Multimedia home networking enables you to share audio, video, and data across multiple media-centric devices (such as TVs, portable media players, cameras, and cell phones) and data-centric devices (such as PCs and PDAs) using a secure home network. In the last decade, broadband connectivity for Internet access has become common and PCs have been used for not just data access but also to access and share multimedia files. At the same time, digital devices such as cameras and portable media players have become popular and multimedia content created with such devices has proliferated. However, such content is difficult to share among devices because there are no connectivity standards between the different devices within a home. By enabling a high-bandwidth, quality of service (QoS)-driven, multimedia home network with a standard interface, you can access home movies, multimedia files, and the Internet from almost anywhere in the house.
Within a home network, a media server acts as a central unit. It typically has a large hard disk (hundreds of gigabytes) for storage of audio, video, and data files and high-speed connectivity to be able to stream and store files to and from different devices. Triple speed Ethernet, PCI express, USB, FireWire, UWB, and Wi-Fi are among some of the interfaces the home network has to support. It also may need transcoding capabilities to convert between video formats. Figure 1 shows an example of a media server block diagram.
Figure 1. Home Multimedia Server Block Diagram
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Reducing the Design Risk With FPGAs
The home networking device market is still in an evolution phase with many uncertainties, including which networking technologies and video formats to support. Existing ASSP solutions do not support all the various evolving networking technologies or the video formats, and developing a custom ASIC is very time consuming. Employing only ASIC or ASSP design methodologies puts manufacturers at significant risk of either being late to the market or releasing a product with dated features. Leveraging programmable logic in home networked products provides agility for time-to-market and the flexibility of adding the latest features to products. With an FPGA on board, you can add unsupported networking standards or video formats. You can also use FPGAs for transcoding capabilities.
Digital Living Network Alliance (DLNA) and Hi-Def A-V Network Alliance (HANA) are key industry groups whose goal is to align manufacturers and ensure compatibility between home networking products. Different companies are pursuing different technologies, broadly classified as wired or wireless, to enable multimedia home networks. Table 1 describes popular home networking technologies.
|Table 1. Popular Home Networking Technologies|
|802.11n||An extension 802.11 Wi-Fi wireless standard. Operates in a 2.4-GHz or 5-GHz frequency spectrum and can support greater than 100-Mbps bandwidth. It’s also called multiple-input multiple-output (MIMO) technology as it uses multiple antennas for receive and transmit to enable higher data rates.|
|Multimedia Over Coaxial Alliance (MOCA)||Uses existing coaxial cable in homes to distribute audio, video, and data with target speeds greater than 100 Mbps.|
|HomePNA||Home Phoneline Networking Alliance uses phone lines to run Ethernet with data rates in excess of 300 Mbps.|
|HomePlug Audio/Video (A/V)||HomePlug A/V provides networking over in-home power lines. Effective bandwidth is in excess of 100 Mbps. Uses windowed orthogonal frequency division multiplexing (OFDM) for modulation.|
|Wireless High Definition (HD)||Group working towards providing transmission of uncompressed HD video at data rates up to 5 Gbps in the 60-GHz radio frequency.|