Asterisk is the world’s leading open source telephony engine and tool kit. Offering flexibility unheard of in the world of proprietary communications, Asterisk empowers developers and integrators to create advanced communication solutions...for free.
Asterisk can be configured as the core of an IP or hybrid PBX, switching calls, managing routes, enabling features, and connecting callers with the outside world over IP, analog (POTS), and digital (T1/E1) connections.
Asterisk runs on a wide variety of operating systems including Linux, Mac OS X, OpenBSD, FreeBSD and Sun Solaris and provides all of the features you would expect from a PBX including many advanced features that are often associated with high end (and high cost) proprietary PBXs.
Asterisk's architecture is designed for maximum flexibility and supports Voice over IP in many protocols, and can interoperate with almost all standards-based telephony equipment using relatively inexpensive hardware.
The main company selling and supporting Asterisk-based products is Digium, which obviously knows the open source world pretty well. Nonetheless, it found itself confronted with a licensing problem recently:
Open Source Asterisk has had for quite some time the ability to play Music On Hold (MOH) to callers as an optionally configured call feature. Of course, as soon as the code had the ability to play music, there was a general request and obvious concept that Asterisk should include a few default music-on-hold files. At that point, several people within Digium looked around at the possible files we could use, but all of them had some type of license issues, which is understandable.
We found a company which sold rights to music, and we discussed in specific, painstaking detail what we wanted to do with the files and how they were going to be used. They agreed that we could do what we wanted and distribute the files with Asterisk and that they were able to provide to us the appropriate license, so we paid our fee and proceeded to pick some likely music.
We then included them in Asterisk in the hopes that the community would find them useful as part of the system without having to search out selections which complied with various copyright issues. This was a good-faith gesture on our part, and we had a quite reasonable expectation that the vendor from whom we purchased the license was authorized to provide to us a global right-to-use and redistribution capability to the Asterisk community for these sound files.
Apparently, that assumption is now being questioned. In some nations (Australia and France, to pick two that have been brought to our attention) there are some who are claiming that we do not have the rights outlined above, and that our users therefore are in a similar situation where they may be in violation of license terms.
What's interesting here is the contrast between the software side, and its well-established open source licences, and the media side, which is still a hodge-podge of inconsistent schemes:
In the interests of space here I will not outline the exact organizations, laws, and claims in question. Suffice it to say they are complex and unclear with a broad range of possible interpretations. Currently, at least two organizations disagree that we are complying with a set of license terms. This is very far outside of Digium’s ability or interest to manage, nor do we wish to become involved in the protracted series of legal proceedings required to sort out this licensing issue.
Simply eliminating the files completely is hardly optimal for Asterisk users, so Digium has come up with a rather better alternative:
The new music we’ve included is under the Creative Commons 2.5 license – which quite frankly didn’t have much of a following for media back when we first were looking for a set of MOH files. Certainly, the selection of good-quality music files that would suffice did not exist in an easy-to-obtain fashion, or we would have gone this route in the first place.
Hopefully you’ll like the new music on hold, and will be customers of the artists who have so graciously given their work out under such a reasonable license. We found the new music on Opsound for those of you who are looking for an even wider selection of freely available music.
I'd not come across Opsound before, but it sounds rather interesting:
Opsound is a gift economy in action, an experiment in applying the model of free software to music. Musicians and sound artists are invited to add their work to the Opsound pool using a copyleft license developed by Creative Commons. Listeners are invited to download, share, remix, and reimagine.
Anyone is encouraged to contribute sound files to the Opsound's open sound pool.
Opsound enjoys open-eared listening, including field recordings, ambiences, incomplete improvisations, monologues & dialogues, unfinished experiments, detached soundtracks, vocal solos, strange noises, bedroom laptop, microsound, generative, glitch dub, idm, minimal techno, blip hop, hip hop, turntablist, downtempo, uptempo, reggae, ragga, raga, roots, breakbeat, basement punk, garage band, indy, shoegazer, psychedelia, noise, song, be-bop, free jazz, modern composition, avant-anything, etc. Sound files can be complete pieces of music, or elements intended be combined into something new.
All material for the sound pool will be released under a Creative Commons license (the "Attribution-ShareAlike license"), a copyleft license in the spirit of open source software license which allows for all kinds of copying, remixing, use, and reuse while retaining an attribution to the original artist.
Opsound is a good demonstration of how the ideas behind free software are being applied in other fields, with the result that open source projects like Asterisk can then benefit in its turn – sharing as symbiosis.