Over the past year, the FCC has quickly ruled that any VoIP calls attached to the PSTN have to:
- Allow wiretapping on their systems
- Support emergency 911 calls
- Pay hefty fees into the Universal Service Fund to support poor and rural areas
I came to VON this year to find out how companies are reacting to the new regulatory requirements, as well as what they’re doing to grow up in other ways: offer better security, allow vendors to measure performance and quality, and so on. VON is an increasingly popular show, expecting between 9,000 and 10,000 attendees this year. There was plenty for them to look at.
Peering and interconnection with the PSTN
I chose to interview CommPartners because they went through the difficult two-and-a-half-year process of becoming a competitive local exchange carrier (CLEC) so that they could ensure access to traditional phone customers. CLECs sprung up like dandelions after the passage of the 1996 Telecom Act, but most fell afoul of various blocking behaviors by the incumbent phone companies, or could not compete for other reasons.CommPartners found that both the phone companies and the regulators had trouble handling its application for CLEC status, because no one had tried to do it for so long. Now they’re approved in 48 U.S. states and pending in the other two. They offer wholesale service to VoIP providers from four access points in major U.S. cities.
Being a VoIP company is much, much easier than the traditional CLEC, because CLECs who run physical lines to the homes have to colocate equipment in the central offices and access points of the incumbent companies–and then has to fight for access to their own equipment. CommPartners, in contrast, just has to string a wire to the incumbent phone company sites; its costs are a fraction of those incurred by a traditional CLEC.
They can meet all regulatory requirements, as well as customer needs such as number porting (small business customers don’t want to change phone numbers when they sign up for a new service). They can obey FCC rules for CALEA-style wiretapping by capturing traffic as it passes through their four access points. They contract out 911 emergency service to vendors who specialize in it. They pay into the Universal Service Fund. Nevertheless, their avoidance of certain taxes saves them at least 15% in pricing.
Currently, they offer only voice applications, but their adoption of Linksys 1 routers allows them to add sophisticated applications in the future. They don’t see videoconferencing as being important in the business market for some time, but the use of video for surveillance may be a good market.
Peering among VoIP providers has become popular over the last couple years, in the hope of avoiding the PSTN. Although each pair of VoiP providers could set up their own peering agreement, it’s obviously more efficient to create rules for peering and allow multiple VoiP providers to join a consortium. Two of the better-known peering consortia are the Voice Peering Fabric formed by Stealth Communications and the XConnect network.
Once a peering agreement has been reached, VoIP providers also need to be able to find the IP address that corresponds to a given phone number. The IETF set up a system called ENUM which seems to be taking off. It’s conceptually like the in-addr.arpa domain used in DNS configurations to support reverse DNS lookups: a hierarchical arrangement of phone numbers mapped to addresses.
To allow VoIP providers on different peering networks to find each other, a non-profit group called the Spider Registry recently set up shop. Quality of information (that is, providing the right IP address for the phone number) is in the hands of each VoIP provider who registers.
911 services
One of the thorniest problems in VoIP is attaching someone to the appropriate emergency center (a public safety answering point, or PSAP) when the user dials 911. Landlines are easy to direct to the right PSAP, of course, and mobile phones can figure out the location of the user through his location in the cell. For VoIP, it’s more of a hack.I got one solution from Intrado, one of the many companies that have entered this space in recognition that the FCC was going to hold the VoIP industry responsible for solving this problem. Intrado has a network connecting it to all the PSAPs in the areas it serves. It is also connected to another critical element of the 911 solution, the Master Street Address Guide (MSAG).
The role of the MSAG is as follows. We’re used to entering addresses in any sort of casual format we want, with St for Street and so forth. But PSAPs have to make sure to have the right address, so they require that the phone company pass it to them in a canonical format stored by the MSAG. Phone companies resolve their users’ addresses at the MSAG so they have the right format when the emergency arises.
The user himself plays a key role. When he connects to the Internet, he is supposed to enter his current address. This means that a mobile user must enter the address whenever he opens his device in a cafe or workplace. Because the owner of the access point knows the address, this owner could in theory fill it in and save the user this trouble. The information goes to the phone provider, who has contracted with a 911 service such as Intrado to get the official MSAG address and then, when 911 is dialed, to send the relevant information as well as route the call itself to a PSAP.
Performance analysis and quality control
Measurement systems monitor your network while it’s in operation, allowing troubleshooting as well as long-term collection of performance information. Troubleshooting may identify a serious problem like a failed router in the network. More subtle, long-term performance problems usually have to be fixed by increasing capacity.Certain measurements are common and easy to evaluate: data rate and packet loss. But it’s hard to find measurements that correspond to more subtle aspects of the user experience, such as voice or video quality.
Telchemy founder and CEO Alan Clark boasted about his contributions to IETF specifications, saying that his company takes the standardization of measurement and performance seriously. Standardization, of course, means everybody would know they’re talking about the same things when measuring performance, and can compare results found by products from different companies.
I talked to Ofir Michael at RADCOM, which offers measurement platforms that you can physically install on the network, as well as software that can be installed on ordinary PCs to do the measurement. A wide range of measurements can be taken, including jitter (which can be described as the unevenness of data transfer) and bursts of data (which is related to jitter, but involves the filling of buffers that are supposed to prevent jitter).
Security
Email spam filters are based on intensive research on the content of unsolicited mail and peculiar ways it uses the SMTP protocol. Spam over Internet telephony (spit) has to be fought with slightly different tactics, because its voice content cannot be examined in the same way as the text of email. And like email spam, spit goes through a continuous battle where both the producers and the filters upgrade their techniques.According to David Schwartz of Kayote Networks, some of the ways to recognize spit include checks for:
- A series of calls to a regular range of IP addresses (which may or may not be in order, depending on how sophisticated the spammer is)
- Multiple calls in a short period of time from a single origin
- Calls where the recipient hangs up immediately
- Numerous connection requests of exactly the same size
I also stopped by the booth of BorderWare Technologies, which has enhanced their firewall to perform filtering for voice calls. SIP requires application-layer processing that traditional firewalls can’t do, as well as special handling across NAT. BorderWare supports white lists and black lists, as well as rate limiting to help prevent denial-of-service attacks.
Video on the Net
Jeff Pulver made video the centerpiece of VON this year. He has pulled together a site called Network 2.0 to show off the many video sites on the Internet. Pulver was enthusiastic about the potential disruptive effect of these grassroots providers on Hollywood and television. He told us to forget about the legacy of old films and television shows: “Anything that existed before is all screwed up. On the creative side, understand that things have to get better.”In other words, copyright controls will prevent old material from taking advantage of the Internet’s creative and distributive potential, but new creators will recognize the value of sharing and will release their work under licenses that allow it.
Of course, the established media are not asleep. Right after Pulver’s keynote, AOL vice chair Ted Leonsis put us through an adrenalized display of mainstream TV, movie, and pop music on the Internet. It looks like AOL is shifting considerable resources to online videos (resources that I expect will come out of advertising on traditional channels). Leonsis’s talk also suggested they are hoping to insinuate their leading offerings into the daily habits of young people more interested in the Web than in the boob tube. The Open AIM platform is supposed to let developers extend AIM.
It was amusing to see all the effort AOL was putting into achieving the informal, almost impulsive feel that we associate with much material on the Internet (the blogs, the amateur videos, and so forth) when AOL’s means of generating the material was just as planned and staged as anything else pop idols do.
I can’t fail to mention that Apple announced its video download service during the week of the show.
Ultra Wideband developments
I talked to Tom Houy of CSR about Ultra Wideband (UWB), which has been through tough times in standards committees. They think the specification for Bluetooth with UWB will be approved in mid-2007 and that they will offer a product at that same time. They also think they can offer speeds of over 400 Mb per second, close to the speed in the spec.CSR’s approach to UWB is to run Bluetooth over it. This offers several advantages.
First, Bluetooth is supported by lots of devices and applications that don’t yet support UWB. By combining them, CSR’s chip will let devices and applications take advantage of the fast UWB connection when they can, and fall back on the slower Bluetooth when UWB support is not available. UWB will be available immediately to applications that were built for Bluetooth.
Other companies
TensorComm talked to me about their Interference Cancellation Technology, which basically makes CDMA phones cleaner and higher-performing. I didn’t even attempt to delve into the mathematics of radio wave signal processing that makes this possible. The idea is that current CDMA allows a phone to pick its signal out from multiple signals being transmitted by the base station in the same frequency range, but leaves the other signals there as background noise. Interference Cancellation Technology substantially eliminates that noise. Advantages include:- Fewer dropped calls.
- Listeners can hear better.
- Cell phones can pick up their signals further from the base station.
- Base stations need to expend less power per phone call, and can use the remaining power to support more users or higher data transfer rates (up to 60% higher).
Talking to David Mandelstam of Sangoma Technologies was refreshing because of his praise for old-fashioned values. While he liked to boast about his product (a board that turns low-end systems into robust routers that can support voice and video) as much as any other CEO, he repeatedly claimed that his company was doing nothing brilliant or clever, just investing the time and money to create a solid product. They went through a total redesign two years ago, and were careful to code well and use good hardware. Thus, their systems can stay up indefinitely (he cited a MTBF of a million of hours) under conditions that would break competitors’ systems.
There were plenty of other topics at VON. For instance, network neutrality (about which I have written extensively in February, in May, and in June) was widely discussed. Like all new businesses on the Internet, VoIP providers are worried that incumbent phone companies will use differential service to cut out innovative competition. Because Congress and the FCC have declined to step in, we’ll probably be able to see how VoIP providers are dealing with phone company service by Fall VON next year.
