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What is SIP Calling and How Does It Impact Business Growth?

what is sip calling

Communication is the main pillar of any business that aims to grow and expand. So, if you are a business owner, you should consider having a SIP calling system. SIP is the modern alternative of the traditional phone system; it operates through the internet granting you better call quality, and saves you lots of money.

What is SIP Calling? 

SIP calling, known as Session Initiation Protocol, is the process of modern office  phone system that transfers voice and video calls over the internet. Sip calling  processes take place through sip trunk, which is the virtual form of a phone line. Sip  calling is meant to eliminate the hassle of the traditional office phone system with all  its cons. This article will take you through a must-have modern solution for your  business, and answer all your inquiries about it. 

How Does a SIP Call Work? 

There are many differences between the SIP calling system and the traditional phone  system in terms of working processes that will make you choose SIP calling, get to know these differences below!

So, traditional systems consist of the following: 

It has been decades since people started using this traditional system, and it does not cope now with the modern changes in the business world because this system is not flexible to use anywhere, costs lots of money especially when it comes to repair, and its call quality is not controllable. 

On the other hand, SIP calling works as follows: 

  • It eliminates the usage of PRI lines 
  • SIP calling starts through SIP trunk that is virtually installed over the  company’s internet connection 
  • SIP trunk then connects PBX to PSTN through the cloud

As a result, with SIP, you can: 

  • Make conference calls, video chatting, voicemail, and exchange documents
  • Use any preferred device to make the calls 
  • Exchange multimedia files 
  • Have inbound and outbound calls regardless of the location 

So, if you use different platforms to manage the above services and more, SIP is  there to allow you manage them all through one system. 

Benefits of SIP Calling 

If you want to know why you should have SIP trunk as soon as possible, check the  following benefits! 

Expand without limits 

Whether you are hiring more employees or willing to expand in new locations,  you don’t have to buy more physical lines or change the phone system. SIP trunk  will allow you to get your different locations interconnected through one phone  system. Also, the unlimited channels of SIP trunk will keep your communication  efficient and quickly regardless of the number of calls or employees.

Save costs drastically 

As long as SIP calls rely on the internet to grant you a virtual connection, it saves  costs in terms of eliminating: 

  • Getting charged per minute, but unlimited calls will be granted with SIP  through a fixed monthly fee 
  • Subscription fees for various services, but all services through SIP will be in  one system with a unified fee 
  • Extra charges of international calls, but all calls through SIP are dealt with  as local calls 
  • High maintenance costs of traditional system that keep rising because it is  becoming outdated 

So, you will pay much less money when you have SIP trunk, and you will get ideal  quality compared to traditional phone system represented in PRI. 

Unified communications 

SIP phone system allows you to synchronize all your communication channels. As  a result, SIP system will: 

  • Grant you a unified virtual communication system 
  • Ease the communication among employees regardless of their number
  • Let your team make voice or video calls, exchange files and send instant  messages 
  • Make your employees become reachable wherever they are through their  smartphones 
  • Allow employees to show their working hours through marking themselves  as online or offline  
  • Transfer calls automatically to the available yet relevant employees Poor-quality is never an option 

Poor-quality is never an option

While traditional landlines may fail you, SIP phone system will never do. 

Some unexpected scenarios may cause the traditional phone system to go down.  So, this may cause business disruption or revenue loss. On the other hand, SIP  system has a built-in redundancy that extremely diminishes any chance of failure. However, if any outage happened, the SIP service provider reroutes the calls to  other locations or mobile phones to provide you with the same quality. Thus, your  business communications maintain their reliability and high-quality. 

Easily absorbed system 

SIP Phone system is characterized with: 

  • A simple interface that improves user experience 
  • Smooth steps that allow employees to master using it 
  • Easy maintenance procedures through the online control panel 

SIP service provider is responsible of implementing it in your office, training your  employees on using such a system and making sure that they all are mastering it  well.  

SIP Calling Requirements 

SIP calling operates through a systematic internet process to start and end SIP  calls as you wish. These are the technologies that are implemented within our SIP  system to make connections happen.  

SIP Addresses 

SIP calling allows connections to happen from one location to the other, and in  order for this to happen, there has to be a SIP address. SIP address functions as  the destination to which messages and calls are directed to. You can link a SIP  address to a certain individual or even a computer application, and proceed  starting and receiving calls and messages. Further, during a SIP session, the system notifies you if someone joins or leaves the sessions. At the end of SIP calls,  you can easily cut off the connection with the address.  

SIP Codecs 

In order for voice signals to be transmitted and sent through SIP phone system,  there should be “codecs.” Codecs is an abbreviation for “coder decoder” that its  main mission is to get the digital from of the analog voice signal so it becomes  easier to transmit it. Codecs types are many but the most used types in the  market are G.711 and G.729 

The difference between them is that: 

  • G.711 provides a high quality of voice, but it requires much of bandwidth  consumption in order to provide such quality 
  • G.729 diminishes the voice quality a bit, but it is a better option in areas  where bandwidth is not available that much 

SIP Protocols 

Did you know what follows the encoding of the files we just talked about? 

There are two protocols that get the mission done. If you could imagine that the  internet is the things connects the sender and the receiver, you may be a bit  wrong. There should a helper that takes what the sender wants to send and  delivers it to the internet, and this is “RTP” or Real-Time Protocol so it mainly  transfers things through the network. On the other hand, “RTCP” or Real-Time Transport Control Protocol is mainly responsible of maintaining the best quality of  delivery of the things carried by the RTP. 

SIP Phone System vs. Other Communication Systems

In order to settle on a decision, you need to go through the compare and contrast process. That is why ULTATEL brought to you this comparison between SIP and other well-known systems. 

SIP vs. ISDN  

ISDN Calling, known as Integrated Services Digital Network, is a phone system  that provides more advantages compared to the traditional PSTN. So, it transmits  voice and data over digital copper lines. In contrast with SIP trunk, ISDN grants  only 64kbps rate when it comes to data transfer whereas SIP does not really have  a limit as long as the connection allows the speed. Also, ISDN will make you pay  for both voice and data on a separate basis because it has several service points.  Moreover, ISDN will not help you scale up your business as SIP will do because it  is limited to 23 branches per trunk.  


VOIP is known as Voice Over Internet Protocol, and SIP complements many of the  services you can get from VOIP. In many cases, you should have SIP and  VOIP in your premises. SIP facilitates VOIP calls to let the communication become  faster and more efficient. If your communication does really require anything  more than voice, VOIP will be enough. However, when it comes to multimedia  communication, SIP is a must for VOIP to function.  

Frequently Asked Questions 

There is more to know about SIP calling, so you have a full background that helps you decide whether you need it or not. So, you will find the most asked questions by our clients answered below.

Can I make SIP calls on an iPhone/Android? 

In order to make it easier for you and your staff, SIP allows you all to make calls  through a device you have all the time whether it is iPhone or Android.  

SIP calls on mobile phones will enable you to: 

  • Detach personal calls from business ones 
  • Get the calls even if your device has various numbers 
  • Have high performance calls even if the coverage is limited 

Both iPhone and Android will allow you to receive SIP calls through very easy  steps in the settings that your SIP provider who is ULTATEL will help you with.

Who uses SIP calling? 

It doesn’t really matter whether you have a small business or an enterprise as  long as you have a PBX system in your premises. We never deny that incorporating  SIP phone systems in small businesses is much easier because the number of  employees, branches and numbers are much less than those of enterprises.  However, the more you postpone having a SIP system in your company, the more it  will cost your company a lot later on. If you are still wondering why you should  have a SIP system, look at the following reasons below! 

  • Makes users reachable easily 
  • Guarantees the best contact with clients worldwide 
  • Helps with managing time and collecting data a lot 
  • Enables working wherever there is a connection with the internet • Connects you with anyone, anywhere and at any circumstances 


As David Chappelle once said “Modern problems require modern solutions,”  which is the exact thing that SIP trunk offers to the world of communication. Businesses in our modern world pretty much depend on communication, and  unfortunately, telecommunications have been showing a great incompetence in  fulfilling corporations’ needs and wants over the past couple of years. The fact  that basic telecommunication services fail to meet the expectations of the  modern world, the need for an internet-based communication service started to  become more and more pressing, and this is the gap that SIP trunk has been  trying to fill. SIP calling’s main goal is to facilitate communication among members  of small and even big and extended businesses through depending fully and solely  on the internet. It makes communication and collaboration happen in our modern  corporations in an effective, smooth and problems-free way, which provided a  solution to the issues that aroused from depending on outdated and  traditional telecommunication services. Alongside being a smarter and more  effective alternative to our normal and long-used telecommunications, SIP calling is an option that saves money and resources while maintaining a stable and solid  quality of calls, video conferences and meetings. So, if you are looking for a way  to keep your business up to the ever changing and ever developing modern  world, contact ULTATEL and enjoy an experience of futuristic communication that  will one day spread all over the world!

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