There are many benefits to adopting IP trunking to use for your company's or institution's multiple phone lines. Are you an organization that does a lot of work or research online? Then adopting IP trunking is a logical step to take. The main reason is that it combines your data/Internet network and your phone network. That could potentially save your company hundreds of dollars a month on maintenance fees because the phone and Internet system are now the same system. It could also save you money on employment costs (so long as your existing IT guy or gal knows how to use an IP trunking system). Cheaper communications is one of the best things IP trunking has going for it. Many Internet service providers are also phone service providers, and they're the ones offering IP trunking. Since they run all channels of communication, these companies are empowered to offer "bundling" discounts, reducing your communication rates even further.
One of the main reasons consumer-level VoIP has taken off is because of its flat-fee pricing structure. Services like Vonage charge a single rate for unlimited phone calls, local and long distance included. Because VoIP and IP trunking convert voices to data, you're not technically using the phone lines to make long distance calls -- you're just transmitting data. As far as bandwidth is concerned, your phone call is the same as an e-mail. In short, long-distance charges drop to as low as 2 cents per call, and then just a single monthly fee for each of your IP trunk users, about $20 to $30 per trunk [source: Bandwidth.com]. Another bonus is that because it's a system based on remote data transfer anyway, you can even have users at multiple locations use the same trunk. You don't have to pay for multiple IP trunking servers.
But what if you don't think IP trunking is established enough to use for your primary communication needs? Well, it's always a good idea to have a backup. IP trunking is easy enough to use, and with the equipment you already have around in the office (phones, computers), it can be used to provide network redundancy. If landlines ever go down, but the Internet is still up, it can help you out. Because it's not phone-based in a DSL, T1 or cable setup, you can simply enable VoIP-based calling, resuming communications productivity immediately.