February 22, 2006

FON, AUPs, ethics and practicalities

FON has had an upsurge of publicity lately, in the US at least, following an article in the Wall Street Journal, and funding from Google. The article more deals with the ethics involved in bloggers recommending a product without disclosing their interest in that product. But the article also put the concept of sharing Internet connections over WiFi in a more mainstream light.

Many bloggers commenting about the FON concept have focussed on the business model. FON encourages it's users to share their wired (DSL/Cable) Internet connection through their FON-enabled router. Many have criticised FON saying that it's business model is dependant upon it's users violating their respective ISP's Acceptable Usage Policies (AUP).

To these critics I ask - why cry foul? An ISP may have an AUP in place, but can it really claim to own the bandwidth after it has been paid for by the customer? There are various technical means that the customer can use to hide what's really going on on his side of his modem. So what use is an AUP if violations can't be easily detected?

The way I see it is, an ISP provides Internet bandwidth to the customer, and receives money in return. Bandwidth is a finite resource. If the customer chooses to share it with his friends or neighbors, isn't that the customer's problem? By sharing it, there is less available for his own use.

If the ISP has a problem with that, why do they market their service as "unlimited"? To sell a service as unlimited, then place limitations on it is unethical. Historically, I believe that people have compled with their AUPs simply because it takes an effort to not comply. Previously, sharing your bandwidth with your neighbors has taken a bit of knowledge and time - and not everybody had wireless routers. These days wireless networking makes it incredibly easy to share your bandwidth.

ISPs have to wake up to this fact and use it to their advantage. They need to learn the lessons of the P2P wars between file-sharers and the RIAA. The RIAA is public enemy number one amogst much of the music-consuming public because the RIAA has been consistently treating it's potenial customers as potential criminals. The RIAA has been largely opposed to change in their business model, despite the fact that technology advances have been steadily rendering their old business model irrelevant. Being more technology-savvy, I would expect ISP's to rely less on a heavy-handed approach to AUP violations and instead embrace the winds of change.

I respect the concept of copyright and intellectual property. I just don't think that business models, based on the idea that copyrighted works in digital form can be sold as individual units, are viable. I can sympathise with the RIAA. I believe that redistributing copyrighted works without the appropriate permissions is unethical because it potentially robs the artist of a sale. A person can make an infinite number of perfect copies of a copyrighted work without loss to himself. The same is not true for Internet bandwidth. If an ISP's customer shares his bandwidth, he loses a certain amount of bandwidth to whomever he has shared it with. Rather than duplicating the Internet access, the customer has half the level of access he is paying for. This is almost the same thing as a person sharing a CD with his friend - the CD is not duplicated, there is no copyright violation, but both people are able to listen to the CD. This is the choice those people have chosen. The record company can't monitor if people physically share their CDs - and so they don't bother to try. ISPs can be prevented from seeing if people are sharing their access - so why should they bother with AUPs that restrict bandwidth sharing? If people want to share with their friends isn't that their personal choice? AUP or not, is it really practical for an ISP to try to police what goes on on the customer's side of the modem? And if it is not practical to do so, is it then a wise thing to make rules regarding this sort of customer behaviour? I think not.

In the end, the free market should be the final arbiter. If bandwidth-sharing becomes prevelant, I would hope that commercial opportunities exist for ISPs to supply bandwidth to customers who wish to share it. There may not be as much profit in such an exercise, but then, technological change has a way of screwing with people's established enterprises. The freedom of the Internet screwed proprietary networks such as Compuserve. AOL survived by becoming an ISP rather than competing head-on with the Internet. The same choice may now be looming for today's ISPs.

February 06, 2006

What I'm up to

Here's what's going on in my wireless world at the moment.

Firstly, I'm testing improvements to the program called Frottle. I have a WRT54G set up which will eventually be the new router at Melbourne Wireless's Node GHO and I have a test-bed set up of various Linux routers and i386 machines upon which I am testing Frottle.

On the "new" GHO router I am testing OLSR. Testing is more-or-less complete and I have found a crude-but-effective way of gatewaying between OSPF and OLSR - I simply advertise two default routes for the whole Melbourne Wireless supernet into OSPF and OLSR. This will turn Node GHO into a OLSR <-> OSPF gateway. I don't intend this to be a permanent solution - it's not the most efficient way to share routes, but it's a quick and easy way to enable connectivity between OSPF and OLSR worlds. Hopefully people will see that OLSR is much easier to use and will switch over to it in a short period of time.

I'm waiting on the release of the Australian Minitar MNWAPGA Access Point. Minitar, the manufacturer, has openly solicited input from the open-source community on the development of the firmware for this device. When it is released we should have a very nice, very hackable, cheap, small size AP with a half-decent radio. Then the fun will really begin!

January 26, 2006

I'm Back

I'm back.

Here's a couple of articles that really bought my eye:

Advocates of Wi-Fi in Cities Learn Art of Politics

A nice look at the past, present and future of Community Wireless networking in the US and...

Seattle Wireless OLSR Experiments

Seattle Wireless, long time staunch advocates of infrastructure-style wireless networking, are going the Mesh option! And they seem pretty pleased with it.

December 18, 2005

WiMAX Mesh

I saw this post just now. 802.16e, known as Mobile WiMAX has been ratified by the IEEE.

Some interesting features:
  • A MAC layer that supports multiple physical layer specificiations - I guess this is learning from the 802.11b experience where the MAC is fixed to a CSMA/CA access protocol. This led to the Hidden Node problem. It will be interesting to see if any Open Source MAC layer code emerges for WiMAX - being able alter and tweak MAC protocols to fix Hidden Node problems could be quite a good thing.
  • It has an ad-hoc mode - a Mobile WiMAX node will be able to simultaneously act as a "subscriber unit" and "base station". Mobile WiMAX could be used to create a high-bandwidth mesh backbone, sitting on top of a WiFi mesh network. I wonder what sort of MAC protocol will be released for the ad-hoc mode?
  • The Mobile WiMAX spec supports operation in the 2GHz - 11GHz part of the spectrum - meaning it could be used in the "class licence" or unlicenced spectrum.
  • Mobile WiMAX supports MIMO technology - it is able to make use of scattered, multipath radio signals that normally cause interference in non-MIMO radio systems.

Basically, if the above is true, Mobile WiMAX is the best thing for community wireless since WiFi was invented. The main factor now is cost. Will a Mobile WiMAX implementation be released that is suitable for use in community wireless networks? What will the pricing be like? Will Mobile WiMAX use be subject to government regulation in Australia?

Even if Mobile WiMAX is a lot more expensive that WiFi, which it most certainly will be, it will be accessable by community network organisations capable of pooling user's financial resources. A high-bandwidth, outdoor-MAC, licence-free mesh technology would be an excellent backbone for a WiFi mesh network. As WiMAX comes down in cost it could progressively replace the WiFi mesh. But the WiMAX subscriber radio needs to come down in price to directly compete with a WiFi radio before it totally replaces WiFi. We may have WiFi as the last mile for some time to come.

December 05, 2005

MIMO and Mesh Networks

Mesh networks today generally depend on all nodes using omnidirectional antennas. They do so primarily to make setup as easy as possible for the end-users. Directional antennas have some advantages over omnis - they are cheaper on a dollar-for-dB basis, they pick up less interference, and they enable the node-owner to intentionally point high-gain signal beams in an intended direction. However, having to manually point a directional antenna is not suited to mobile nodes - nor does it suit fixed nodes that are intended to be part of a neighborhood mesh. These nodes need to be able to connect to other nodes in any and all directions of the compass. A mesh network takes advantage of any connection opportunity that presents itself - it does not rely on nodes appearing in a location according to a preset plan. So omnidirectional antennas are are the best practical option for meshing.

Enter the yet-to-be-ratified 802.11n WiFi standard with it's Multiple-In, Multiple Out (MIMO) technology and in particular, beamforming antennas on consumer-grade equipment. Beamforming offers the best of both antenna worlds - omnidirectional access with directional high-gain and interference-rejection. Basically, beamforming antennas are electronically steerable. They can direct their high-gain transmission and/or reception beams in any direction they want at any time, without moving parts. They can even block (null) reception of signals from any direction.

The implications for mesh networking are massive. There has already been much adademic research into this possibility - much of it published at the recent IEEE WiMesh-2005 workshop. The big problem for mesh networks today is that a bunch of nodes with omni antennas on the same channel tend to interfere with each other. When any node transmits, every other node in reception range is forced to listen to it. Even worse - a node which within interference range of another node has to stay silent while that node transmits, even though the nodes are not close enough to actually communicate with each other. If these nodes used beamforming antennas, they would not need to stay silent if they were communicating with other nodes - beamforming allows the same channel to be used by many nodes simultaneously, and allows much more efficient routing.

Packets in Ethernet networks can be unicast, multicast and broadcast - in a wired network, the network switch deals with the different kinds of packets and decides if they need to be sent to one, many or every other host (or node) on the network, respectively. In a wireless medium, using omnidirectional antennas means that all packets are broadcast, even if at the Ethernet layer they were intended to be unicast. Beamforming means that unicast packets can be truly unicast, even as they are transmitted via the radio medium.

At the moment, MIMO technology probably isn't quite ready for community wireless networks. 802.11n isn't a standard yet, and a public-access community network can really only operate with a cheap, ratified standard. The various manufacturer's pre-N offerings are quite expensive compared to their 802.11g stablemates, and different manufaturers are offering competing technologies. This makes hacking these devices a fairly fruitless exercise. Also, beamforming antennas rely on the precise placement of multiple antennas - something which isn't easily manufactured or modified in a hobbyists workshop - although we are sure to see hobbyists try. Nonetheless, if 802.11n is ratified with decent beamforming capabilities it could do great things for community mesh networks.

November 28, 2005

WiFi! What is it good for?

Should we put WiFi on a pedestal or chuck it in the bin?

There are many arguments taking place about how the wireless networks of the future could or should operate, and whether or not they could be operated on a non-profit basis. The role of the technology nicknamed WiFi is most often mentioned in these arguments.

WiFi is able to take on some part of the task of delivering a telecommunications service. WiFi is cheap enough that the end-user can afford to buy a WiFi radio outright in a single payment and therefore not have to pay ongoing subscriptions. Because of this, it is often touted as being a cornerstone technology in a future telecommunications system where all bandwidth is provided free of charge and that requires no human administration. WiFi does have it's limits, and just as often as it is lauded, WiFi is derided for it's limitations and we are told that WiFi has no future at all.

Lets look at what WiFi can do, and look at what we expect from our telecommunications system.

A Communications service company can do any or all of these 3 things:

  • Carry large amounts of data long distances between major city exchanges with single, high capacity links
  • Carry medium amounts of data medium distances between suburban or small town exchanges with numerous medium capacity links
  • Carry small amounts of data between suburban exhanges and end users with a vast network of "last mile" links - being copper lines or cell towers.
WiFi is completely unsuited to inter-city data transfer. It doesn't have the range, stability or bandwidth to accomplish such a task. Such a task still requires specialised telco equipment and major infrastructure, so end-users or community groups cannot hope to replicate this service using WiFi.

WiFi has a limited capability to achieve inter-suburb data transfer with fixed, point-to-point links. A network based on WiFi inter-suburb links can service a small number of users, but will become unreliable with too high a bandwidth load. Using WiFi as a point-to-point link system is relatively expensive - a separate radio with a large, high-gain antenna must be dedicated to each end of each link. A node that wants to make multiple links must buy a radio for each link - these costs add up quickly. Also, because of the limited bandwidth in the public 2.4GHz spectrum, there is a maximum number of radios that can operate at the one location - any more and the radios interfere with each other leading to degraded performance and diminishing bandwidth returns.

WiFi is not well-suited to point-to-multipoint links when used at the inter-suburb scale. WiFi was designed for short-range indoor deployments and does not efficiently or fairly manage network bandwidth from the central Access Point when the client radios are beyond receiving range of each other (the "Hidden Node" problem).

There are some proprietary midrange solutions that are within the price range of community groups that could achieve decent inter-suburb point-to-multipoint linkage. Motorola's Canopy system is one such solution. The Access Point cost is around the AU$1100 mark and the client radio is around the $350 mark. These costs are higher than what most end-users are willing to pay. Canopy heralds the widespread introduction of WiMax. It is unclear what impact WiMax will have on the wireless networking landscape. But it is unlikely that WiMax radios will be as cheap as WiFi radios in the short-to-medium term. It is also unlikely that WiMax client radios will offer a peer-to-peer or "adhoc" mode - if it does, the adhoc mode won't be capable of covering the same range as an Access Point. So all WiMax networks will rely on a dedicated central Access Point, and that Access Point will be an expensive piece of hardware - beyond the price-range of the average end-user and deliberately so. Working out a way to pay for Canopy/WiMax Access Points and how to find good places to put them becomes complicated in a non-profit model, but perhaps not impossible for a community organisation. In Australia the fact that the ACMA has some fairly strict rules regarding telco licencing and who is or isn't exempt from buying a licence makes matters even more complicated.

WiFi is best suited to achieve "Last Mile", intra-suburb linkage. WiFi operates best over short distances - the longer the link distance the smaller amount of bandwidth the link can carry. WiFi can cope well with network applications that don't concentrate many users bandwidth bandwidth upon a single node - one such example is Voice-Over-IP (VoIP) telephony. A single WiFi radio is cheap, low power consuming, and physically quite small. With a high-gain omnidirectional antenna attached, WiFi can enable neighborhood connectivity between any users in range of each other. An omnidirectional Wifi antenna is unobtrusive and could easily be mounted on the rooftop television antenna mast on any suburban household. A typical installation would have a minumum rooftop-to-rooftop omnidirectional range of a few hundred metres and a maximum omnidirectional range of roughly 2km, depending on surrounding tree and building heights.

WiFi's usefulness also benefits from the fact that it has a peer-to-peer or adhoc mode, so end-users are also able to act as network repeaters. This effectively makes every node a multipoint-to-multipoint repeater. Network that take advantage of this mode are called mesh networks. There are many successful, real-world examples of mesh networks - both commercial and non-profit. Freifunk.net in Germany and The Champaign-Urbana network in the USA are non-profit examples. Tropos and MeshDynamics are commercial examples. WiFi is a consumer-grade product which hasn't been considered suitable for mission critical applications. Mesh networks increase the reliability of a WiFi network by offering redundant paths that automaticlly bypass node failures or bandwidth choke points. Mesh networks are said to be "self-healing" and "failure-tolerant".

Mesh networks have proven their usefulness, but the technology is still in its infancy. There is yet to emerge a mesh protocol that is truly scalable, yet open-source programmers and academic researchers are refining existing protocols and are learning their limitations. It is only a matter of time before a mesh protocol appears that comes close to the ideal of being globally scalable with little or no human administration or centralised infrastructure. An example on the drawing board that aims to achieve this ideal is DART. However, if and when such a protocol appears, we must still keep in mind the capabilities and limitations of WiFi.

End users continue to pay subscription fees (line rentals) to use a reliable telecommunications service. The advent of WiFi and broadband Internet has opened up the possibility that there may be some way for end users to organise collectively to buy Internet bandwidth in bulk from a central supplier and use WiFi to distribute it amongst themselves - thereby freeing themselves from monthly line rentals. This method of receiving a telecommunications service is acceptable to technology hobbyists and early-adopters, but won't become mainstream until it can deliver a standard of service close to what most users expect from their present telco.

WiFi has its flaws, and it clearly isn't a "magic bullet" technology that can universally deliver everyone's telecommunications needs. But it clearly has it's capabilities, and it has popularised the concept of mesh networking. The idea of wide-area, zero-overhead, zero-admin networking is gaining momentum, and isn't going to go away. The technology can only improve and so with each generation of hardware and protocols we come closer to the ideal.

To telco planners, investors and government regulators: ignore or restrict WiFi at your peril. Networks serve their users best when people are allowed to use them the way they want to use them. WiFi is in the hands of end-users - WiFi can and will be used by them as a Last Mile replacement technology. Acceptable Usage Policies (AUPs) that restrict or prohibit end-users from sharing their bandwidth go against people's natural instincts to organise at a local level to share resources. Telcos that allow end-user bandwidth-redistribution have an enormous marketing advantage and will be seen to be technology innovators in the eyes of the public. Governments that legislate to allow and encourage community-organised data networks also stand to gain political capital - especially in areas that are under-served by commercially-oriented telcos.

November 26, 2005

Internet P2P Pty Ltd

No sooner did I post an entry about P2P Internet sharing does news pop all over the place about a company called FON. They are based in Spain - the company creates a framework that encourages members to share their Internet access with their neighborhood. The payoff is that they either choose to be a "Linus" and be allowed to use other people's Internet, or they can choose to be a "Bill" and get paid for their unused Internet bandwidth. The documentation is mainly in Spanish at the moment so I can't work out the details, but it seems to be some sort of mesh network. The software is a modified version of OpenWRT, and it runs on the Linksys WRT54G. One of the people responsible for the project has posted a more detailed explanation of their buisness model in the OpenWRT Forum.

The people behind the project are negotiating support from ISPs in many countries in Europe and in the USA. I'm very excited about the possibilities of such a project and I'm especially pleased that someone has worked out how to turn community Internet sharing into a (possibly) viable business.

I would love a project like this to become successful. If the concept Internet sharing became widely accepted in mainstream conciousness internationally it would put enormous political pressure on Australian politicians and the ACMA to relax the highly restrictive laws regarding Internet distribution in this country.

Now having said that, I don't think a non-profit community organisation such as Melbourne Wireless should attempt to run something like this commercially. MW could work hand-in-hand with a commercial entity to ensure that commercial users and community users aren't stepping on each others toes. Melbourne Wireless is definitely more of a "Linus" than a "Bill" - and in general the MW membership is of the "Linus" variety. Some MW members have even expressed that should MW ever become "ISP-like", they would leave the organisation. I see a role for a commercial body to play in a P2P Internet sharing project in Australia, but the current community groups are not suited to the commercial role.