[SOLVED] One important issue in designing Ethernet lies

One important issue in designing Ethernet lies in making sure that if a computer transmits a frame, any other computer that attempts to transmit at the same time will be able to hear the incoming frame before it stops trans- mitting, or else a collision might go unnoticed. For example, assume that we are on the earth and send an Ethernet frame over a very long piece of category 5 wire to the moon. If a computer on the moon starts Transmitting at the same time as we do on the earth and finishes transmitting before our frame arrives at the moon, there will be a collision, but neither computer will detect it; the frame will be garbled, but no one will know why. So, in designing Ethernet, we must make sure that the length of cable in the LAN is shorter than the length of the shortest possible frame that can be sent. Otherwise, a collision could go undetected.
a. Let’s assume that the smallest possible message is 64 bytes (including the 33-byte overhead). If we use 100 Base-T, how long (in meters) is a 64-byte message? While electricity in the cable travels a bit slower than the speed of light, once you include delays in the electrical equipment in transmitting and receiving the signal, the defective speed is only about 40 million meters per second. (First calculate the number of seconds it would take to transmit the frame then calculate the number of meters the signal would travel in that time, and you have the total length of the frame.)
b. If we use 10GbE, how long (in meters) is a 64-byte frame?
c. The answer in part b is the maximum distance any single cable could run from a switch to a computer in an Ethernet LAN. How would you overcome the problem implied by this?
2. Pat’s Petunias:
You have been called in as a network consultant by your cousin Pat, who operates a successful mail-order lower business. She is moving to a new office and wants to install a network for her telephone operators, who take phone calls and enter orders into the system. he number of operators working varies depending on the time of day and day of the week. On slow shits, there are usually only 10 operators, whereas at peak times, there are 50. She has bids from different companies to install (1) Wi-Fi or (2) a switched Ethernet 100Base-T network. She wants you to give her some sense of the relative performance of the alternatives so she can compare that with their different costs. What would you recommend?
3. Eureka!
Eureka! is a telephone-and Internet-based concierge service that specializes in obtaining things that are hard to find (e.g., Super Bowl tickets, first-edition books from the 1500s, and Fabergé eggs). It currently employs staff members who work 24 hours per day (over three shits), with usually five to seven staff members working at any given time. Staff members answer the phone and respond to requests entered on the Eureka! website. Much of their work is spent on the phone and on computers searching on the Internet. hey have just leased a new office and are about to wire it. They have bids from different companies to install (a) a 100Base-T network or (b) a Wi-Fi network. What would you recommend? Why?
4. Tom’s Home Automation:
Your cousin Tom runs a small construction company that builds custom houses. He has just started a new specialty service that he is offering to other builders on a subcontracting basis: home automation. He provides a complete service of installing cable in all the rooms in which the homeowner wants data access and installs the necessary networking devices to provide a LAN that will connect all the computers in the house to the Internet. Most homeowners choose to install a DSL or cable modem Internet connection that provides a 12–25 Mbps from the house to the Internet. Most homeowners choose to install a DSL or cable modem Internet connection that provides a 12–25 Mbps from the house to the Internet. Tom has come to you for advice about whether he should continue to offer wiring services (which often cost $50 per room) or whether wireless is a better direction. What type of LAN would you recommend?
5. Sally’s Shoes:
Sally Smith runs a shoe store in the mall that is about 30 feet by 50 feet in size, including a small office and a storage area in the rear. The store has one inventory computer in the storage area and one computer in the office. She is replacing the two cash registers with computers that will act as cash registers but will also be able to communicate with the inventory computer. Sally wants to network the computers with a LAN. What sort of LAN design would you recommend? Draw a picture.
6. South West State University:
South West State University installed a series of four Wi-Fi Omni-directional Aps spread across the ceiling of the main floor of its library. The main floor has several large, open areas plus two dozen or so small offices spread around the outside walls. The WLAN worked well for one semester, but now more students are using the network, and performance has deteriorated significantly. What would you recommend that they do? Be sure to support your recommendations.
7. Household Wireless:
Your sister is building a new two-story house (which measures 50 feet long by 30 feet wide) and wants to make sure that it is capable of networking her family’s three computers together. She and her husband are both consultants and work out of their home in the evenings and a few days a month (each has a separate office with a computer, plus a laptop from the office that is occasionally used). The kids also have a computer in their play- room. They have several options for networking their home:
a. Wire the two offices and playroom with Ethernet Cat 5e cable and put in a 1000Base-T switch for $40.
b. Install one Wi-Fi AP ($85) and put Wi-Fi cards in the three computers for $50 each (their laptops already have Wi-Fi).
c. Any combination of these options. What would you recommend? Justify your recommendation.
8. Ubiquitous Offices:
Ubiquitous Offices provides temporary office space in cities around the country. They have a standard office layout that is a single floor with outside dimensions of 150 feet wide by 150 feet long. The interior is drywall offices. They have 1000Base-T but want to add wireless access as well. How many APs would you buy, and where would you put them? Draw the office and show where the Aps would go.
9. ABC Warehouse:
ABC Warehouse is a single-floor facility with outside dimensions of 100 feet wide by 350 feet long. The interior is open, but there are large metal shelving units throughout the building to hold all the goods in the warehouse. How many APs would you buy, and where would you put them? Draw the warehouse and show where the Aps would go.
10. Metro Motel:
Metro Motel is a four-story motel on the outskirts of town. The outside dimensions of the motel are 60 feet wide by 200 feet long, and each story is about 10 feet high. Each floor (except the ground floor) has 20 rooms (drywall construction).here is a central corridor with room son both sides. How many APs would you buy, and where would you put them? Draw the motel and show where the APs would go.

Required:
1. (a) Let’s assume that the smallest possible message is 64 bytes (including the 33-byte overhead). If we use 100Base-T, how long (in meters) is a 64-byte message? While electricity in the cable travels a bit slower than the speed of light, once you include delays in the electrical equipment in transmitting and receiving the signal, the effective speed is only about 40 million meters per second.
(b) If we use 10GbE, how long (in meters) is a 64-byte frame?
(c) The answer in part b is the maximum distance any single cable could run from a switch to a computer in an Ethernet LAN. How would you overcome the problem implied by this?
2. On slow shifts, there are usually only 10 operators, whereas at peak times, here are 50. She has bids from different companies to install (a) a shared Ethernet 100Base-T network, or (b) a switched Ethernet 100Base-T network. She wants you to give her some sense of the relative performance of the alternatives so they can compare that with their different costs. What would you recommend?
3. Eureka has just leased a new office and are about to wire it. They have bids from different companies to install (a) 100 Base-T network, or (c) a WI-FI network. What would you recommend? Why?
4. Should he continue to offer wiring services, which often cost $50 per room) or is wireless a better direction? What type of LAN would you recommend? Why?
5. Sally wants to network the computer with a LAN. What sort of LAN design would you recommend? Draw a picture.
6. With a wireless network installed in the library of South West State University, how should they protect the network performance?
7. Is your sister’s new house going to need any special wiring?
8. How many access points would you buy for the Ubiquitous Office? Where would you place them?
9. How many access points would you buy for the Ubiquitous Office? Where would you place them?
10. How many access points would you buy for the Ubiquitous Office? Where would you place them?

Question: One important issue in designing Ethernet lies