The evolution of the pluggable module

The pluggable in the video broadcast/media market

As discussed earlier, the transceiver SFP was not popular in the broadcast and media industry for a number of commercial and technical reasons. Video transmission over fiber was expensive and only used for niche applications. But with HDTV, serial digital video speeds of 1.5Gb/s launched fiber into the mainstream of broadcast and media industries. Manufacturers first built their own electrical-to-optical (E2O) and optical-to-electrical (O2E) converters with discrete components. Hurdles such as pathological signal performance often impeded development. Careful design techniques were required to manage the high DC content of the SDI signal. Products that did offer error-free operation required entire circuit boards on components. They were bulky and expensive.

These early converters were inflexible and lacked real-time diagnostics. At this same time period, around the year 2000, rich, internal diagnostic features were not typically integrated with core equipment such as routers, multiviewers, cameras or production switchers.

Even though HDTV launched in 1998, it was not until 2004 that the first optical SFP (V_SFP) and SFF (V_SFF) for the video industry were developed that were capable of meeting the demanding requirements of the SMPTE SDI signals. In 2007, the broadcast industry looked to enable 1080p video signals pushing the data rate to 3Gb/s for SDI data transmission. And more companies started to provide SFPs that were capable of managing 3Gb/s data and the video pathological signals. In addition to transceivers, dual transmitters and dual receivers were developed to more closely meet the needs of the broadcast and media industries.

Today, many suppliers offer basic optical SFPs. When manufacturers select optical SFPs, various factors must be taken into account: optical launch power, receiver sensitivity, mechanical robustness, internal diagnostics, and, of course, price and lead time.

Basic digital diagnostics are defined in the SFP MSA specification. The diagnostic information is accessible via a serial, industry standard, I2C bus. The host system can then control basic SFP parameters such as transmitter enable and get information from the SFP such as internal temperature, voltage or receive signal strength.

The SFP brought various benefits to both manufacturers and users:

• Interoperability between equipment for fiber transmission;
• Simplified stocking and management of inventory;
• Small footprint for both products and inventory storage;
• Faster mean time to repair (MTTR);
• Faster time to market for product design.

The embedded SFP (emSFP)

The SFP is great for basic O2E and E2O for fiber, but copper cable is still widely deployed and must be supported, and standard SFPs do not help with system integration. If a facility or installation needs to handle multiple physical layers and different signal standards, you may need multiple converters. The emSFP was created to fill this need and to build one unique platform to support exactly what the user needs.

The emSFP product line covers the standard coaxial cable, fiber optic, CVBS (NTSC/PAL) to SDI conversion, HDMI-to-SDI conversion and ASI-to-IP encapsulation. These features enable a high level of integration in the core platform and a new level of flexibility for manufacturers and users.

In every case, these modules convert a serial SDI signal to the required physical layer format and transmission standard and protocol. These modules permit users to build a product today and future-proof the platform by upgrading the emSFP, not the core.

Internal I2C communication with the SFP allows easy integration with SNMP monitoring and control
software applications.

RAS for the broadcast and media industry

We have explored the history and timeline of pluggable modules, covering key components that shaped the telecom, broadcast and media industries. (See Figure 10.)

SFP and SFP+ modules have proven to be the most accepted and widely used pluggable technology in telecom, and now broadcast. The constant demand for higher speed, more processing and flexibility, and lower power continues to shape the role of the SFP, emSFP and SFP+ in broadcast and media. The technical teething pains and RAS fundamentals that successfully shaped and contributed to the growth and success of networking worldwide are now available to the local broadcaster.

---

—Renaud Lavoie is president and CEO of Embrionix.