(For more resources on Telephony, see here.)
Some smaller businesses might be able to get away with just using Skype. As a software client, Skype can be easily installed on individual computers. Since most workstations these days have a microphone built in to the monitor, a simple headset should suffice in getting up and running with Skype, along with a nominal fee per month to set up an account with privileges to call regular telephones.
One problem with this method, however, is the way that Skype can hog your bandwidth. Skype is a peer-to-peer application that not only uses your system’s bandwidth in order to make phone calls; it also acts as a node for other phone calls across its own distributed network. Essentially, Skype also has the capability in its peer-to-peer system that can cause it to inadvertently hog bandwidth, which could cause your office to experience traffic problems.
There are a series of useful Active Directory group policies you can enact to try to such as using ListenPortPolicy to try to lock down ports as well as using DisableApiPolicy to block bandwidth-eating third party APIs, but having to manage this system may be a bit too tumultuous, especially if you have a large amount of machines on your system.
In a network that has larger scale, using Skype is probably not feasible. Technology titans such as Cisco and HP have systems complete with phones and special switches that can be easily implemented into a network; although this option requires a lot more upfront expense and time, if your system is at such a scale for such a service the long-term cost savings will be immense. Because IP phones are just like devices that use Organizational Units in Active Directory, you’ll be able to better place policies on them.
You’ll inevitably have bandwidth issues using VoIP, but the difference between an application like Skype and IP telephone hardware is that you’re dealing with separate devices that disparately use bandwidth instead of trying to use group policies to manage software that is on a workstation. That means using your network performance management system to be able to control things like jitter and packet loss by placing a priority on your VoIP traffic.
Bottom line: depending on the size of your network, you have options on leveraging VoIP and Active Directory for your infrastructure. Either way you look at it, you’ll be able to save cash on phone calls by switching to an IP-based solution.
Further resources on this subject:
- Setting Up OpenVPN with X509 Certificates [Article]
- Installing OpenVPN on Linux and Unix Systems [Article]
- Networking with OpenVPN [Article]
- Installation of OpenSIPS 1.6 [Article]
- Configuring sipXecs Server Features [Article]
