From ARPANET(Advanced Reseracha nd Prjects Agency Network) in 1973 by US dept of defence , invention of HTTP in 19196 and finally evoluation of SIP in 2000 and availiability of broadband ethernet services, the telecom landscape has evolved.
As far as infrastructure, services, and contents are concerned, the VoIP industry is witnessing a migration from POTS / PSTN/ Legacy integrations to NGN (Next Generation Network).
NGN is being implemented globally as a means to change the cost base, agility and service capabilities of telecoms providers. The evolved architecture for the transition is one that provides flexibility to service providers by enabling them to deploy new services on IP based technologies, while leveraging existing services and infrastructure as long as it makes sense.
This post describes the evolution of voice communication in access , transport and session layers respectively.
Read more about IMS ( Ip multimedia System ) IP Multimedia Subsystem ( IMS )
It is noteworthy that SKYPE provided VoIP services ( since 2003) much before mobile phone had 2G/3G ( 2010). In current times with many fantastic options to choose from( whatapp , FB messenger , insta cht , Viber , Hangouts ..) given the high bandwidth with 4G/5G and mych advanced media / signal processing tech , the glocal voip scene is touching 400 mililion subscribers and looks very attractive with 1.5$ billion market .
Enterprise communication systems
On premise private branch exchanges ( PBX ) were the first kind of business telephone systems to which the analog PSTN systems of the company were conneced. These analog circuits were then replaced by digital PBX which provided enhanced features liek screening , voicemails , shared lines.
In the current landscape , the digital PBX of the company is connected to the external telco privider via a SBC or SIP trunking service .
An ompremise LAN based voIP system can be accessed from outside via a VPN on SSL/ IPsec. Although it incures greater CAPEX but ensufe maximum control and ownership of the data . Many time the local laws mandate the server to be hosted with a partuclat geographical area too where an on premise setup and data centre is used.
Enterprise communication shifts from on-premise to SaaS (cloud)
As for remote worksforce and employees working from home (such as during lockdown , pandemics ) it is even more crticial for enterprises to maange inter communication between teams and keep the communication private ie not using piblic messaging platforms , hence the role of cloud based PBX integrated with secure and end to end encrypted telco providers is of prime importance .
To read how a SME can setup their own flexible and scable enterprise comunication system read –
VoIP/ OTT / Telecom Solution startup’s strategy for Building a scalable flexible SIP platform https://telecom.altanai.com/2013/11/21/what-should-a-telecom-solution-startup-do/
With the advent of other disruptive technologies such as free and opensource codecs in browser with WebRTC and well defined framework and standards , voIP definetly looks detsined to expand by leaps and bounds.