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How Many SIP Trunks Do I Need?

SIP Trunking: SIP Trunk Pricing (SIP Trunk Cost)

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How Many SIP Trunks Do I Need?

VirtualPBX SIP Trunking Configuration - How Many SIP Trunks Do I Need?For businesses with their own private branch exchanges (PBXs), it’s a common question: How many SIP trunks do I need if I want to send my call traffic through the internet?

The quick and simple answer is that most businesses will only need one SIP trunk. Further examination of this topic shows that one SIP trunk corresponds with one PBX. Since most companies only own one PBX, they only need one SIP trunk to handle their call traffic.

Stick with us for an explanation of how VirtualPBX SIP Trunking works and why an uncomplicated setup of a single trunk can give your business everything it needs to move to an IP-based call management platform.

What is a SIP Trunk?

SIP trunking services allow your business to fundamentally switch the way in which it connects your phone calls. Traditional, on-site PBX servers usually handle calls through a primary rate interface (PRI), which is a method of connecting your PBX to the public switched telephone network.

PRI Lines

The inflexible – and often expensive – nature of PRI lines are typically what urge businesses to move to IP-based telephony. PRI lines can only handle 23 concurrent calls. Therefore, if your large business or call center wants to regularly complete (both inbound and outbound combined) more calls than that number, or if you have peaks in call volume during a particular season, you will need to purchase an additional PRI. This would be necessary whether your need one additional call slot or the full 23.

SIP Trunks

SIP trunks replace PRI lines, so it’s not uncommon for us to hear How many SIP trunks do I need? when speaking to customers. Yet despite one technology replacing the other, SIP and PRI have several fundamental differences.

Instead of sending your call traffic through the public telephone network, SIP trunks instead manage calls through a private IP-based system. VirtualPBX offers this service and makes it easy for you to manage the phone numbers that are available for reaching your business. We offer an online portal for management of your trunks and full visibility into the system you have purchased.

SIP trunks are also more flexible than PRI because of their ability to handle a theoretically limitless number of concurrent calls. While a PRI can only take groups of 23 calls, SIP Trunking plans from VirtualPBX allow you to add as many lines as you need. There is no limit to which you can add extra individual channels, and there’s never any need to purchase large groups of channels at a single time. You can also remove lines at any time, so you never pay for what you don’t need.

Our base package start with 10 channels (one call per channel) and five burstable channels to handle any overflow during peak hours. Burstable channels allow for overflow in call volume and are available at no extra charge. They help with unexpected call surges and provide a bit of padding to your expected call volume. We want you to be covered when you need to handle more call traffic than usual.

VirtualPBX SIP Trunking Dashboard

How Many SIP Trunks Do I Need?

While, as discussed previously, you probably only need one SIP trunk for your business, you should understand why that’s so before jumping into this IP-based system.

We say that most businesses only need one SIP trunk because most businesses only have one PBX. If you have multiple locations, each with their own PBX server, you may choose to link those locations with a single VirtualPBX SIP Trunking account. However, when that sort of process is completed, it would still be technically correct to say that you have 2, 3, 4, or more SIP trunks – one for each PBX that’s connected in this manner.

Advantages to a Single Trunk

SIP trunks make sense for businesses that want to reduce their calling rates when they have completed a contract for PRI lines. These lines can get expensive and, as we’ve mentioned, they are inflexible with their number of included lines, so you might be paying more than what you need. A single SIP trunk that attaches to a your single PBX server means you’re able to keep your existing hardware, save money on your ongoing expenses, and only have a minimal set of upkeep for the entire system.

Additionally, setup for VirtualPBX SIP Trunking is easy. You only need to order our service and then point your PBX to our service. Our online SIP Trunking dashboard lets you enter your static IP address or your SIP URI. The connection between our service and your PBX is then created, and you can begin making calls.

Disadvantages to More Than One Trunk

While it is possible to use more than one SIP trunk to connect your whole business, we typically mention that, in these situations, it makes more sense to switch your business to a VirtualPBX VoIP Plan. Why would you switch to VoIP?

VirtualPBX Ring GroupsWhen more than one PBX server is involved, you can double or triple (or more) the upkeep for your hardware because, of course, you will be maintaining more than one piece of server equipment.

Multiple locations can also benefit greatly from the features available in a VoIP Plan, including advanced call routing through Ring Groups or ACD Queues Pro and easy setup of new user extensions, Voicemail boxes, Audio Conferences, Call Recording, and many other features that your existing PBX setup may not contain. You might also be paying third parties an extra fee for those other services.

Talk to Us About SIP Trunking

While you probably only need one SIP trunk to connect your PBX server to the internet, it’s definitely worth a conversation with our team to discuss your situation and your needs.

We’re happy to get you established with VirtualPBX SIP Trunking. That said, we’re also excited to save you even more money by switching your office(s) to a VoIP plan that offers those enterprise features listed above. Start your conversation today.

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