A transceiver is a device comprising both a transmitter and a receiver that are combined and share common circuitry or a single housing. When no circuitry is common between transmit and receive functions, the device is a transmitter-receiver. The term originated in the early 1920s. Similar devices include transponders, transverters, and repeaters.

Data centers are processing tons of data and need to retrieve the data at record speeds. This situation requires that every aspect of the design be optimized, including optical transceiver technology. Since most data centers are connecting at 100 Mbps or higher, all optical transceiver technology, including 10 Gbps, must meet the increasing demand for bandwidth. The technology needs to meet the bandwidth requirements not only for storage and switch applications but also for server applications. Here is what you need to know about optical transceivers and server technology.

Optical Transceivers: Smaller, More Affordable and Less Power Hungry

Designers then needed optical transceivers that could consume less power and cost less while being smaller in size. Optical transceivers that met these requirements are typically recognized in the technology world through the XFP multisource agreement (MSA).

Packages for optical transceivers are shrinking. They evolved from a 4" x 3.5" footprint to a 2.3" x 0.68" package. This is a significant change that has allowed the overall footprint of servers to decrease, making data centers smaller and more streamlined.

In addition, optical-transceiver power consumption has dropped 10 W to 3 W or lower—a significant stride that has enabled designers to get more out of transceiver technology. Lower power consumption means lower prices in the design and in power costs. These savings are incredible for people in the technology field.

Silicon advancements have made all of these benefits possible. Manufacturers introduce optical components that will enable development of new transceivers. Advancements can help clients achieve 10 Gbps and move from 10 Mbps to 100 Mbps at decreasing prices. That's why it is so important for designers to remain progressive and to continue to seek new solutions to old problems.

Port density is one of the single most important factors in transceiver design. Most data centers consist of multiple racks of switching equipment that can achieve high speeds. To control costs, designers have refined their designs and tried to improve their manufacturing process technologies to assist with this effort. Increasing port density is just one way to decrease system costs.

XFP optical transceivers support up to 16 channels, which can plug into a standard server equipment rack. Although high port density is necessary to reducing costs, addressing heat dissipation has become a critical issue as well. Power requirements can be met using VCSEL technology and also using the latest silicon. XFP 10 Gbps optical transceivers have greatly accelerated and converged in terms of development efforts.

XFP optical transceivers have been designed to conform to the requirements of servers and to the performance and distance requirements of 10 Gbps Ethernet. The desired server transmission rates and encoding qualifications can easily be met by an XFP optical transceiver. As server technology evolves, optical transceivers follow its lead accordingly. When designers moved digital functions out of transceivers and into ASICs (application-specific integrated circuits), the efficiency of the transceivers improved.

Inefficiencies of XFP Transceivers
Overcoming the loss associated with optical transceivers is one of the primary concerns with XFP optical transceivers. Crosstalk is another concern. As technology improves and inefficiencies are minimized, servers will become more efficient. This effort requires some assistance from designers and manufacturers to aid in the evolution of servers and transceiver technology.

Keep in mind that optical transceivers in a server convert electrical signals into optical signals. This is what allows them to achieve speeds in excess of 25 Gbps. If they are bulky, however, they are more prone to transmission losses and signal degradation—another impediment to faster transmission.

To address these issues, circuit technology has emerged in conjunction with XFP transceivers to suppress reflections and increase data rates. Efforts have also been made to decrease costs and footprint by incorporating flexible printed-circuit boards and optical devices. Some companies have developed film-type lens sheets to address these issues, but they have not eliminated them entirely. Future technology may erase this impediment from existence.