While not absolutely necessary, a broadband Internet connection is what makes your Internet phone calls reliable, and understandable. VoIP uses a traffic engineering term called Quality of Service (QoS) that refers to the implementation of controls to ensure that delay sensitive IP packets are prioritized as they flow through the pipe. To forgo these controls would result in acoustic problems like jitter and echo, as well as dropped calls.
Because a broadband pipe is much larger than a dial up connection, there is much more throughput capacity, or space, to allow us to prioritize. There are basically three ways for the residential consumer to obtain a broadband Internet connection. From your cable television provider, your telephone company, or a wireless broadband network such as Clearwire, a Wi-Fi hotspot, or even a cellular network likes Verizon or Cingular. With these options becoming increasingly more wide spread, utilizing the Internet to route your phone calls has also become a viable and cost saving alternative to traditional landline telephony. Now the question becomes, which type of broadband service is best suited for voice over Internet protocol.
Since the advent of cable television, cable companies have contributed enormously to the development of the worlds Wide Area Networks (WANs), adding broadband Internet to their list of services offered. Indeed, with the development of VoIP, they have even blurred the lines of the telecommunications Industry. The cable modem, and its Coax Cable pipe, have ushered the Internet into the Jet Age with Internet service at the speed of light. A cable company WAN consists of neighborhoods connected to nodes, each node having its allotted amount of bandwidth. The cable pipe is about the largest to be had for the residential consumer and is plenty big enough for the clearest of VoIP phone calls.
However, the bigger the neighborhood grows, and the more people that connect to the pipe, the less bandwidth is available for each household. Cable companies are generally very good about distributing bandwidth and will add more nodes when necessary. Their network is, after all, their bread and butter. Just be aware that at peak traffic times, VoIP call quality can degrade. The Digital Subscriber Line, or DSL, is the residential broadband solution offered by the traditional telephone companies such as AT&T, the regional bells, and others like Quest Communications for example. For years the Telcos have had the upper hand in the business community, connecting their networks to the outside world via a T1 line, which is the equivalent bandwidth wise to a cable modem.
DSL is somewhat slower than a cable modem, and in fact, in some communities is offered at 2 speeds. It also tends to be somewhat cheaper. Nevertheless, there is still ample bandwidth to implement VoIP successfully. DSL is not affected by node saturation like cable networks, but it is distance sensitive. The further you are from your telephone companys local switching station, the more signal degradation you will have, and the maximum distance is 18,000 feet.
Telcos can and do use remote switching stations to expand their service where they see a market opportunity. The fatal flaw of DSL when considering the use of VoIP, is that most companies require you to subscribe to their traditional telephone service as well. Naked DSL, the unbundling of broadband and telephone service, is possible and is offered by only a few local phone companies.
Perhaps because of the cable companies creeping onto their turf, and the slow but sure acceptance of VoIP in the general population, the Telcos seem to think they need to get the money where they can. In January of 07, the Senate reintroduced the Internet Freedom Preservation Act. One of the provisions called for, is that all broadband service providers offer consumers standalone broadband service. If this Net Neutrality bill passes, DSL could prove to be a viable option for those wishing to switch to VoIP. Wireless networks also provide ample bandwidth for VoIP telephony, and their value is most appreciated in the life of the Road Warrior. People who constantly travel, weather for business or pleasure, are finding Wi-Fi hotspots popping up everywhere.
Most modern hotels have their own wireless network, and Internet cafes are becoming an international phenomenon. Travelers that find a hotspot have the choice of using their laptop and a headset to communicate over the Internet, or to use one of the many Internet Phones found on the market today. Metropolitan Wireless Broadband networks are also proliferating nation wide.
Clearwire Wireless Broadband is a company that uses a combination of Non Line of Site (NLOS) and its own proprietary technology to cover whole cities, even regions of the country. Let it be known however, that this technology has been met with mixed reviews. If youve visited a college campus recently, you may have noticed tiny antennas sticking up from the rooftops every few meters. Campuses today have their own Wi-Fi networks, allowing students, faculty and administrators to make VoIP phone calls via their laptop, or an Internet phone, from anywhere on campus. The Cellular Networks built by companies like Verizon, Sprint, and Cingular, have proliferated all over the world and indeed blanket most developed population areas.
Cell phones have been introduced by Nokia, Samsung, and most recently the Apple iPhone, that are capable of switching (in some cases seamlessly) from a cellular network to a Wi-Fi hotspot and back. However, it is the Cellular companies that control the airwaves. Cingular Wireless (soon to be at&t wireless) already utilizes phones with quad band and Wi-Fi support, and will be the carrier for the much anticipated Apple iPhone.
While the cell phone networks seem to have been dragging their feet on implementing full support of VoIP for the consumer, there are technological issues to be considered, as well as how they will profit from the technology. Once the broadband pipe has been decided upon, there is still the issue of picking a VoIP service provider. Cable companies, Telcos, and increasingly cellular companies all offer their own VoIP service to consumers, and since their service is over their own networks, they are in an excellent position to deal with Quality of Service issues.
You are not, however, under any obligation to use your broadband service provider as your VoIP service provider. Pure play VoIP providers, companies that offer only VoIP service, have grown in number, and could be said to be responsible for the low rates associated with VoIP telephony. Vonage, with around 53% of the residential VoIP market, is one pioneer in the industry that offers calling plans as low as $15 a month.
SunRocket, Packet8, and the peer to peer VoIP company Skype, have calling plans for even less. Cable and Telco plans on the other hand, are bound to cost more, starting at around $35 or $40. Whatever VoIP service provider you choose, and for whatever reason, the most important factor in determining the quality of the call is the quality of the pipe. To test your connection for VoIP suitability, do a query on the keywords "voip test" on your favorite search engine.
Author Michael Talbert is a certified systems engineer and web designerwith over 7 years experience in the industry. For more information on Voice over IP Telephony, visit the website VoIP-Facts.net, or the VoIP Blog for up to date industry news and commentary.