Three Different Types of Transceivers

There are numerous types of transceivers available that can be used in a variety of applications including radio applications and telecommunications applications. Different specifications and designs are employed to meet the changing needs of designers. This article will introduce three primary types of transceivers used in today’s telecommunication systems.

SFP Transceiver

The small form-factor pluggable (SFP) is a compact and hot-pluggable transceiver used for both telecommunication and data communications applications. The form factor and electrical interface are specified by a multi-source agreement (MSA). It interfaces a network device motherboard (for a switch, router, media converter or similar device) to a fiber optic or copper networking cable. SFP was one of the most popular versions of transceivers until the enhanced version was introduced. Select the SFP devices for the best results.

Fiberstore’s SFP transceivers are available for designers to use in a variety of applications. These transceivers come in a variety of transmitter and receiver types. Users can select an appropriate transceiver by reviewing several different categories. Some common categories include: copper and fiber, single-mode and multi-mode, SX (transmits up to 550m at 1.25 Gb/s), LX (transmits up to 10 km), and BX (transmits up to 10 km). For example, HP J8177C compatible 1000BASE-T SFP copper transceiver is high performance and cost-effective transceiver for 100m distance over Cat 5 UTP cable.

SFP+ Transceiver

The enhanced small form-factor pluggable (SFP+) is an enhanced version of SFP and is designed to support data rates up to 10 Gbit/s. SFP+ was designed to have higher port density compared to SFP. The SFP+ specification was first published on May 9, 2006, and version 4.1 published on July 6, 2009. SFP+ supports 8Gbit/s Fiber Channel, 10 Gigabit Ethernet and Optical Transport Network standard OTU2. The SFP+ product family includes cages, connectors, and copper cable assemblies. The SFP+ transceiver modules are specified for 8Gbps/10Gbps/16Gbps Fiber Channel and 10-Gigabit Ethernet applications. In addition, they have the ability to connect to a variety of different types of optical fiber and are highly flexible. That’s why they are so desirable to designers.

XFP Transceiver

XFP transceiver is a hot-pluggable and protocol-independent 10 Gbit/s optical transceiver designed to help drive cost and power consumption out of 10 Gbit/s optical networking applications. This particular XFP specification was developed by the XFP Multi-Source Agreement Group. XFP transceivers are capable of operating at wavelengths of 850 nm, 1310 nm, and 1550 nm. They are capable of operating at a single wavelength or through the use of dense wavelength-division multiplexing techniques.

There are a variety of transceiver types available, but the most popular ones include: SR (850 nm and can transmit up to 300 m), LR, ER, and ZR. LR is 1310 nm and can transmit distances up to 10 km. For example, Juniper XFP-10G-L-OC192-SR1 compatible 10GBASE-LR XFP transceiver from Fiberstore operates at a wavelength of 1310 nm at up to 10km links. ER is characterized by 1550 nm and can transmit distances of 40 km. ZR can transmit distances up to 80 km. Designers prefer to use XFP packaging because it has a smaller footprint than other devices.

Choose the Best Transceiver for Your Design

There are also other types of transceivers apart from the above-mentioned. Since there are so many types of transceivers, try to find the best transceiver for your design and applications. When the design is optimized, everything seems to fall into place for the end user. The reliability of your design will improve, and your end-user will reap the benefits of a system that will stand the test of time and the rigors of a stressful environment.

How to Choose the 10G Transceivers

From the origin of 10G Ethernet, 10G optical transceivers have been developed along the way to meet the increasing demand for higher-performance servers, storage and interconnects. However, selecting the best type of 10G optical transceivers is not always easy. There are a variety of factors that must be considered. To be able to select a matching transceiver for a given application and hardware, all below stated parameters must be considered.

Transceiver “form-factor” / MSA Type

The transceiver has to 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. XENPAK is the first MSA for 10 Gigabit Ethernet. The XENPAK MSA defines a fiber optic or wired transceiver module which conforms to the 10 Gigabit Ethernet standard of the IEEE 802.3 working group. Then X2 followed with smaller size. XFP specification was launched after X2 with more contact size. SFP and SFP+ are the newest and the most common form factors which enable 10G Ethernet.

Transport Media

Choose the right 10G optical transceivers according to the transport media, namely the fiber type. There are a number of 10 Gb/s media systems, with a few of the most widely used systems specified in the standard described here:

• 10GBASE-CX4
  10 Gb/s Ethernet over short-range copper cable assemblies (15 m maximum).
• 10GBASE-T
  10 Gb/s Ethernet over unshielded and shielded twisted-pair cables. Category 6A or better twisted-pair cables are required to reach the maximum distance specified.
• 10GBASE-SR
  10 Gb/s Ethernet over short-range multimode fiber optic cables.
• 10GBASE-LR
  10 Gb/s Ethernet over long-range single-mode fiber optic cables.

Connector Type

Choose the right transceivers which are compliant with the proper connectors. The connectors widely-used mainly have following types: Duplex LC connector, MPO connector, and MTP connector (a high performance MPO connector). For instance, HP 455883-B21 10GBASE-SR SFP+ transceiver module provided by Fiberstore is compliant with the Duplex LC connector.  

Transmission Distance

When we choose the ideal 10G optical transceivers, we must consider the transmission distance and the reach requirements we need in reality. The most common types of transceivers divided by its transmission distance can reach up to 100m, 150m, 300m, 400m, 1km, 2km, 10km, 40km, etc. For example, Cisco SFP-10G-SR compatible 10GBASE-SR SFP+ transceiver supports link lengths of 300m over multimode fiber cables. And Juniper XFP-10G-L-OC192-SR1 compatible 10GBASE-LR transceiver provides superior performance for SONET /SDH and Ethernet applications at up to 10km links.  

Wavelength

The wavelength the transceivers operate with is an important factor in choosing the proper 10G optical transceivers. For instance, Fiberstore's 10G CWDM XFP is designed for single mode fiber and operates at a nominal wavelength of CWDM wavelength. There are fourteen center wavelengths available from 1350nm to 1610nm, with each step 20nm.

Fiberstore provides various types of 10G optical transceivers including single-mode and multi-mode with different channels and wavelengths. In order to achieve a fast and successful selection of the 10G optical transceivers, we should consider all the above-mentioned factors comprehensively.

XFP Transceiver Overview

Since the module multi-source agreement (MSA) association announced the XFP specification, MSA form factors for 10 Gbit/s optical transceivers have evolved along two separate paths that are now converging on XFP as a universal long-term solution. XFP transceiver is an ultra-small, hot-pluggable, 10 Gbit/s optical transceiver designed to help drive cost and power consumption out of 10 Gbit/s optical networking applications, and enables rapid advances in port density after the previous X2 and XPAK transceiver as well.

Features of XFP Transceiver

• Supports 10GBASE Ethernet and OC-192/STM-64 data rates
• Hot-swappable input/output device plugs into a XFP port
• Provides flexibility of interface choice
• Available for various transmission distance ranging from 300 m to 80 km
• Operates over a single wavelength or use dense wavelength-division multiplexing techniques
• Compliance with XFP Multi-Source Agreement (MSA)
• Digital diagnostic monitoring
• Uses LC fiber connector type to achieve high density
• A 1310nm directly modulated laser with PIN for 10 km
• A 1550nm cooled EML with PIN for 40 or 80 km
Besides, XFP transceiver costs approximately 30% to 40% less than earlier MSA form factors, and is far more compact, giving two to three times the density. As it is multiprotocol and hot-pluggable, it's not surprising that the industries are lining up behind it. Its versatility, low cost, and small footprint are making XFP transceiver the choice for an ever-growing set of 10 Gbit/s communications applications.

Applications of XFP Transceiver

XFP transceiver supports 10 Gigabit Ethernet, 10 Gbit/s Fibre Channel, synchronous optical networking (SONET) at OC-192 rates, synchronous optical networking STM-64, 10 Gbit/s Optical Transport Network(OTN) OTU-2, and parallel optics links. The XFP transceiver can be applied in longer reach applications for the metro-WDM market, which requires a cost-optimized, managed platform supporting different services and suitable for applications in diversified network topologies. For example, XFP-10G-L-OC192-SR1 transceiver provided by Fiberstore can support diverse applications for SDH/Sonet equipment including FEC (9.95Gb/s to 10.7Gb/s), as well as Ethernet LAN(10.325Gb/s) and WAN(9.95Gb/s) applications. The high performance uncooled 1310nm DFB transmitter and high sensitivity PIN receiver provide superior performance for SONET /SDH and Ethernet applications at up to 10km links. Digital diagnostics functions are available via a 2-wire serial interface, as specified in the XFP MSA.

Developing Trend of XFP Transceiver

The developing trend of transceiver depends on customers' needs. And the fact is that customers always need faster, smaller, and more cost-effective transceivers with lower power consumption. Different package of transceivers have come to the market as technology develops. With the fact that the new generation of transceiver package form will gradually replace the older generation, the old version also need to upgrade otherwise it has to be replaced gradually till disappear. For example, when XFP came to us, the transponder was replaced gradually. By adding tunable technique, the 10G transponders have still been in the market so far. But now SFP+ transceiver module also achieves tunable technique which indicates that the need for XFP is gradually decreasing.

Fiberstore manufactures and supplies a complete range of XFP transceiver modules which can be customized. In addition, Fiberstore also provides compatible XFP transceivers as alternatives to those branded by Cisco, HP, Juniper Networks. The aim is to offer customers high-performance and cost-effective products to fulfill their requirements, contributing this way to the customer's success and satisfaction.