Voice Over IP (VoIP): The Future of Phone Calls Explained

VoIP transmits sounds, voices, and multimedia content over IP. VoIP is an acronym for Voice over Internet Protocol.

The Internet is an example of an Internet Protocol network. VoIP is also called IP telephony(Internet Protocol telephony).

The terms broadband telephony, broadband phone service, and Internet telephony refer to providing communications services over the public Internet.

These services include voice, fax, SMS, and voice messaging. They are provided over the public Internet rather than via the PSTN (public switched telephone network).

The PSTN is also known as POTS (plain old telephone service). 

Overview

The principles and steps in originating VoIP (Voice over Internet Protocol) telephone calls are similar to traditional digital telephony.

The principles and steps involve channel setup, signaling, encoding, and digitizing analog voice signals.

Digital information is packetized, and transmission occurs as IP packets over a packet-switched network instead of a circuit-switched network.

They convey media streams using special media delivery protocols that encode video and audio with video and audio codecs.

Several codecs optimize the media stream based on network bandwidth and application requirements.

Some implementations rely on compressed and narrowband speech, while others support high-fidelity stereo codecs.

VoIP’s most popular speech coding standards are based on the modified discrete cosine transform (MDCT) and linear predictive coding (LPC) compression methods.

Popular codecs include the LPC/MDCT-based Opus (used in WhatsApp), the MDCT-based AAC-LD (used in FaceTime), A-law and μ-law versions of G.722 and G.711, and the LPC-based SILK (used in Skype).

Early providers of VoIP services use business models. They also offered technical solutions that depict the architecture of the legacy telephone network.

Second-generation providers built closed networks for private user bases, offering convenience while certainly charging for access to other communication networks.

An example of this communication network is the Public Switched Telephone Network (PSTN).

Third-generation providers, such as Google Talk, adopted the concept of federated VoIP(Voice over Internet Protocol).

These solutions mostly allow dynamic interconnection between users in any two Internet domains when a user wishes to place a call.

Furthermore, VoIP is also available on many PCs (personal computers) and other Internet access devices.

SMS text messages and Calls may be sent via the carrier’s mobile data network or Wi-Fi.

VoIP (Voice over Internet Protocol) provides a structure for consolidating all modern communications technologies using a single unified communications system.

Protocols

VoIP has been executed with proprietary protocols and protocols based on open standards in applications such as web-based communications, VoIP phones, and mobile applications.

The following are the protocols of VoIP:

• The Session Initiation Protocol (SIP) is a connection management protocol developed by the IETF (Internet Engineering Task Force).
• H.323 is one of the first Voice over IP call control and signaling protocols to find widespread implementation. However, since the spread of newer, less complex protocols such as SIP and MGCP, H. 323 deployments have become increasingly limited to carrying existing long-haul network traffic.
• Media Gateway Control Protocol (MGCP) also manages connections for media gateways.
• Gateway Control Protocol (H.248, Megaco) is a control protocol for media gateways across a converged internet network consisting of modern packet networks and traditional PSTN.
• Real-time Transport Protocol (RTP) is a transport protocol for video data and real-time audio.
• Real-time Transport Control Protocol (RTCP), a sister protocol to RTP(Real-time Transport Protocol), provides status information and stream statistics.

Various functions are needed to execute VoIP (Voice over Internet Protocol) communication. Some protocols perform a few functions, while others perform multiple and must be used in concert.

These functions include:

• Session management involves managing and creating a session, which is a connection between two or more peers that provides circumstances for further communication.
• Network and transport—Creating genuine transmission over ungenuine protocols may involve accepting data receipt and retransmitting data that wasn’t received.
• Signaling involves performing registration (such as advertising one’s presence and contact information) and discovery (such as locating someone and obtaining their contact information). Signaling also involves dialing (including reporting call progress), negotiating capabilities, and forwarding/transfer. Also, it consists of making call control (such as muting, holding, and dialing DTMF keys during a call [for example, to communicate with an automated attendant or IVR], etc.).
• Media description: This means determining what type of media to send (video, audio, etc.), how to decode/encode it, and how to receive/send it (ports, IP addresses, etc.).
• Quality of service refers to providing feedback or out-of-band content about the media, such as statistics, synchronization, etc.
• Media: These functions mean transferring the actual media in the call, such as video, audio, files, text messages, etc.
• Security: Security involves verifying the identity of other participants (people or computers) and implementing access control. Furthermore, it includes encrypting data to control messages or protect the integrity and privacy of the media contents.
• Secure Real-time Transport Protocol (SRTP) is also a VoIP protocol. It is the encrypted version of RTP(Real-time Transport Protocol).
• Session Description Protocol (SDP) is a syntax for session initiation and announcement for WebSocket transports and multimedia communications.
• Inter-Asterisk eXchange (IAX) is the protocol used between Asterisk PBX instances.
• VoIP protocols also include the Extensible Messaging and Presence Protocol (XMPP), Presence information, Instant messaging, and contact list maintenance.
• The jingle is for peer-to-peer session control in XMPP.
• Skype protocol, a proprietary Internet telephony protocol suite based on a peer-to-peer architecture

Benefits of Switching to VoIP

Voice over IP offers several financial benefits compared to a local telephone company’s service.

When comparing VoIP to a local telephone service, three unique features stand out for companies with call centers, growing long-distance bills, or a large office workforce.

They include:

• Increased productivity: Voice over IP increases worker productivity by integrating voice calls with unified cloud collaboration platforms, communications, and business intelligence applications.
• Reduced phone charges: VoIP uses the Internet to conduct voice calls. As a result, VoIP can establish connections anywhere in the world without incurring long-distance charges. On the other hand, traditional phone service would charge high for calls placed to different landlines. One of the merits of VoIP is that calls made within the same service provider’s network are free, no matter the distance between the calls. Calling costs are much lower than traditional phone services for calls placed to different landlines or networks.
• Better scalability: Traditional phone systems must be installed on-site to function and support a certain number of users at a location. Voice over IP can be scaled up as a business grows faster at less cost.
• Connect multiple offices: Businesses that want to span numerous locations across one or more countries can find traditional phone service a logistical headache. Connecting numerous offices is an important area where VoIP is really useful. Voice over IP allows businesses to combine the phone systems of multiple offices of an organization into one system.
• Save on outmoded phone systems: Traditional landline phone service requires expensive on-site equipment maintenance. We also always need equipment upgrades to increase the number of available lines. VoIP (Voice over Internet Protocol) eliminates this maintenance because it uses the location’s existing local area network.
• Broadband Internet service: Most organizations have the bandwidth and internet infrastructure to switch to VoIP( Voice over Internet Protocol). Most call centers might require increased bandwidth for a location, but voice-over IP usually doesn’t require major upgrades.
• Overcoming geography: International organizations face the unique challenge of merging teams spanning two or more countries. Voice over IP can make bridging the geographical divide much easier when included in a larger technology package for managing remote teams.
• Managed VoIP services: Managed service packages like Epik offer all the software and hardware needed as a complete service package for a simple per-user monthly charge. Offers like these take out the headache of switching to VoIP for businesses that want to avoid the expense of purchasing and owning VoIP hardware.

Disadvantages of Using VoIP

The disadvantages of replacing a traditional phone system with VoIP relate to its dependency on internet technology to deliver voice calls.

Besides, the most common cause of VoIP quality issues is bandwidth limitations and the Internet.

Whether it is the difficulties that an unreliable internet connection can create or the increased electricity cost, VoIP has a few drawbacks.

The following are some possible drawbacks to be aware of when choosing a VoIP service.

• Need for a power source: Traditional telephones are powered with electricity supplied through a landline, which means they can function during local power outages. The electricity supplied by landline is delivered by the local telephone company. On the other hand, VoIP devices use power from a wall socket, which means they can fail during local power outages unless emergency power is available. An organization’s need to supply power can increase its utility bill.
• Call quality: Quality issues can happen with VoIP, such as excessive delays or noise when placing calls on the line, which we usually don’t encounter with landlines. When these issues come up, they can be difficult to track down because they may be caused by insufficient bandwidth, poor internet service, or the VoIP service provider. The VoIP hardware might even cause the problem.
• Security: Another disadvantage of VoIP technologies is the boundless security risk of sending data over a public network. Many Hosted systems and VoIP phones are designed to encipher the voice data they send over the Internet to protect against harmful eavesdropping. Nevertheless, organizations concerned about the potential loss of privacy should examine security closely when considering a VoIP service.
• Consumes internet bandwidth: VoIP will add a bandwidth load to your existing internet service because it operates over a broadband connection. Large organizations may need to increase their bandwidth to accommodate the data usage that a new VoIP service will require. Many Voice-over IP providers like Epik offer unlimited bandwidth with fiber optic internet plans to solve this problem.
• 911 emergency calling: Another disadvantage of VoIP is that it doesn’t provide for 911 emergency calls. Regulators have not required voice-over IP to offer a connection to 911 service.

Getting the Best VoIP Experience

There are various ways an organization can get the most out of VoIP. Here are a few ideas to optimize the benefits of VoIP:

• Responsive support: An important aspect of VoIP service that we can benefit from is the responsiveness of the customer support offered by the service provider. Look for providers who guarantee resolution and response times and provide multiple contact channels like phone, social media messaging, and online chat.
• Up-time guarantees: An uptime guarantee is important when choosing a managed or hosted internet service. With the birth of cloud technologies, some service providers have pushed these guarantees as high as 99.8%. The guarantees were pushed high because they could restore service with backup servers and quickly respond to outages. We should choose a service provider that stands by its guarantee.
• Hosted Voice over IP (VoIP) solutions: Modern hosted solutions use cloud servers to provide the connectivity needed to manage a site’s VoIP service. Replacing the resources needed for the required number of users is a simple process of changing server settings or subtracting or adding cloud servers. This also makes recovery from hardware failures reliable and fast.
• Fibre optic internet service: Fibre optic internet services like Epik’s FIBERLINK allow organizations to operate their private network that connects disparate locations to the Internet. The service provider manages and maintains these dedicated network connections 24/7. The reliability and bandwidth of a private fiber-optic network are much higher than standard broadband internet connections. A private fiber-optic network allows our VoIP data to travel securely unobstructed, avoiding public internet traffic.