Voice over Internet Protocol (VoIP) is a general term for a family of technologies to deliver voice communications over IP networks (like the Internet). Terms synonymous with VoIP include IP telephony, Internet telephony, SIP, Skype, voice over broadband (VoBB), broadband telephony, and broadband phone.

VoIP systems use protocols to control the set-up and tear-down of calls as well as audio codecs which encode speech over an IP network (and often a range of codecs are used). Routing VoIP phone calls over data networks (to avoid the need for separate voice and data networks) can reduce communication and infrastructure costs.

Over the last decade, a variety of business-drivers have created a need for businesses to impliment VoIP into their organisation in one way or another. VoIP can facilitate tasks and provide services impossible using traditional methods. You can transmit more than one telephone call over the same broadband connection can reduce costs. Secure calls can be made using standardized protocols (such as Secure Real-time Transport Protocol.) Location independence and mobility can be easily achieved using a varety of business VoIP-related solutions – with only a non-business grade Internet connection is needed to get a connection to a VoIP provider. For instance, call center agents using VoIP phones can work from anywhere with a sufficiently fast and stable Internet connection. Integration with other systems and services including video conversation, message or data file exchange in parallel with the conversation, audio Business Conferencing, managing address books, and passing information about whether others (e.g., friends or business colleagues) are available to interested parties.

Because an IP network is unreliable (in contrast to the circuit-switched public telephone network) and does not inherently provide a mechanism to ensure that data packets are delivered in sequential order, VoIP implementations face problems mitigating latency and jitter.

Voice travels over IP networks in packets in the same manner as data, so when you talk over an IP network your conversation is broken up into small packets. These voice and data packets travel over the same network with a fixed bandwidth. This system is more prone to congestion and DoS attacks than traditional circuit switched systems.

Some delays can be minimized by marking voice packets as being delay-sensitive.

A cause of packet loss and delay is congestion, which can avoided by means of QoS. The receiving end must restructure IP packets that may be out of order, delayed or missing, while ensuring that the audio stream maintains a proper time consistency. Variation in delay is called jitter. The effects of jitter can be mitigated by storing voice packets in a jitter buffer upon arrival and before producing analog audio, although this further increases delay.

When IP packets are lost or delayed at any point in the network between VoIP users there will be a momentary dropout of voice if all packet delay and loss mechanisms cannot compensate. It has been suggested to rely on the packetized nature of media in VoIP communications and transmit the stream of packets from the source phone to the destination phone simultaneously across different routes.

A number of protocols have been defined to support the reporting of QoS/QoE for VoIP calls. These include RTCP XR (RFC3611), SIP RTCP Summary Reports, H.460.9 Annex B (for H.323), H.248.30 and MGCP extensions.

A phone or telephone system encompasses the general use of equipment to provide voice communication over distances, specifically by connecting telephonesto each other. A telephone system may also be known traditionally as a PBX (Private Branch Exchange) or PABX.

Many people’s experience of a telephone system is a strange box on the wall, or a fridge-sized box in the server room, which remains on, but nobody knows how to administer it. Times are changing however, and most modern systems are small units, aesthetically lookling like a small network appliance, or a 19″ rackmounted unit, more akin to a computer server.

IP Telephony is a modern form of telephony which uses the TCP/IP protocol popularized by the internet to transmit digitized voice data. Contrast this with the operation of POTS (an acronym for “Plain Old Telephone Service”).

IP Telephony has a wide range of advantages over the ‘old school’ telephone systems. It is much more closely aligned with the data network, which virtually any modern business or organisation already has in place. It uses the same network equipment, the same physical infrastructure, and will scale to the size of the ‘network’ accessible to it (once this includes the ‘internet’, the possiblities are endless).

IP Telephony has been proposition for nearly two decades now, but is gaining traction year on year. Whereas 5 years ago an IP phone or IP line between telephone systems was an interesting addition, it is now part of the de-facto standard system.

An IP phone uses Voice over IP (VoIP) technologies allowing telephone calls to be made over an IP network such as the internet instead of the ordinary PSTN system. Calls can traverse the Internet, or a private IP Network such as that of a company.

IP phones use control protocols such as Session Initiation Protocol, Skinny Client Control Protocol or one of various proprietary protocols such as that used by Skype.

IP phones can be simple software-based Softphones or purpose-built hardware devices that appear much like an ordinary telephone or a cordless phone.

There also exist the possibility to reuse ordinary PSTN phones as IP phones, with analog telephony adapters (ATA). It may have many features an analog phone doesn’t support, such as e-mail-like IDs for contacts that may be easier to remember than names or phone numbers.

Contact Centres for Businesses within the 21st Century incorporate technologies such as speech recognition systems and speech synthesis software to allow computers to handle first level of customer support, text mining and natural language processing to allow better customer handling, agent training by automatic mining of best practices from past business or interactions, and many other systems and technologies to improve agent productivity and customer satisfaction.

Automatic business leads selection or lead stearing is also intended to improve business efficiencies, both for inbound and outbound campaigns, whereby inbound calls are intended to quickly land with the appropriate agent to handle the task, whilst minimising wait times and long lists of irrelevant options for people calling in, as well as for outbound calls, where lead selection allows management to designate what type of leads go to which agent based on factors including skill, socio-economic factors and past performance and percentage likelihood of closing a sale per lead. The concept of the Universal Queue standardises the processing of communications across multiple technologies such as fax, phone, and email.

A Unified Contact Center provides your agents with a smart multimedia solution that can cope efficiently with large numbers of inbound inquiries and outbound contacts – by email, fax, IM, web chat, SMS or phone. Agents can deliver a superior performance that has a positive impact on customer satisfaction, your callers’ brand experience and revenues.

The right solution lets you improve contact center management. Reports help to finetune performance. More importantly though, you can empower your agents by introducing real-time self-monitoring functionality with Agent Desktop – so they can better self manage their workloads.

An IP PBX handles voice signals under Internet protocol, bringing business benefits for computer telephony integration (CTI). An IP-PBX can exist as physical hardware, or can carry out it functions virtually, performing the call-routing activities of the traditional business telephone system , in the form of PBX or key system as a software system. The virtual version is also called a “Soft PBX”.

Unified Messaging (or UM) is the integration of different streams of communication (e-mail, SMS, Fax, voice, video, etc.)enabling businesses to bring all of these mediums into a single unified message store, accessible from a variety of different devices.

Unified messaging is a subset of a fully integrated business Unified communications system. While traditional business telephone systems delivered messages into several different types of stores—voicemail systems, e-mail servers, and stand-alone fax machines—with Unified Messaging all types of messages are stored in one unified system. Voicemail messages, for example, are delivered directly into your inbox. You see them right beside your e-mail when you open up Outlook, offering powerful new ways to collaborate more effectively. For example, you can forward a voicemail or fax. You can even take notes in your voicemail message or search for old voicemail messages. No more notes stuck to your monitor!

Today, UM solutions are increasingly accepted in the corporate business environment. The aim of deploying UM solutions generally is to enhance and improve business processes as well as services. UM solutions targeting professional end-user customers integrate communications processes into the existing IT infrastructure, i. e. into CRM, ERP and mail systems (e. g. Phoenixnet PH, Microsoft Exchange, Lotus Notes, SAP, etc.).