VoIP refers to the transmission of voice communication over the internet instead of a regular landline. VOIP systems depend on the underlying architecture and others’ complexity and performance 

Components of VoIP:

  1. Session Border Controller (SBC): Connects to analog call services with digital voice calls, and call records, and provides bandwidth management control. Also, they regulate the flow and balancing of network traffic to maintain superior performance. Behind this VoIP gateway is access to the Public Switched Telephone Network (PSTN).
  2. Media server: Enables features like voicemail and video calling, as well as voice-to-email, interactive voice response (IVR), and voice-based dialing. These provide useful functions like call recording, call queue messages, and more. These media gateways can handle hundreds, even thousands, of SIP calls at once.
  3. Application server: Enables call forwarding, call waiting, call transfer, phone service to the IP network, and call detail records. These are essential to provide users with core telephony features.
  4. Database services: Stores the registration details for all SIP devices, which locates an endpoint and translates addresses that are potentially different in various networks. These maintain call logs for all internet telephony activities.
  5. SIP services: Session Initiation Protocol (SIP) takes care of connecting, disconnecting, and setting the parameters of call sessions. It acts as the foundation for modern voice, messaging, and video technologies.
  6. IP PBX: An Internet Protocol (IP)-ready Private Branch Exchange (PBX) use to provide telephony within a company. It acts as the main control center for legacy phone systems. These rely on SIP trunking for voice service.
  7. Endpoint devices: These are the VoIP phones or softphones (including smartphone apps) that receive VoIP phone service. Examples include desk phones, VoIP apps, conference phones, and even fax machines.
  8. IP network: This allows the voice data packets to travel between endpoints over an Internet Protocol network to upstream services accessible via one or more IP addresses.
  9. Codecs: Codec stands for ‘coder-decoder’.  For optimal call quality, codecs convert analog signals to digital packets with different types of compression. G.722 is the standard for HD voice calls.

There are four types of VOIP networks:

  1. Business Phone Service: this type of VoIP network is so popular. Each desk phone connects to your network switch then the phones sync with the VoIP provider to download its configuration automatically. Users can extend this with smartphones. They can also manage features like voicemail, call forwarding, team messaging, etc.
  2.  SIP Trunking: Session Initiation Protocol (SIP) is an application layer control protocol for establishing, maintaining, and terminating calls between two or more people. SIP architecture includes clients and servers.
  3. First-generation: VoIP solutions were built after the traditional phone systems. They offer services that are fully compatible with PSTN concepts.
    Second-generation: VoIP solutions provide communication services over a closed network. Users have to be registered to access the service, and the traffic is free. Skype is a good example of such a product.
    Third-generation: VoIP allows various combinations of third-party hardware and software. It’s also referred to as a ‘federated VoIP’ system because it relies on dynamic connectivity between internet domains. An example of such a product is Google Talk.
  4. Call centers:  It complements additional functionality including call queueing, live monitoring, and dynamic call routing on business phone service. It also provides fine-grained controls over hours handling, agent priority, holidays, scheduling, and analytics.