SIP Trunking Pros and Cons

On premise SIP trunking vs hosted services by external vendors has become a long-standing debate within the VoIP industry. To shed more light on the differences between the two alternatives, let us examine SIP trunking closely. Before we delve into the benefits and drawbacks of SIP trunks, we need to have a clear idea of what it is and how it is implemented.

What Is SIP Trunking?

Anyone who is familiar with enterprise phone systems will be able to grasp the concept of SIP trunks readily. In a traditional business phone set up, the company will purchase PRI lines from the phone operator which connects the organization with the external phone network. These lines are in turn hooked up to a PBX system.

The basic setup is the same with SIP trunks except that the physical lines between the phone operator and the company is replaced by an Internet connection to the ITSP (Internet Telephony Service Provider). In this case, the term ‘trunks’ is a misnomer since the physical cables are replaced with virtual data connections. However the term is freely used within the VoIP industry.

Hardware Required for SIP Trunks

In many cases, businesses simply switch out their old PRI lines for the corresponding or equivalent SIP trunks. However the rest of the hardware should also be upgraded or changed to support the SIP protocol for VoIP calling. It often means that the organization has to change the PBX system to an IP-PBX that supports SIP. Employees will need to be provided with either headsets or IP desk phones. Soft phone applications can also be downloaded and installed on desktops and mobile devices.

SIP Trunking Pros and Cons

An important aspect of any technology change is – how much it will cost to upgrade to or implement the new system? While some industry experts posit that cost is actually a benefit for SIP trunks, others argue that it is a drawback. So which exactly is it? The answer comes down to how you view the total cost of implementation.

Some costs are variable or recurring expenses on a periodic basis – weekly or monthly. These costs are directly proportional to the volume of calls i.e. the more calls you make, the higher your monthly bill. Although the per call rate can differ between vendors, the savings are not that significant between hosted VoIP and SIP trunks.

However there are also fixed costs that come into play. These are expenses that are absolutely necessary, regardless of the size of the company or complexity of the features required. In general, they do not change based on volume of calls. They do not recur periodically and payment is needed up front.

Therefore some organizations view the cost of SIP trunks as an advantage over the long term while some companies – especially small businesses – view it as a drawback since they may not have enough financial resources for initial investment. To sum up, SIP trunks require initial investment but the total cost over a decade is very less.

SIP Trunk Benefits – Highly Customizable

One of the main drawbacks for hosted services is limited customizability for enterprises. While most consumers are satisfied with the default options, organizations often find it necessary to customize service delivery for their own particular requirements. With SIP trunks, businesses can choose and control what features are available to whom within the organization. Features can be enabled or disabled without having to wait for an external vendor. The upgrade cycle, security updates and software patches are all within the control of the organization.

SIP Trunking Benefits – Increased Productivity

Not many people are aware of all the productivity benefits that are made possible by SIP trunking and in particular, by unified communications. Easy access to customers, partners and suppliers can make a world of difference in collaborative projects. Even within a particular project team, virtual meetings and video messaging can easily replace long drawn out meetings thus saving precious time.

SIP Trunk Drawbacks – Requires Maintenance

On the flipside, on premise deployments mean that the organization needs to have the required expertise to maintain the systems. If something goes wrong, you cannot simply call up the vendor for customer service or technical troubleshooting. While some companies get around this by outsourcing the maintenance and servicing, it can quickly become expensive.

SIP Trunking Drawbacks – Advanced Planning and Engineering

Organizations that want to deploy SIP trunks need to plan in advance certain aspects such as required capacity, average and peak traffic estimates, network load etc. The type of SIP architecture – centralized was is distributed – should also be decided. Besides all this, security is a significant concern with VoIP systems nowadays. All this has to be managed in house, rather than an external party taking care of it for you.

As we can see, after being cognizant of the SIP trunking pros and cons, it can be a great choice for some companies while being financially infeasible for others.  Thus you should select a system that best meets your requirements.