Voice over IP (VoIP) can provide huge savings on your phone bill by allowing you to utilize an IP network to make calls as opposed to the traditional telephone public switched telephone network (PSTN), also known as Plain Old Telephone Service (POTS). Many organizations today utilize wireless IP networks. As a result, it’s possible to run VoIP applications over Wi-Fi, too. However, you must be aware of a number of potential pitfalls when planning a “VoIP-over-wireless” (often called VoW, VoFi, or wVoIP) deployment.
With WiMAX invented for longer range Wi-Fi communications, wireless carriers are offering hybrid phones that will use VoIP over Wi-Fi when a Wi-Fi network is available and switch to cellular when one is not. So VoIP over wireless encompasses different things, depending on the context.
Here are some things you need to know about wireless VoIP.
#1: Wireless VoIP offers advantages over cellular service
A big advantage of wireless VoIP is that IP phones that work on Wi-Fi networks can be used in place of cell phones in many cases. Public 802.11 hotspots are usually free or available at a very low daily cost.
#2: VoIP over wireless LAN has many uses
Using VoIP over a wireless network can provide easy internal calling for companies, campuses, hospitals, hotels, government buildings, and multiple-tenant units such as dorms, with the ability to roam freely and advanced calling features such as voicemail and caller ID. Users can also use the network’s Internet connection and an account with a VoIP provider to make calls outside the site, including domestic long distance and international calls, generally at no extra charge.
#3: WiMAX extends the reach of VoIP
WiMAX is a long-range microwave-based wireless technology based on the 802.16 standards. WiMAX has the ability to provide wireless broadband coverage to an entire metropolitan or large rural area, as WiMAX transmissions can span up to 75 kilometers. With throughputs ranging between 70 Mbps and 288 Mbps, WiMAX certainly has the bandwidth to support VoIP.
#4: Voice transmission is more sensitive than data transmission
VoIP is a real-time application, making it particularly sensitive to packet loss that can be caused in a wireless network by weak signals, range limitations, and interference from other devices that use the same frequency. To support VoIP, your wireless network needs to be reliable as users anticipate better dependability from their phone systems over their computers. They expect a ring tone each and every time without any dropped calls as well as high voice quality.
#5: Mixing VoIP and data can degrade call quality
Because of the sensitivity of VoIP applications to any disruption or delay, competing with data transmissions on the same wireless network can cause degradation of voice quality. It’s important to implement quality of service (QoS) features to ensure that VoIP packets get priority.
#6: Security is a Much Larger Concern Over Wireless
Security is a major concern for VoIP, as sending phone calls over a public IP network presents more security risks than utilizing the proprietary “closed” networks of the telcos. Wireless technology adds another layer of security concerns, with transmissions going over the airwaves instead of cables and thus subject to easier interception. Common VoIP protocols such as SIP have their own security vulnerabilities.
Any Wi-Fi network that carries VoIP traffic must be secured, as such traffic should always be protected by authentication and encryption.
On the flip side, many of our telephone calls already travel over airwaves, on cellphones.
#7: Older Wireless LAN Equipment Isn’t Quite Ready for VoIP
If your intent is to deploy VoIP over your existing data Wi-Fi network, you may be sorely disappointed. For good performance, especially in the enterprise space, you need to have wireless LAN hardware and software specifically designed to work with voice traffic, as well as address the prioritization and security issues.
Seek integrated support for SIP and policy-based management that allows you to block unauthorized voice traffic.
#8: Wireless VoIP Equipment is Available at Consumer and Enterprise Levels
Many popular vendors of consumer-level networking equipment (LinkSys, D-Link, Netgear) now make IP phones that work with their wireless routers. For example, D-Link’s DPH-540 IP phone supports all SIP-based VoIP providers and works with 802.11b or g Wi-Fi networks. It supports WEP, WPA, and WPA2 encryption. At the same time, vendors of enterprise-level hardware like Cisco offer IP phones that work with IP PBX systems. For example, Cisco’s Unified Wireless IP phones CP-7942CG, CP-7961CG, and CP-7962CG work with the Cisco Unified Communications Manager and supports EAP-FAST authentication for higher security.
#9: VoIP over wireless smart phones can save companies money
Nowadays, many business people carry smart phones. These phones are provided by cellphone carriers, and utilizing the telephone capability costs precious minutes. International calls of course call extra.
However, by installing Skype for Mobile on these devices or utilizing other methods that take internet data over phone minutes, users can make free or extremely low-cost phone calls while bypassing the cellular plan and using the phone’s Internet connection, or in the case of Wi-Fi enabled devices, using a wireless hotspot.
#10: Future phones will combine cellular and Wi-Fi VoIP
Industry leaders predict that the next generation of cell phones will all include built-in Wi-Fi. With these hybrid or dual-mode phones, you’ll be able to seamlessly switch between cellular and VoIP over Wi-Fi when you come into range of a Wi-Fi hotspot, even within the same phone call.
Landlines are expected to all but disappear as hybrid phones become a singular solution for telephony, operating off the user’s Wi-Fi network at home and using cellular technology when there is no Wi-Fi network within range. This is predicted to lower the total cost of telephone service.
About Network I.T. and Cisco IP Wireless Phones
In addition to Network IT buying used Cisco IP phones, it also offers the following used Cisco wireless IP phones for your business:
- Used Cisco CP-7961G
- Used Cisco CP-7942G
- Used Cisco CP-7962G
Network IT is located in Toronto, Ontario and ships throughout Canada and the US. Contact Network IT today to get a free quote on Used Cisco IP and Wireless Phones today.