Is this thing on? (tap, tap)

It started as a hobbyist technology and recently found a foothold at forward-thinking federal agencies. The White House uses it to distribute the president's weekly radio address. The State Department's Voice of America exploits it for broadcasts. And hold onto your hats, because House Republicans and Democrats agree on something. In this case it's that podcasting'a popular new method of publishing audio programs online'provides an efficient avenue for expressing their views via the Internet.Last month, NASA delivered the first-ever podcast from space. On the day before the space shuttle Columbia returned to earth, crewmember Steve Robinson transmitted an audio file explaining how he'd repaired the craft's damaged tiles and reflecting on his opportunity to 'watch the sun come up over the bottom of the space shuttle.'Not bad for a technology that's been in widespread use for less than a year, a technology made popular by Internet hackers who wanted to send out homemade radio shows. But just as other Web-based tools have changed the way agencies operate (think online search, e-business, WebEx, XML) podcasting may prove handy for unique government missions. And getting started in podcasting can be easy.The term podcasting is a hybrid of broadcasting and iPod, the latter being the popular brand of portable digital music player sold by Apple Computer Inc. In itself, the name is something of a misnomer because any digital music player or playback software could be used for listening to podcasts, which are commonly created in generic MP3 format, not just Apple's.To end users, podcasting can be thought of as a subscription to an audio program in which a list of available audio files is automatically downloaded to a personal computer'or the files themselves may be downloaded. From there, users can listen to the files on their PCs or shift them to their portable MP3 players for on-the-go enjoyment.For federal organizations already producing audio content, podcasts provide another conduit to their intended audience. Unlike radio programs, podcasts can be heard at the listener's convenience. In fact, experts say podcasts can tap into a user base of millions.Podcast services rely on Really Simple Syndication, or RSS, an Extensible Markup Language-based format for setting up automatic feeds that can be read by browsers and other applications.Users can be notified through RSS when a new podcast is available.If an agency has already set up an RSS feed for text-based information such as press releases, setting up a podcast involves minimal additional work.Not surprisingly, the early adopters of podcasting have been those agencies that already create audio programs. NASA, the Air Force and the State Department's Voice of America have either jumped on the podcasting bandwagon or are in the process.NASA's Science@NASA public information program, run by the science directorate of the Marshall Space Flight Center, started podcasting in December 2004, using some of the same radio features it had been producing for several years, said Ron Koczor, who manages the program.'Once you have the story production and the audio production, then it is almost trivial to get the RSS out,' Koczor said.The Science@NASA Web site was started in 1996 to share some of the agency's success stories of scientific research, offering them in print form and as audio downloads in MP3 format.The program has built an e-mail subscriber list of 200,000 for the English edition and 45,000 for the Spanish edition, according to Bryan Walls, curator of the Science@NASA Web site.Recipients include educational institutions as well as members of the press and the public.For Walls, offering podcasts is now another way for NASA to get the word out about what it's doing.'It's like Tivo for radio,' he said, referring to the popular consumer appliance that automatically records television shows on a hard drive and keeps them for later viewing. 'Once [users] set up in a podcast client, the stories are automatically downloaded for them.'Instead of depending on the user to go to the Web site to check for new audio programs, NASA periodically pushes a list of available material to users' podcast or RSS clients.Users then can peruse the new entries at their discretion, or allow the software to download audio files automatically.Another long-time producer of radio shows, the Air Force Broadcasting Service, started offering its own podcasts last month.The Air Force news agency receives audio spots from detachments around the world, as well as from individual bases. The service packages the material for the Armed Services Radio and makes it available on the Air Force Web site.It was a short step to creating a podcast once that process was in place, said Kim McDonald, spokesperson for Air Force News Agency.The service started offering one four-minute podcast a day with plans to increase the amount of available material as manpower permits.Perhaps the granddaddy of federal radio broadcasting is the Voice of America, an international broadcasting service run by the State Department's International Broadcasting Bureau.VOA presents U.S. culture and policy to millions of listeners around the globe. In addition to its programs over the airwaves, VOA has long offered its radio programs in the MP3 format. It has also used RSS feeds for some time. Now the organization is starting an effort to fuse the two as podcasts, said Ken Berman, head of IT for IBB.In addition to government agencies, other parties are using podcasting to relay government-generated information. C-Span is podcasting such government source materials as hearings.And a Phoenix attorney has created a podcast consisting entirely of synthesized speech recordings of recent U.S. patent law case summaries.While agencies such as NASA aim for as broad an audience as possible, Andrew Lahser's PatentPod actually shows how well podcasts can work for small, specialized audiences. Lahser, who works for the Phoenix, Ariz.-based Stoneman Law Offices Ltd., admits that only a small number of people in the world are interested in hearing patent law case summaries. But the cost to set up the system was also minimal.Lahser actually began making digital recordings for his own use because he wanted to listen to the cases during his long drive to work. He used basic text-to-speech software and wrote some special code to filter out those parts of the ruling that wouldn't make for good drive-time listening.Setting up an RSS feed was equally easy, he said. He uses the free blogging site Blogger.com for his service's home page. Another free service, called Feedburner, publishes the podcast so it is accessible via a number of newsreaders.A low-cost Web site hosting company, Go Daddy Software Inc. of Scottsdale, Ariz., provides the storage.Should the popularity of his podcasts spike, Lahser figures he could offload some of the traffic to peer-to-peer networks such as BitTorrent.'These free online tools like each other'they work well together,' he said.Seasoned users of Internet streaming audio may wonder what's so new about podcasting. The answer is, not a lot, at least in terms of the tools used. 'The technology is old, but the way it is being used is cutting edge,' Lahser said.Setting up a podcast takes two main steps. One step is recording the material; the other is setting up a feed.Recording can be as simple as recording a conversation or monologue over a microphone plug into to a computer's sound card.Or text can be read by the computer itself, using any text-to-speech application. Agencies such as VOA that produce broadcasts professionally can convert files from the formats they were recorded in, such as .WAV, into the podcast format using a program.Podcast audio files themselves are usually MP3 files, the compression codec long used for digitally encoding music for playback on computers and digital players. The MP3 format offers the advantage of being compact enough for online delivery. Lahser's 48-minute summary of Warner Lambert v. Teva Pharmaceuticals, for instance, is only about 8.5 MB.This compactness was one factor that made MP3 attractive to VOA, Berman said. Since VOA serves countries with limited Internet connections, the agency wanted to make accessing the podcasts as easy as possible. People can download MP3 files at their own speed, rather than requiring a minimum amount of bandwidth to get real-time audio streams.Another advantage of the MP3 format is the rampant proliferation of MP3 software, both for creating and listening to files. Most streaming formats, such as those offered by RealNetworks Inc. of Seattle, Wash., require a player available only from that vendor, Wyatt said.Going with something as widely used as MP3 ensures more tools will work with it.Once a podcast audio file is composed, it is then posted on a Web or File Transfer Protocol site, and its debut is heralded on an RSS feed.The feed is usually a plain text listing all the files available for download. The users' newsfeed software periodically downloads this file to check for updates. Each file can contain detailed descriptions of the podcast, including title, date, topic, etc.If you already have RSS feeds running from your agency servers, it's simply a matter of setting up a new RSS file for your podcast.One of the podcast's chief strengths is that you don't have to worry about user interfaces, Lahser said. There are a large number of programs and Web sites that use RSS feeds, and they all present the material in customized ways. Apple's iTunes digital music service, for instance, offers a podcast directory. To get listed on iTunes, you simply submit the Web address for your RSS feed. Internet portal Yahoo also provides a directory of podcasts with a different look and feel from iTunes. In addition, there are countless PC-based 'podcatching' applications and Web sites that check feeds on a regular basis.By submitting the feed address to such sites, agencies could potentially tap into millions of users.Although the initial uses of podcasting may seem confined to outreach by particularly well-funded agencies, early ad-opters are bullish on the technology in other places within government.'Anyplace you post a written version of information, you could a post an audio version as well,' Koczor said. 'Some people learn best by reading, and other people learn best by listening.'