My experiences involve having worked in call centres, understanding how queues are used, and at Kraus where I administered the Meridian 1 phone system. In the latter, I implemented a new system, and through that project, learned the use of technologies, and how to manage a project from the proposal stage through negotiation and design, to implementation and training.
I am familiar with PBX's and Norstar key systems. One particularly useful application to have for Nortel products is Phone Master (by an Irish company named Phoneware). It allows you to effect changes and moves without calling in a technician.