Assignment: Data and PBX Physical Layer Cabling Design

A building you plan to use as an office has four floors; each floor is a rectangle 1000 ft. long and 300 ft. wide.  The vertical separation between the floors is 20 ft.  Each floor has 20 large offices and 40 small offices, 6 conference rooms and some open spaces for printers, kitchen etc.  Every large office has a total of 8 data outlets for computers and other data equipment; the smaller offices have 6data outlets.  The conference rooms each have 20 data outlets.  In addition there are a total of 20 data outlets in the open areas for printers and other equipment.  The rooms and outlets are distributed uniformly and have the same pattern on all the floors. You have the opportunity to work with the architect to locate the switch closets for the data network based on your network design. You plan to use CAT 5e copper UTP cabling for your horizontal wiring i.e. the wiring on each floor for data outlets as well as telephones.  For telephony, the vertical wiring is expected to be a set of 100 wire copper cables.  You want to have a cost-effective layout that delivers good performance, so you plan to follow best practices for building wiring.

Answer the following questions about the layer1/layer network design in the building:

a) You want to minimize the number of switch closets on each floor to save on costs.  How many layer 2 data switch closets must you have on each floor in the buildingto have satisfactory data performance and where will you locate these on the floor?                   

b) If you use 48 Port, layer 2 switches (48 line side ports and 4 trunk ports) in each closet, how many of these switches will you need in each of the closets?              

c) You have a server room on the first floor where you want to locate the main building Layer 2 switch that connects to all the other switches.  In addition, this switch connects to 5 servers collocated with it in the same room.  Draw a diagram of your building L2 switches interconnection architecture including the switch in the server room.                                 

d) If you also had a TDM PBX in the server room, and digital telephone set outlets near the data ports on each floor, how would you architect your telephone wiring?  How many telecom closets (for voice communications) will you need on each floor? Assume the line interface on the PBX uses one copper pair per digital telephone set and can support a maximum range of 5000 ft.

e) Draw a neat sketch of the voice and data cabling arrangement on any one floor of the building based on the answers above.