Eli the Computer Guy

Info

• Level: Beginner
• Presenter: Eli the Computer Guy
• Date Created: August 2, 2010
• Length of Class: 54 Minutes

Tracks

• Telephone Systems

Prerequisites

• None

Purpose of Class

• This class introduces students to the basic components of telephone systems.

Topics Covered

• Public Switched Telephone Network
• Central Offices
• Trunk Lines
• PBX and Voicemail Systems
• PBX Stations
• Voicemail Subcribers

Class Notes

1. Introduction
   1. Telephone systems are not complicated if you understand how they work.
2. A Word on VoIP
   1. VoIP is not a telephone system
3. PSTN
   1. PSTN – Public Switched Telephone Network is like the Internet, but for telephone communication
   2. NADP – North American Dialing Plan – Is the system for routing telephone calls.
   3. Central Office – All telephone lines connect to a local central office
4. Trunk Lines
   1. Every Trunk Line has a telephone number
   2. A Trunk Line allows for 1 incoming or outgoing call.  You can have far more telephones in a building then you have trunk lines.
   3. Incoming Trunk lines are setup in Hunt Groups.  If the main phone number is busy the call is automatically forwarded to the next number in the Hunt Group
   4. Incoming Hunt Groups are setup by your local telephone company.
   5. Outgoing calls can be routed to use selected trunk lines.  This in configured in your PBX.
5. PBX and Voicemail
   1. The PBX routes telephone calls
   2. The Voicemail system provides all audio messaging. (Voicemail boxes, Message Boards, and Auto Attendant Messages)
6. Stations
   1. All devices that connect to the PBX are “Stations”.  This includes telephones, call boxes, intercom systems, etc.
   2. There are 2 types of stations; Analogue and Digital.
   3. Analogue and Digital stations have to be connected to appropriate ports on the PBX.  An analogue phone cannot connect to a digital port and vice versa.
   4. Almost all fax machines and phones you buy at retail stores are analogue.  If your new fax machine does not work it may be because it’s plugged into a digital line.
7. Subscribers
   1. Subscribers are users of the Voicemail system.
   2. Subscribers do not have to have stations
   3. Voicemail ports are the number of connections to the Voicemail system at any one time.  This includes not just people retrieving their voicemail, but also incoming calls that connect to Auto Attendant messages.
8. Final Thoughts
   1. Be careful before you touch!  Most older telephone and voicemail systems were administered using a phone keypad, NOT and computer interface.  If you mess something up it can be very difficult to rebuild a deleted Auto Attendant or such.

Resources

• North American Numbering Plan
• PSTN – Wikipedia

Eli the Computer Guy (437 Posts)

Eli the Computer Guy has 16 years experience in technology being the guy to fix "it". From the Army, to building out new satellite offices for the enterprise, to running his own shop with 9 full time employees Eli has real world experience with almost all systems that technicians will be working with. Eli has 1600 hours of formal technical beyond his Bachelors Degree in Criminal Justice on technologies ranging from Avaya PBX/ Audix to Microsoft, Red Hat Linux, MySQL, Cisco and much more.