What is a SIP trunk? VoIP using the session initiation protocol (SIP)

SIP trunks are a modern telephony connection allowing for calls to be made on the internet using an initiation protocol. This technology is increasingly replacing traditional connections and offers more flexibility.

What is a SIP trunk?

Personal and business calls used to be carried out on landline connections, which has over time proven cumbersome and, in some cases, expensive. Recent technology has made telephoning more modern and flexible. Voice over Internet Protocol (VoIP) telephony is one of the major players in this development. The foundation for this technology is the session initiation protocol (SIP), which allows sessions between two or more people to be initiated and terminated. SIP trunks are responsible for creating the actual connection between individual participants. They connect local telephone systems to the internet and, in some cases, with a cloud server.

The actual job carried out by a SIP trunk is similar to a traditional landline. This modern equivalent can, however, do much more. Instead of using a wired connection which keeps the user set in place, the SIP trunk makes internet services available for telephone calls. This allows people to be more mobile and independent. These services can then be used by multiple devices via a wireless connection. In addition to simple voice transfer, this system is also used for video and other data transfer services. SIP trunks are also responsible for assigning the telephone numbers that are used.

What equipment is needed for SIP trunking?

To use SIP trunking, you need a telephone system. This can be a local system, a cloud-based solution or another virtual system. Regardless of which system you choose, you will need a broadband connection. Once you have these things, you will be able to use SIP trunks. You will then obtain an extension to use for your device, allowing communication to and from it. Depending on the bandwidth you have available, you can connect multiple devices to one account. Each of these end devices will have their own extension. This is particularly useful in an office environment. Access to these individual numbers can be achieved by using the internet protocol.

What are the benefits of SIP trunks?

Switching to a SIP trunk has many benefits. This is the reason why traditional ISDN connections are being replaced in many parts of the world. Some of the benefits of SIP trunking include:

Multiple connections

This is one of the most important features of SIP trunking. With just one SIP trunk, you can use multiple numbers at the same time. They are collated within a number set and all contain their own extension. A central, IP-based telephony system will forward calls to the individual numbers. This makes SIP trunking a strong choice for businesses with a large amount of communication.

More flexibility

SIP trunks are also more flexible than other technologies. If you need a new connection, you can add more voice channels to your current system without much work. With earlier systems, you would need new cables and wiring. This is not the case when upgrading a SIP trunk, which is quick and easy. You can also keep your existing hardware.

Lower costs

This flexibility doesn’t, however, mean that you need to spend a lot of money. Quite the opposite, actually. In almost all areas, SIP trunking leads to huge cost savings. Installing it is not only easier, it’s also significantly cheaper when compared to other telephony solutions. The upkeep and simultaneous use of numerous extensions cost a lot less as well. On top of this, the connection itself is generally less expensive. Depending on your provider, you may be able to save money by paying a flat rate for all your calls.

Number transfers

Telephone numbers using a SIP trunk are not location specific. Most SIP trunking providers allow you to port your number, making it easy to keep the number you currently have when switching providers. This also means that you can move your business somewhere else and keep the number that you were using at your previous location. This not only saves you money, as well as a lot of work, it also benefits your customers.

Improved customer service

If you use SIP trunking, you will be able to use both local and international numbers. This means that your customers and business partners will be able to call you conveniently and cheaply.

Connection quality

The connection quality when using a SIP trunk is usually very good. Since calls use IP technology, you can avoid additional VoIP gateways.

A modern and futuristic solution

SIP trunking has been growing for a long time and is increasingly replacing traditional solutions. It’s safe to assume that SIP trunking will completely replace ISDN and analogue phone services. IP-based telephony systems are reliable, require minimal maintenance and increase user mobility.

What are the disadvantages of SIP trunks?

Even if the advantages of SIP trunks outweigh the disadvantages in most cases, it’s worth taking a look at some (possible) disadvantages. These include:

Dependence on bandwidth

The call quality as well as other benefits of a SIP trunk are dependent on internet connection and bandwidth. If there is not enough bandwidth, the technology will be pushed to its limits. If there are problems with a connection, users may only be able to use the technology in a limited capacity, or in the worst-case scenario, they won’t be able to use it at all. For this reason, each voice channel should have at least 100 kbit/s available.

Vulnerability

Depending on the type of network, a SIP trunk may be used as an entry point for scammers. You can prevent this by using security software.

Differences between providers

A positive aspect is that there are many SIP trunk providers. However, not all will be able to meet your personal or business needs and service quality expectations. We recommend carefully comparing providers to determine which SIP solution is best for you.