When I first heard about the priorities of the US stimulus package (the official name is American Recovery and Reinvestment Act, or ARRA), I was very hopeful that it will drastically improve the broadband infrastructure and pave the way for wider adoption of video communication across the United States. Video - and to a lesser extent wideband audio - require quite a lot of bandwidth combined with some quality of service requirements , for example, packet loss should not be more than 5%, jitter should not be more than 40ms, and latency … well, latency is negotiable but a real nice real-time interaction calls for maximum 250ms end-to-end.
I live in a large city which is part of a large metropolitan area of 5-6 million people, and I do have choices among cable, xDSL, FTTH, etc. to get high-speed access to the IP network. In addition, Polycom’s office is not far away and once I connect to the corporate network, I can use much faster and more predictable links to connect to other Polycom offices around the world. But what if I lived in a remote rural area? What if I only could get modem or satellite connection, or connect through the packet service of a mobile network? I would not be able to use video communication – at least not at quality level that makes it useful - and even wideband audio would be a challenge.
A huge part of the US population cannot use video communication because the broadband access network just does not support this application, and the stimulus money spent on broadband initiatives should improve the situation. Wouldn’t it be great to allow patients at remote locations to access best specialist over video and rural schools to connect to world-class education institutions such as the Manhattan School of Music and teach music over advanced audio-video technology?
But how does the stimulus package apply to broadband access? The National Telecommunications and Information Administration (NTIA) established the Broadband Technology Opportunities Program (BTOP) which makes available grants for deploying broadband infrastructure in ‘unserved’ and ‘underserved’ areas in the United States, enhancing broadband capacity at public computer centers, and promoting sustainable broadband adoption projects. The Rural Utilities Service (RUS) has a program called BIP (Broadband Initiatives Program); it extends loans, grants, and loan/grant combinations to facilitate broadband deployment in rural areas. When NTIA or RUS announce a Notice of Funds Availability (NOFA), there is a lot of excitement in the market.
I am actually less interested in the logistics of fund distribution but am rather concerned about the ‘broadband service’ definition used in all NOFA documents. It originates from the Federal Communication Commission (FCC) and stipulates that ‘broadband service’ is everything above 768 kilobits per second downstream (i.e. from service provider to user) and 200 kilobits per second upstream (i.e. from user to service provider). Real-time video requires symmetric bandwidth, although video systems would adjust the audio and video quality level depending on the available bandwidth in each direction. At the minimum ‘broadband service’ level defined above, the user could see acceptable video quality coming from the far-end but would be able to only send low-quality video to the far-end.
I understand that when the broadband service definition was discussed at FCC, the wire-line companies wanted higher limits, in line with what cable and xDSL technology can support, while wireless companies wanted far lower limits, like the ones adopted, so that they can play in broadband access as well. FCC decided to set the bar low enough for everyone to be able to play but allow competition in offering higher speeds. There is fair amount of skepticism that this model will get us to higher speeds than the defined minimums. Several organizations including Internet2 proposed two-tier approach with a lower broadband service limit set for households and a higher limit set for institutions/organizations; however, FCC’ final definition did not recognize that broadband for institutions is different from broadband for end users.
At Polycom, we take network bandwidth limitations very seriously, and have been working on new compression techniques that reduce bandwidth usage for video communication. This resulted in the implementation of the H.264 High Profile which I described in detail in my previous post. And while we can now compress Standard Definition video to about 128 kilobits per second, the additional bit rate necessary for good quality audio and the IP protocol overhead still does not allow us to fit into the very thin 200-kilobits-per-second pipe. Don’t forget that bandwidth is not the only requirement for real-time video; latency, jitter and packet loss are very important and none of these parameters is explicitly required or defined in any NTIA or RUS documents.
No comments:
Post a Comment