Virtual PBX vs. Self-hosted PBX Systems

PBX systems allow you to configure extensions, customer management systems, automated attendants, call redirects, and more to route calls within your organization. These operations are handled through a private branch exchange (PBX) server. Virtual PBX services will configure, maintain and host your exchange server offsite and you simply purchase IP phones and an Internet connection to interact with a web-based administration panel. The self-hosted PBX brings the internal (on-premises) exchange server. Benefits and compensation vary, but in general, virtual PBX services are for small businesses and self-hosted PBX systems are for medium to large businesses with a high volume of phones. You can use analog phone lines or digital VoIP with Self-Host PBX. Virtual PBX services are limited to VoIP. PBXSystems.org focuses solely on the cost savings (typically 50%) associated with enterprise-grade VoIP communications.

Prices

The general consensus is that virtual PBX services are ideal for small businesses with only 1-10 employees. With virtual PBX, you share the third-party exchange server with other people, therefore, you share the hardware and maintenance costs. You should identify your needs and carefully research your preferred virtual PBX provider. Costs typically range from $30 to $120 per month for full packages (minutes included). Extensions may or may not be free depending on the provider. Your marginal cost will increase compared to self-hosted PBX systems as you add more users.

Virtual PBX systems will also provide you with SIP and DID trunks instead of protecting your own. However, they may limit the number or channels or simultaneous calls your phone number can make (services vary).

For self-hosted PBX systems, you’ll need a server (with a PCI data port), configuration software (open source available), broadband connection (t1 handles 30 concurrent calls), and potentially a firewall or gateway. VoIP rate plans are provided through Internet Telephony Service Providers (ITSPs) and will charge at least $15/SIP Trunk/month and $1/DID/month (rate plans and packages will vary by provider). As a general rule, you should reserve channels (DID, etc.) for 1/3 of your employees. If you have 300 employees, not all of them will be on the phone at all times. Find out a secure means of necessary simultaneous calls. Each service provider will handle terminology (SIP, DID, channels, etc.) differently. Contact your support department with specific requirements/questions, such as:

• “Do we need 20 simultaneous incoming calls to our toll free number and 2 simultaneous calls to our local number?”
• “We need approximately 5,000 incoming minutes to our toll free number, 1,000 outgoing minutes to Australia and 1,200 outgoing minutes to our satellite office in Germany.”
• “If our phone systems fail, can we redirect incoming traffic to another phone?”
• “Do we have 4 different numbers, with ‘x’ number of staff handling ‘x’ concurrent calls on each number?”
• “How is it handled and how much do you charge for port numbers in and out of your system?”

Bottom line: If you need more than 25 concurrent calls (75+ employees), consider a self-hosted PBX system. If you are not familiar with PBX systems, please spend at least 1 month researching your options before purchasing equipment and services (check compatibility and features). You will need compatible phones, server/software, firewall, data/voice Internet service, and SIP/DID providers.

Hardware

Many of those self-hosted PBX hardware can cost up to $60,000. However, do your research on what your business needs, as many hardware vendors can sell a complete PBX setup (supported phones and server/software installed) for smaller businesses in the $2500 area.

Depending on your needs and volume, a commercial grade pipeline can cost up to $600/month. For the most part, simultaneous calls are limited to your bandwidth (say 23 simultaneous channels/T1). Also, some SIP providers will require a static IP. With Virtual PBX, businesses can use a standard data Internet connection which may not be practical for large sales/support centers. However, both IP-PBX systems allow you to share the same bandwidth for both data and voice. Be sure to adjust the QoS (Quality of Service) settings to prioritize voice and avoid dropped calls and poor sound quality.

For both systems, you can use SIP-enabled IP phones or softphones. You can also use a traditional phone, but you will need an ATA adapter or a gateway for VoIP service (check interop closely). Self-hosted systems may require a SIP firewall.

other

With Virtual PBX, you are using a server and service that is out of your control and putting yourself at risk of security and reliability.

With self-hosted PBX, you select your ITSP (Internet Telephone Service Provider) for SIP trunks. You are not limited to one provider. You can set up rules within Asterisk, for example, to send certain calls to one ITSP and other calls to another (maximize profits for individual providers). Also, you can have backup ITSPs in case a SIP provider goes down (you can also set automatic error handling rules for this). Virtual PBX providers do not allow such configurability, although one would assume that their internal back-end processes have such backup mechanisms in place.

Many, but not all, virtual PBX systems will limit concurrent calls by number. What is your technical capacity? Do you have the time and capacity to maintain a self-hosted PBX system? If you do, even with fewer users, a self-hosted PBX system could save costs. However, if you don’t have time, use the virtual PBX in the meantime according to a strict profit/savings analysis.