Telecommunications Structure of My Workplace

I am currently employed with the IT Department inside the corporate headquarters for 24 Hour Fitness. The telecommunications systems used in my workplace is pretty complex. 24 Hour Fitness is located here in Carlsbad, California. We have three buildings; the main one is our Corporate Administration Center (CAC), which houses our call centers. The other two buildings holds our main I.T. departments (Developers and our Network Operations Center (NOC)), with the exception of our Helpdesk and Telecom department (located in CAC). The I.T. department is responsible for making sure all our fitness clubs (about 500 of them) and our regional offices, along with corporate offices will be able to communicate seamlessly. To start with, the provider that we use is MCI. Coming in to our main headquarters is a T-3 line (dedicated phone connection supporting data rates of about 43 Mbps), divided in to three primary trunks. The three primary trunks are divided as Local (two T-1), Long Distance (two T-1), and a separate trunk for our collections center (five T-1). Two of our buildings (CAC and NOC) have two dedicated T-1 lines between them and within our NOC; an OC12 (short for Optical Carrier, speed = 622.08 Mbps) is used to guarantee communication to our clubs, field users, and our numerous regional offices. The telecom systems in my workplace are pretty extensive as described by Melody Sanchez, our Telecom/Helpdesk Manager. Located in the CAC building is a Definity G3si phone switch, which is pretty much the central host for our telecom system. The Definity G3 switch has routing tables, redundancy for failure recovery, local vectoring, and Automatic Call Distribution (ACD) are among the features of this amazing machine. For our voicemail system we have an Intuity AudixR4, which automatically erases any voicemails older than 14 days and 45 second maximum time to record a message. For conferencing we have an Avaya 48 port Multilink Conference Bridge, which has two