sip trunking

Voice Termination: Understanding Sip Trunking

As with any technical discipline, the world of telecommunications has its own lexicon of buzz phrases and mysterious acronyms. One of these you are likely to encounter is SIP – short for Session Initiation Protocol – most often in relation to SIP trunking. But what exactly is it and what benefits does it offer for businesses.

Eliminating voice termination gateways

Before we start looking at SIP trunking, we need to understand a little about more traditional phone systems. Until recently, if you had an in-house telephone system based around a PABX, you needed to have an ISDN line to link it up to the public telephone network. Alternatives included either a basic rate interface (BRI), a primary rate interface (PRI) or a PSTN gateway. With any of these methods, there was a lack of flexibility because you needed to purchase an uprated service if you wanted to expand. In addition, there were cost implications because you could end up paying for more capacity than you used.

Using SIP trunking eliminates all of these problems because it uses the internet to provide your voice calls. Typically, your internet connection will already have excess bandwidth that can accommodate voice calls without affecting your existing network traffic. Even in situations in which you need to update your connection to cope with VoIP, it’s still going to cost less than an ISDN installation and you don’t need to have separate voice and data connections. There are also benefits in that a business only need have one SIP trunking account, even with multiple sites.

Practical considerations

SIP trunking can simplify your connections and cut your costs, but it delivers a number of other benefits for your business too. You can keep your existing PABX since most modern systems can interface to IP-based systems. Alternatively, you may choose to eliminate your PABX hardware entirely and use a cloud system instead.

Increasingly, firms are moving to a more decentralised approach to work, with people encouraged to spend time working from home. SIP trunking delivers benefits here too. Used in combination with remote connectivity solutions, users that aren’t on your main site can access all of your enterprise phone system functions wherever they are located, whether working from home or in a hotel room on a business trip.

VoIP systems are capable of carrying a significant level of traffic and can be scaled to cope with expansion or changes in demand. It’s important to note, however, that if you are using the same connection for voice and data traffic, you should deploy quality of service (QoS) management to ensure that voice traffic gets prioritised and there is no loss of call quality.

We can’t leave this discussion without taking a quick look at security. Installing a firewall that is able to handle SIP traffic is essential to defend against unwanted activity. You also need to ensure that your service provider account is kept secure, with strong passwords and encryption where needed.

For further information and advice, why not contact IDT today.