Should your next phone system be digital or VoIP?

One of the biggest decisions in picking your new phone system is going digital vs IP (VoIP/SIP). If you believe the IP PBX manufacturers (like this article), they have all the advantages over digital, but we think they’re a bit biased.

You may be wondering of course, what’s the difference at all? Digital phone systems are the traditional PBXs your office likely has if you bought your phone system in the 90s or 2000s. Basically each extension connects using a dedicated wire to the PBX and speaks a proprietary digital protocol. In an IP PBX the phones sit on your LAN and communicate to the PBX via an IP protocol like SIP or MGCP. Each has its advantages and disadvantages. We’ve been working on both for about a decade and here’s our thoughts on each.

If you have a digital PBX today, you’re almost certainly wired to get a new digital PBX. An IP system may require expensive LAN upgrades – ideally a PoE switch with VLANs or separate voice and data ethernet wiring to each desk. There are also solutions like Phybridge to get IP phones over digital wiring, but that cost far exceeds just doing digital phones. We think the advantage here is digital unless your only wiring is a single ethernet drop to each desk.

IP phones have the advantage of being easily moved from one desk to another, however most digital phone systems have “station relocation” which can do that by entering a few codes. IP phones can also be taken home and work like they’re in the office. Depending on your need, IP phones have an advantage here.

Digital phones are the epitome of reliability – as long as the wire isn’t damaged and the PBX is up things will work. IP phones are a lot more complex – things like packet loss, duplexing, broadcast storms, IP address conflicts, etc can make your phones not work. Our experience is IP phones just have more room for problems. Also IP phones often involve two vendors – your IT vendor running the LAN and phone vendor, leading to finger pointing and slower problem resolution. Digital has the advantage here.

IP phone systems like to tout their feature sets like voicemail to email, CTI (computer telephony integration), attendant console software, etc as unique to IP systems. The truth is new digital systems can have all those features as well. Some IP systems also lack common digital PBX features like BLF, intercom, paging, etc. I’d call features a tie – it will depend on the specific system.

Ease of Management
IP phone systems generally are managed with an easy to use web interface. Modern digital systems are generally managed…with an easy to use web interface. Its true old digital phone systems were difficult to manage, but no longer. Management is a tie.

Vendor Lock In
SIP has the advantage of being an open standard, you can generally attach a SIP phone to any SIP PBX. The problem is feature sets with vary, along with manageability, compatibility, and reliability. We’ve found PBXs with matching branded phones just work better – a vendor delivering the whole solution can make and support the solution better. Vendor lock in is a great thing when you pick the right vendor. This is a matter of preference, but we’ll call this a draw as well – IP PBXs can have vendor lock in too and that can be a good thing.

VoIP Cost Savings
VoIP phone service over the public internet can save some businesses money on their monthly phone bills, this will of course vary by each business’s location and calling pattern. But VoIP services aren’t limited to only IP PBXs – an inexpensive converter can attach VoIP service to traditional digital phone systems. VoIP phone services are also riskier than traditional telecom – they depend upon the quality of your internet connection. Again, we think this is a draw.

Bottom line we’ve seen IP phone systems have some advantages and digital other advantages. Rather than pick, our preference is a hybrid – some modern systems do both letting you pick the best of each system. You can have the robustness and wiring ease of digital phones in office with the flexibility of IP phones remotely. You can pick analog, digital/PRI, or SIP (VoIP) phone service depending on the best thing for your office.