Set Top Box: The Center of Your Viewing World
The Set Top Box (STB) is the center of your viewing world delivering premium content and services to you through a variety of broadcasting mediums (Satellite, Cable, Terrestrial, IP). Consumers are demanding media-rich home entertainment requiring STB evolution to include more advanced features and services and driving an architecture for faster performance, scalability and security.
More than just ABC/CBS/NBC with a Remote
In a Digital TV (DTV) system, a Set Top Box receives, filters and processes all the content and services accessed by the TV viewer. Evolving from a simple Standard Definition device that offered a basic Electronic Program Guide (EPG) information and access to a limited set of services and content, newer STBs support:
- High definition channels
- Multi-tuner capabilities (enabling simultaneous viewing and recording)
- IPTV in addition to broadcast TV
- Pay per view/video on demand services
- Internet interactivity
STBs are also increasingly assuming the functions of home gateway or home server devices that can store as well as distribute content to many TVs, PCs and portable devices throughout different rooms inside the home.
Give me Access to that Content
Increasingly, consumers want access to the content on their terms: on-demand and on this device. While everyone would love to get the content for free, normally access comes at a cost. Consequently, both the consumer and the pay-TV operator must rely on the STB to be the platform for secure transactions and content protection.
For consumers wanting privacy and content providers wanting to protect their revenue stream, security within the STB is critical and falls in two areas:
- Conditional access systems (CAS) – Securing the content as it is delivered from the operator to the STB by ensuring that consumers can only play content to which they are entitled. The overall user entitlement process is handled by the conditional access kernel (CAK) and a conditional access module – often contained in a SmartCard- inside the STB.
- DRM (digital rights management) – Protecting the content as it is stored in the STB or shared with other devices and users through a home network such as WiFi. The DRM technology is typically handled by the middleware software and therefore needs to be secured from hacking as well.
NOR flash provides a key role
NOR Flash contains the boot code, CA kernel, operating system kernel, device drivers, middleware and the EPG. The boot code and the operating system code require high random read performance and data retention making NOR flash the ideal non-volatile memory solution, directly impact the viewing experience by providing a near “Instant On” experience so they can access their desired programs quickly. Unlike other consumer electronic systems, TV operators actively manage the STB once it has been supplied to the consumer. Higher-density NOR flash memory can be provisioned for future software additions or upgrades.
In providing security in the STB, NOR Flash is particularly important. To secure the CA kernel, the OS and the middleware codes, the NOR flash contains security features such as permanent lockable region to protect against write or erase access by hackers and pirates and a One Time Programmable (OTP) region for sensitive data such as encryption keys and unique IDs.
Spansion’s 65nm NOR products Family offer features that address the STB’s performance, scalability, performance and total cost of ownership. The Spansion® GL-S family is the latest generation of Parallel NOR products that have been well established in the STB market for many years, and Spansion Serial NOR products have ramped up quickly in STB applications since 2010 because of its reduced pin count which simplifies board layout and results in lower system costs and reduces the form factor of many embedded designs. The latest generation of Serial flash, Spansion FL-S family, brings high performance benefits to simplified memory interface.