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SIP vs VoIP For Business: Everything You Need To Know

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While SIP vs. VoIP is a frequently asked question, they aren’t directly comparable. VoIP refers to the method of making calls over the internet, whereas SIP is a protocol that facilitates those VoIP calls.

Let’s resolve the SIP vs VoIP debate today – the differences, the pros and cons of each and whether you should opt for VoIP or SIP trunking for your business.

What is VoIP?

VoIP or Voice over Internet Protocol is a mode of communication that uses an internet connection to make and receive calls. VoIP networks utilise packet-switching technology to function.

Now, how does a VoIP phone work?

When a call is made from VoIP, the analogue voice signals are converted into digital signals that are sent to the VoIP service provider through the internet. They are then converted into digital packets and transferred to the receiver side. VoIP bypasses the landline company completely.

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What is SIP?

SIP or Session Initiation Protocol is a protocol that manages real-time communication sessions that include video, voice and messaging applications. It is one of the most common protocols used for VoIP.

How does SIP work?

When a user starts a session, a request (or invite message) is sent to an SIP server to locate the recipient. When the recipient is located, it sends a response back to the caller with a status code like 180 Ringing or 200 OK. The caller’s device receives the code and sends an ACK acknowledgement to confirm the establishment of the session.

During the call, SIP can handle changes in the session, for example, adding another participant to a conference call.

SIP vs VoIP: What’s the difference?

SIP and VoIP are not distinctly comparable. VoIP is a communication mode that uses different protocols to manage calls over the internet. SIP is a specific protocol that can be used to manage VoIP calls and multimedia support. In a nutshell, SIP is a subprotocol of VoIP.

VoIP vs Landline for business: Which is the best?

Is it worth switching to VoIP? Read the points below and decide whether VoIP is better for your business or landline.

Pros of VoIP Cons of VoIP
  • Requires no on-site installation like the landline phone system.

  • Low cost.
  • Supports only voice. No multimedia support.

  • Requires a stable internet connection to work.
Pros of VoIP with SIP Cons of VoIP with SIP
  • Supports video, file sharing and other types of media, etc.

  • Easy to integrate with third-party software like CRM.

  • PRI lines can be integrated to create a combination system that allows calls with and without internet.
  • Can incur security issues if set up on a public internet line.

SIP trunking vs VoIP

SIP trunking refers to a combination of SIP channels consolidated into a single connection or “trunk.” These trunks provide VoIP connectivity between an on-premises phone system and public switched telephone network (PSTN). It’s like a virtual phone line that manages voice, video, fax and messaging.

Traditionally, businesses used to rely on physical phone lines to manage calls. SIP trunking shifts that to a cloud-based system where the calls are converted into data packets and transferred through the internet network. Each call that is initiated through an SIP trunk occupies one channel.

SIP trunking offers many benefits including cost savings and scalability. It eliminates the need for traditional phone lines which saves the cost of purchasing copper wires and their installation. Also, it’s more scalable because you can easily adjust the number of lines depending on your needs.

VoIP is enabled by SIP trunking. As such, SIP trunking is a setup method, while VoIP is a communication mode.

SIP phone vs VoIP phone

The major difference between SIP phones and VoIP phones is that you can make voice calls over the internet using a VoIP phone but SIP phones give you multimedia functionality as well. Most of the VoIP phones today are SIP-enabled, though.

SIP vs VoIP for business: Which is better?

SIP vs VoIP for business

A much distinct comparison could be between a VoIP system alone and a VoIP with SIP system.

In that case, if your business can rely on simple voice calls for communication, a VoIP-only phone system is much preferred. But if you require additional multimedia functionality (video conferencing and messaging), VoIP with SIP should be chosen. That being said, you can always integrate your existing VoIP system with SIP protocols.

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Yes, VoIP can function without SIP when your business only needs voice communication support.

PBX refers to the traditional phone system that uses landlines to make inbound and outbound calls. SIP trunking, on the other hand, uses the internet to manage calls. It requires an IP-PBX system to be set up on-site. This PBX can then interface with SIP trunks to connect your existing PBX system to a SIP provider.

SIP phone works by sending a session request to an SIP server which locates the recipient. The recipient responds with a status code, and the caller’s device sends an acknowledgement to confirm the session’s establishment.

Written by:

Isabella Robinson
Isabella Robinson
Isabella Robinson is a seasoned business content writer, leveraging several years of experience to craft impactful narratives that seamlessly blend business insights with engaging storytelling across diverse industries. Her expertise lies in delivering compelling content that resonates with audiences.