago, some enterprises have begun to deploy 10GbE in their data centers to support bandwidth-needing applications. Before deploying 10GbE, as matter of fact, there are many things that should attract your attention. Here this article lists two important things you need to consider for a reliable 10GbE deployment: 10GbE cabling choices, and 10GbE transceiver types.

10GbE Cabling Choices

Along with the technological revolution, cables used for transmission also experienced progressive development. There are two physical media available for 10GbE transmission: fiber and copper.

10GbE Fiber Cabling Choices

Fiber cables fall on two classifications: single-mode fiber (SMF) and multi-mode fiber (MMF). In SMF, there is only one path for light, while in MMF light flow through multiple paths. SMF is intended for long distance communication and MMF is used for distances of less than 300 m. Commonly used 10GbE ports designed for SMF are 10GBASE-LR, 10GBASE-ER and 10GBASE-ZR, and the ports specified for MMF are 10GBASE-SR and 10GBASE-LRM. It’s of great importance to choose these ports 10GbE transmission when link lengths matter. For example, you can choose a J9150A transceiver when the required distance is less than 300m. In a word, the form factor options depend on your link lengths.

10GbE Copper Cabling Choices

As the structured cabling techniques become mature, copper cabling technology also grasps the chance to develop itself. And more and more people start to choose copper cables as the medium for 10GbE transmission. 10GBASE-T and SFP+ direct attach cables (DAC) standards symbolize copper applications.

10GBASE-T, or IEEE 802.3an-2006, is a standard released in 2006 to provide 10Gbit/s connections over unshielded or shielded twisted pair cables, over distances up to 100 metres (330 ft). It requires the Cat 7 or Cat 6A to reach 100 meters, but can still work on Cat 6, Cat 5E, or even Cat 5 cable when reduced distances are required.

SFP+ DAC is the latest standard for optical transceivers, and it connects directly into an SFP+ housing. In SFP+ DAC cabling assembly, no optical transceiver is used at each end. A cable was invented with each end physically resembling a SFP+ transceiver, but with none of the expensive electronic components. This creation is known as DAC. Actually, besides 10GbE applications, DAC is also considered as a cost-effective solution to replace fiber patch cables sometimes in 40GbE systems. Like QSFP-H40G-ACU10M, this Cisco 40G cabling product is the QSFP to QSFP direct attach passive copper cable assembly designed for 40G links.

QSFP-H40G-ACU10M ,QSFP to QSFP direct attach passive copper cable assembly

10GbE Transceiver Types

After choosing cables, you need to select devices that connect these cables to your networks. These devices are transceivers. 10GbE has four transceiver types: XENPAK (and related X2 and XPAK), GBIC, SFP and SFP+.

XENPAK is a Multisource Agreement (MSA) that defines a fiber-optic or wired transceiver module which conforms to the 10 Gigabit Ethernet (10GbE) standard of the Institute of Electrical and Electronics Engineers (IEEE) 802.3 working group.

X2 defines a smaller form-factor 10 Gb/s pluggable fiber optic transceiver optimized for 802.3ae Ethernet,ANSI/ITUT OC192/STM- 64 SONET/SDH interfaces,ITUT G.709,OIF OC192 VSR,INCITS/ANSI 10GFC (10 Gigabit Fibre Channel) and other 10 Gigabit applications.X2 is initially centered on optical links to 10 kilometers and is ideally suited for Ethernet,Fibre Channel and telecom switches and standard PCI (peripheral component interconnect) based server and storage connections. X2 is physically smaller than XENPAK but maintains the mature electrical I/O specification based on the XENPAK MSA and continues to provide robust thermal performance and electromagnetic shielding. The 10GB X2 fiber optic transceivers series include X2-10GB-SR, X2-10GB-LR, X2-10GB-ER and X2-10GB-ZR, they are designed based on the X2 MSA and IEEE802.3ae. They’re created for the integrated systems solution provide, fiber optics distributor along with other IT distributors.

SFP+, also called SFP Plus, is short for enhanced small form-factor pluggable, an enhanced version of the SFP that supports data rates up to 16Gbit/s. SFP+ 10GbE transceiver series include SFP+ 10GBASE-SR, SFP+ 10GBASE-LR, SFP+ 10GBASE-ER, and so on. Among these types, 10GBASE-SR is widely used when the required distance is less than 500m. Say SFP-10G-SR, this Cisco 10GBASE-SR SFP+ transceiver listed in Fiberstore is designed to support 10GbE applications with the maximum distance reach of 300m.

Conclusioni

After discussion, maybe you have obtained a better understanding of 10GbE cables and transceivers, which helps you to better choose the right devices for your 10GbE applications. Fiberstore supplies various numbers of 10GbE cables and transceivers which are quality assured. For more information about 10GbE solutions, you can visit Fiberstore directly.