Services, like software, run the gamut when it comes to cost. Free services, such as PhoneFree, which allows you to make free PC-to-PC audio or video calls, are geared toward consumers and often don't work behind a firewall. There are a large number of companies offering business-grade VoIP services, such as ICG's VoicePipe. Another player, Vonage, offers both residential and small business plans with unlimited domestic long distance for $39.99 (£25) per month and low per-minute international rates. You will typically need special software and/or hardware, provided by the service provider, to use these services. A VoIP service generally allows you to forego the steep upfront cost of investing in professional-grade software or hardware products, and since some services are available on a free trial basis, you can try them without risk. Using a service might be preferable if you don't have the onsite technical personnel to maintain hardware or troubleshoot software problems. VoIP hardware devices
Hardware solutions tend to be the most costly way to implement VoIP, but they are often easier to configure than software solutions, and owning the hardware allows you more control than subscribing to an outside service. VoIP hardware devices generally include:
- Analog-to-digital phone converters such as the Cisco ATA 186. You plug a standard telephone into the adapter and its analogue signals are digitised for transmission over IP.
- Integrated IP phones, such as Nortel's 12004 Internet Telephone, Cisco's large line of IP phones, and Adtech's SI-160 IP Phone, which includes a smart card reader for added security.
- Gateway devices, such as those developed by RADirect, which use a transport technology called TDM over IP to extend T1 and T3 transmissions across IP networks; MultiTech's MultiVOIP gateways, which support both SIP and H.323; and Cisco's carrier-class VOIP and Voice over ATM (VoATM) MGX 8000 Series Gateways.
Some hardware devices may also require that special software be installed on the network (for example, many of Cisco's VoIP products require that Cisco's Call Manager software be installed). Many of the hardware devices are compatible with various VoIP services. Tip
In addition to dedicated VoIP devices, some routers -- such as the Cisco 3600 series -- can be configured to transmit voice over the IP network.
Some devices do not require a computer on either end. For example, D-Link's i2eye video phone transmits both voice and video over a DSL or cable connection when you plug the device into a standard telephone and TV, using the H.323 standards (you need the same setup on both ends). More improvements to come
Voice over IP is finally coming into its own. As transmission quality and reliability improve, managers should recognise the significant cost savings of using their Internet connections and IP-based LANs for voice communication instead of paying high Telco charges. The future promises more improvements, with newer, easier-to-use protocols such as SIP and wireless VoIP already gaining ground. However, it's not easy to choose from all the VoIP solutions that are available -- and the situation promises to only get more difficult in the future as more and more software companies, hardware vendors, and service providers jump into the game.
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Talkback
Hi; what kind of deal / package have you to talk pc / phone, or whatever from the British Virgin Islands to the U.S. or vice - versa ?
The Cable & Wireless co. there has BLOCKED companies from doing pc to phone. Thanks.
Peace ----------------------- Mike Burke