VoIP Virtual PBXs

Voice over IP stands for Voice over Internet Protocol. In conventional telephony (PSTN), calls travel over physical copper telephone lines. VoIP, on the other hand, converts the sound of a conversation into digital signals and transmits them over the Internet in the form of data packets. By using packet-switched technology instead of telephone circuits, VoIP makes efficient use of the network: multiple conversations can flow over the same shared data connection.

To use this technology requires a VoIP service or application, broadband Internet access, and usually a SIP trunk provided by a VoIP operator to interconnect with the traditional telephone network when calling fixed or mobile numbers.

A virtual PBX (IP PBX in the cloud) is the logical evolution of PBXs: it works as a cloud service provided by an operator, hosted in the provider's redundant data centers, so that the user company only needs a good Internet connection to use it.

Operation process of a VOIP virtual PBX:

• To make calls, the user can use a physical IP phone, an application installed on his computer or cell phone and webRTC (access to the platform via browser).
• The user has credentials and an internal extension within the system. The extension could be configured on as many devices as desired. For example, the same internal number could ring at the same time on the office phone and on the employee's cell phone.
• The user logs on to the platform, leaving his terminal connected to the service.
• When a call is originated, the virtual PBX uses Session Initiation Protocol (SIP) to route it to the appropriate recipient: if it is an internal extension of the same company, it connects both users directly via the Internet; if it is an external number in the public network, then it sends the call through the VoIP provider to the PSTN.
• From the perspective of the external user calling the company, it makes no difference: the company will have one or more public telephone numbers (DIDs) associated with its virtual PBX, so that external customers or contacts will dial those numbers and the incoming call will be handled by the VoIP platform in the cloud. It is even possible to port the company's traditional phone numbers to the VoIP platform, making the migration transparent to callers.

The virtual PBX handles all call management protocols centrally. This includes sophisticated functions that are difficult to achieve in classic PBXs: time-based routing rules, personalized greeting locutions, call jump groups, interactive voice response (IVR) systems and automatic call distribution (ACD) to manage waiting queues.

• Multiplatform versatility and ubiquity: Allows transmission to smartphones, computers, tablets and IP phones in a cost-effective way. Users are not tied to a fixed phone in an office, enabling teleworking and geographically distributed operations. In addition, more than one simultaneous call can be handled over the same data connection, making it easy to scale communications without adding additional physical lines.

• Scalability and ease of adding lines: it is easy to reduce or increase the number of extensions or lines available by simply configuring software, without installing new cabling. It becomes a configuration task in the virtual PBX, with very low marginal costs compared to expanding a traditional PBX. In fact, VoIP has already been widely adopted, and in many industries it is already the dominant form of telephony, replacing conventional fixed lines.

• Built-in advanced functionality: many features that used to cost extra are now included or easy to implement with VoIP. For example, call forwarding, Caller ID, voicemail, automatic redialing and even call recording and intelligent forwarding. It also facilitates unified communications, integrating video conferencing, instant messaging and real-time collaboration.

• Cost savings and infrastructure reduction: no extensive dedicated infrastructure is required: the system can be installed quickly and grow on demand. For example, with mobile applications and web clients(softphones), it is not even necessary to purchase expensive desk phones for each employee, which reduces the initial investment for SMEs. Long-distance calls are often much cheaper or even free within the corporate network, and rates to external phones are lower than with conventional telephony.

• Call quality and performance: with a high-capacity Internet connection, they provide better voice quality with very low latency. Voice over IP protocols are optimized for real time, so that the user experience (dial, talk, hang up) is almost the same as that of a classic telephone, provided there is adequate bandwidth and traffic prioritization (e.g. through QoS in the local network).