VoIP Phones is used with IP telephony for enabling voice communication over the Internet. A VoIP phone or virtual phone uses voice over internet protocol technology for placing and receiving phone calls over an IP network, like the Internet, rather than the conventional public switched phone network. An IP telephone system allows users to place, or receive phone calls on any suitable network as well as to make calls using any IP enabled devices. The analog signal is converted into digital data that are transmitted over the Internet and can be recovered by the receiver in the form of fax, RTP, SIP, or other protocol. The quality of VoIP will depend on the qualities of its underlying technologies and the design of its service providers.
There are two kinds of VoIP phones:
Internet phones and Softphones. Internet phones work just like a regular telephone by using an Internet connection to transmit the call rather than using wires or other means. Softphones are very similar to regular telephones in that they also use an Internet connection and the voice is transmitted over the Internet by means of digital compression (VoIP compression). The major differences between these two systems are the flexibility of using softphones as VoIP phones and the need to buy a separate device for making calls.
Both softphones and VoIP phones are able to transmit voice over IP networks.
The difference lies in the way in which the voice is transmitted. For softphones, there is no session initiation protocol (also known as session control protocol or Session Initiation Protocol). This means that the entire call is made without regard for how long the call is going to be placed, what the time of day is, where the phone is located, etc. There is also no limitation as to the number of calls that can be placed in a single call; there is only a maximum of three calls placed in a given period.
With voice phones, on the other hand, there is a session initiation protocol that is used. This provides rules and parameters for how long each outgoing packet of data is allowed to be spent on a particular call. The problem with this is that this system may be susceptible to malicious interference. Malicious interference may come in the form of malicious software that alters the software in order to alter the way that the phone actually works. If this happens, the voice quality will be affected. Additionally, this type of interference may also result in intentional and unintentional garbling of conversations.
As a solution to this potential issue, some VoIP services are incorporating good security practices into their offerings. This includes application isolation, which ensures that each outgoing packet of data is treated as a unique, special case call and that no one else can interfere with it. Application-level security is typically handled by the Internet Service Providers (ISPs), while mobile operators usually utilize what is known as Wi-Fi security. Another way that VoIP phones are addressing potential security risks is by using what is called a ‘SIP trunking’ application. Essentially, this means that each outgoing packet is assigned an IP address and the IP address is independently checked before being delivered.
In terms of security, some VoIP phones require a PIN code or an activation request (a digital signature). Some VoIP phones require an internet connection so that callers can verify who they are speaking to before the call is made. In some cases, it is even possible for users to speak into their telephone with a special tool that transmits their voice through the telephone adapter to the computer. These features provide some level of security. However, the biggest security risk associated with VoIP phones involves the fact that each call is actually routed over the internet. This means that even if a malicious user could gain access to the IP address of a VoIP service provider’s internal system, they would not be able to affect the contents of any calls made from that IP address.
The big problem with a VoIP phone system is that all of the communications (voice, data, and faxes) are transmitted over the internet, which is not secure at all. Security experts have long suggested that the best way to ensure that all of a VoIP service’s communications are secure is to use an ATA/SIP trunk. ATA stands for Analog Telephone Adapter and SIP is an industry standard for Internet Protocols. ATA/SIP trunks allow the subscriber’s telephone to connect directly to a hosted VoIP service using their own existing internet connection instead of having to configure a new phone system. There are drawbacks to this approach, however.
- Most VoIP providers do not offer dedicated ATA/SIP lines for customers who wish to make calls using VoIP.
- Instead, most providers simply make calls from their normal analog phones to regular phone numbers.
- This makes VoIP phones inconvenient – particularly if you need to make international calls.
- Most VoIP providers also charge much higher rates for long-distance calls than they do for local calls.
- To make things worse, ATA/SIP lines are rarely available from high-speed internet connections.