The convergence of data and voice networks in the business environment takes on a new twist with the emergence of wireless networking. The freedom of mobility offered to users in a wireless LAN has proven to provide a noticeable boost in productivity, efficiency, and. employee morale. No longer is the work force tied to their desk when on the job. Workers can access company files and receive important communications from anywhere on the company campus that is in range of a wireless access point.
With voice communications thrown into the mix, mobile users can stay in touch while roaming the property inside or out, and even on the road. The acceptance of the fixed to mobile convergence concept by the telecommunications industry only promises to fuel the fire for the adoption of VoIP over WiFi.
The Challenges of Implementing VoIP over WiFi Networks
As with any emerging technology, there are challenges to overcome. The development of the converged network, i.e. data and voice on the same IP based LAN, while yet to be an established norm, is proving to be beneficial for businesses from both a cost and productivity perspective. Adding the prospect of VoIP over a wireless network brings up a whole new set of issues.
VoIP is a time sensitive technology. Calls must be set up and authenticated, and voice packets must arrive at their destination without interruption and on time. This requires a near continuous network stream, uninterrupted by less sensitive data transmissions. The implementation of Quality of Service techniques on wired LANs assure that these voice packets receive priority, and call quality issues such as latency, jitter, and packet loss have been sufficiently addressed.
Enter the standards based wireless network, a technology in an earlier stage of development, and more challenges occur. While today’s wired network provides plenty of bandwidth for both voice and data to coexist, WLANs provide less bandwidth, and Quality of Service issues must be revisited. Security measures such as authentication and encryption must be implemented and can add to the problem by increasing the size of the voice packet. Additionally, users on the move will traverse wireless access points where handoffs must be quick and smooth.
The IEEE 802 standards governing wireless technology are evolving rapidly and promise to deal with a broad spectrum of WiFi issues. Increasing the bandwidth available, prioritizing voice packets for QoS, authentication and encryption protocols for security, and enhanced roaming techniques are all being addressed.
Also in development is the wireless technology commonly known as WiMax, providing for the implementation of high bandwidth wireless communications covering distances of up to 30 miles. The evolution of WiMax could prove of great consequence to developing countries, as well as Metropolitan LANs.
Security in a VoIP/WiFi Network
Companies wishing to implement wVoIP must take security issues into consideration from the start. As in any IP network, the dangers of hackers, denial of service, highjacking and spam, all lurk in the shadows.
Because a wireless network uses radio frequencies as its transmission media, the security normally provided by a firewall in a wired network is not sufficient, simply because of the physics. Whereas to break into a wired LAN requires hackers to either physically be inside the network or to hack in through the Internet, in a WLAN they can grab network transmissions from the air while parked across the street. The security issues that network managers must consider in a VoWLAN are the privacy of conversations, and the protection of the network infrastructure.
For WiFi networks, security has had a shaky start with the implementation of WEP as its security mechanism. WEP provides for authentication and encryption between the user and the access point, and was found to be easily hacked. The 802.11i standard, adopted as WPA2 (Wireless Protected Access), provides for more robust security by requiring two way authentication between the user and the network, and uses AES (Advanced Encryption Standard) as its encryption engine.
As network managers plan the rollout of a wireless VoIP network, the greatest security threat they face is improper implementation. Building security into the design of the initial deployment can, and should affect the network topology, as well as material costs. Failure to do so could lead to further expenses in loss of services and network redesigns in the event of compromise.
WiFi, VoIP, and the Cellular Networks
Manufacturers of cellular devices are incorporating WiFi radios into their handsets at an ever increasing rate. New versions of mobile operating systems are coming out complete with a built in VoIP stack, inviting carriers and manufacturers to add VoIP functionality to their devices. Dual and Quad band cell phones can choose between the strongest network available, cellular or WiFi, and place a call accordingly.
As cell phones become more like mobile offices, the benefits of a mobile work force become apparent. In the case of the road warrior, the ability to communicate via email, text messaging, video or voice, allows them to stay on the road longer without losing touch. In the age of instant information, mobile office applications allow files to be downloaded, edited, and uploaded, increasing the productivity of the traveler to the point where just about anything that can be done in the office can be done on the road.
A cell phone that can switch between cellular and WiFi networks can significantly reduce telecommunications costs at the corporate office. With WiFi hotspots popping up at hotels, cafes, and corporate LANs across the globe, mobile workers can stay in touch with office and family both on and off the job. With the addition of a VoIP service provider, cheaper VoIP calls can be made from any WiFi network at the push of a button.
Imagine, if you will, a future where one phone, with one phone number, can seamlessly traverse cellular networks, WiFi networks, cable and PSTN landlines. Where roaming and switching between disparate networks occur without interruption or loss of call quality. Fixed Mobile Convergence is the buzzword of the decade, and the IP Multimedia Subsystem (IMS) architecture is the standard that promises to get us there.
The goal of IMS is to provide all the services and applications that the Internet provides, both current, and as of yet unimagined. IP based services such as VoIP, Push to talk cellular (POC), videoconferencing, text messaging, community services, presence information and file sharing, are just some of the possibilities. Designed to work with any fixed, mobile or wireless packet switched network, backwards compatibility for the legacy circuit switched phone system is provided through the use of gateways.
Although still in its infancy, IMS is already being implemented by AT&T as the platform in it’s newly acquired Cingular cellular network. Interest in investing in a new infrastructure by mobile and fixed operators has been up and down, as they weigh the costs and benefits of the new technology.
As the technology of VoIP over WiFi networks continues to develop, businesses of all sizes can reap the benefits of increased mobility, productivity, and significant cost savings. Standards committees are constantly working on ways to increase security and quality of service, and as fixed mobile convergence gains acceptance in the telecommunications industry, more choices in the services offered and the IP applications available to businesses are sure to follow. What will also be interesting to watch, is how these very bandwidth intensive applications will be priced by the carrier networks, and how it will affect the neutrality of the Internet.
By: Michael Talbert
Posts Tagged ‘Telecommunications Industry’
VoIP Over WiFi for Businesses: Sending Voice Over the Wireless LAN
March 19th, 2010VoIP – A Destructive Technology
November 1st, 2009
Many in the telecommunications industry have described the upsurge in the use of VoIP as being destructive. This is true in so far as the traditional landline services have been disrupted. Telecom Companies services such as BT have had to introduce their own VoIP packages for new subscribers and for those existing ones who require the facility, albeit these are mainly unaware. This highlights the concern the landline suppliers have over VoIP.
The backbone of the VoIP technology requires the use of broadband. As faster DSL broadband delivery has been made available, the growth of VoIP users has increased exponentially. The traditional Telecom Companies who had the lion’s share of the market have had to readjust and compete with the likes of Vonage and Skype. A revolution has taken place which has allowed for increased competition and even the smaller Internet providers or other Internet-based companies have captured large segments of the Telecom market at the expense of the once huge Telecom cartel.
Within the VoIP industry one clear pattern is emerging, that is there is no clear pattern. The niches within the technology allows for a huge combination of methods and/or alternatives which allow the use of voice over internet to take place. Whereas some of these sub niches claim a meteoric rise in popularity, they are as likely to face a sudden fall in popularity. Take for example Vonage, having been at the forefront of the technology their overall percentage share has fallen dramatically with the rise of Skype and usage of VoIP through social media.
Time will tell to see whether they can withstand this and establish a method of using VoIP as being the most trustworthy and only real alternative to traditional landlines. It is interesting therefore to note that the Telecom Companies have now taken on board similar methods and BT Broadband send out their ‘hub’ allowing connection to PCs and other broadband devices. For the ordinary user these terms are confusing to say the least but it suggests an acknowledgment that this is the way of the future and that eventually all traditional landlines will be done away with.
Companies such as Vonage and Skype, providing they offer a set up which replaces the normal telephone with like for like, should have nothing to fear and these will eventually compete on a more even footing with their larger counterparts.
By: Jonathan Ledger
Choosing a Broadband Connection for VoIP
October 8th, 2009
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 Telco’s 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 company’s local switching station, the more signal degradation you will have, and the maximum distance is 18,000 feet. Telco’s 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 Telco’s seem to think they need to get the money where they can.
In January ’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 you’ve 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, Telco’s, 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. Test your broadband connection for VoIP suitability at [http://www.testyourvoip.com] .
By: Michael Talbert
