Traditional Telephony is passing. For years, every company had a Pbx (a Private Branch exchange), which was like a mini-phone company on the company's premises. More and more, companies are switching to mobile platforms, Voip-enabled phones, and even communication over your computer and an Internet connection (such as Lync from Microsoft). There are many vendors who will outsource this functionality for you, either doing it all and forwarding to your mobile phone or providing a unified inbox and communications via an application, such as Lync, which is provided as part of Office 365. Either way, the use of phones is decreasing and, while they may never completely go away, they may do more and more over standard Ethernet, making it an It task instead of telephony administration. Now would be a good time to study up on Voip and networking, if you wish to stay in this line of work, or consider broadening your skills further in case the company outsources all these functions.