Last time, we discussed the fundamentals of VoIP, including its advantages, the basic terms used in VoIP, and the VoIP Protocols. What are the Components of VoIP?
The timing is right to introduce each of the parts that go into Voice over IP. They are essential to the existence of IP telephony as we know it today.
In this essay, I’ll mostly concentrate on explaining the key VoIP components and outlining each one’s key features.
Each VoIP component has a distinct specification provided by various standards. Accordingly, I’ll limit myself to the most crucial ideas that are universally acknowledged and accepted in order to keep things simple. I anticipate that after finishing this article, you will understand how VoIP is put together.
Components of VoIP
The following are the top four VoIP components:
- Controlling Gateway for signals
- Media Portal
- Server for media
- Serving applications
Controlling Gateway for signals
The Signaling Gateway Controller (SGC), as you may recall from my VoIP Essentials article, refers to as a “called agent” due to its call control role and is also frequently dub a “Media Gateway Controller” due to its Media Gateway control function.
The SGC entity performs a number of roles. It is the core of the VoIP platform and serves as the link between the IP and PSTN (public switched telephone network) worlds.
SGC component’s primary attributes
- Support for the Signaling System 7 (SS7) protocol stack, the primary signaling protocol suite used by the PSTN worldwide (sometimes a separate entity called Signaling Gateway is used for this exact purpose).
- Full support for IP-only signaling protocols like SIP and H.323, which used to control voice calls.
- Complete support for media control protocols used to manage Media Gateway session connections and parameters, such as MGCP or Megaco (H.248).
- For invoicing purposes, create call detailed records (CDRs).
- Provide admission control techniques for bandwidth management; in other words, new sessions only permit provides the system has the bandwidth to provide them with satisfactory service.
- Support for bandwidth policing techniques – The Signaling Gateway Controller orders the Media Gateway to monitor the RTP media flow and apply rate limit policies to aggressive flows. Also, This is done through the use of media flow profiles. Additionally, this approach maintains acceptable Quality of Service levels.
- Provisioning a media connection entails assigning particular DS0 allocations for the reservation of media resources to Media Gateways, along with connection features like coding and packetization.
As you can see, the SGC must be redundant because it is the most crucial part of the entire VoIP structure. Additionally, Failure of this component due to hardware or software is not acceptable. Additionally, because of the way it handles several tasks and processes, it needs a powerful CPU and RAM.
Media Portal
Transmission of voice packets utilizing the RTP transmission protocol is the Media Gateway’s primary function. Since the media gateway employs TDM trunks on one side and IP trunks on the other when it utilizes a converged PSTN/IP network, it has additional tasks to do, such as packetization.
Let’s look at the primary duties of the Media Gateway:
- Support for the Media Gateway Controller’s (MGCP) or Megaco’s (MEGACO) call control system.
- When TDM trunks are interacting with the Media Gateway, RTP packetization of data is also used for voice data transmission.
- T1/E1 trunk support for audio transmission in SS7 networks
- Support for various compression algorithms to meet the call’s needs as directed by the SGC.
- Control DSP (Digital Signal Processing) resources for the best service provision.
Maintaining redundant IP links might also help achieve some level of high availability. Consequently, The capacity of the onboard DSPs and the choice of codecs, as different codecs have varied processing needs, are the two key determinants of the Media Gateway’s concurrent call support capabilities.
Server for media
When other functions require, such as voicemail or video conferencing, a media server employ. Accordingly, A media server also utilize when special announcements or tones need to be broadcast. As a result, the media server plays a crucial part in VoIP design.
The Media Server’s primary duties are:
- transmission of special service announcements and call progress tones
- voicemail capability
- automatic voice dialing
- Transmission of voicemail through email — Voicemail can be sent as an attachment to an email address
Serving applications
The primary duty of an application server is to offer the IP network value-added services. Here, services that are both global and customer-specific provide. Although, The application server has an impact on call parameters and session rules.
The Application Server component’s primary duties are:
- support for private dialing plans that are customizable
- Basic service provision — Through the Application Server, basic services including call forwarding always, call forwarding on busy, call waiting, call transfer, call park, and voicemail are made available.
- Advanced service provision — This component may provide advanced features including phone authorisation using a PIN, remote office, and “follow me” programs.
- Creation of Detailed Call Records (CDRs)
FreePhone Service—support for 800 number services that charge the person phoned.
The VoIP architecture’s brain is the Application Server. Basically, With the Signaling Gateway Controller, it communicates using protocols like SIP or H.323. Comparatively, Here, services are put into action and distribute to clients.
High availability configuration is crucial; any type of service interruption must avoid.
Upcoming VoIP Information
I made an effort to combine the most crucial features of each VoIP call component and give them to you in the most straightforward manner. Afterward, I hope this information was helpful to you.
