Chapter 10: Mini-Case 1 - Cathy's Collectibles

MINI-CASES
I. Cathy’s Collectibles
Your cousin Cathy runs a part-time business out of her apartment. She buys and sells collectibles such as antique prints, baseball cards, and cartoon cells and has recently discovered the Web with its many auction sites. She has begun buying and selling on the Web by bidding on collectibles at lesser-known sites and selling them at a profit at more well-known sites. She downloads and uploads lots of graphics (pictures of the items she’s buying and selling). She is getting frustrated with the slow Internet access she has with her 56-Kbps dial-up modem and asks you for advice. DSL is available at a cost of $60 per month for 1.5 Mbps down and 384 Kbps up. Cable modem service is available for a cost of $50 per month for 1.5 Mbps down and 640 Kbps up. Wireless DSL is available in her apartment building for $45 per month for 1.5 Mbps down and 256 Kbps up. Explain the differences in these services and make a recommendation. DSL is available at a cost of $60 per month for 1.5 Mbps down and 384 Kbps up
This type of DSL is called asymmetric DSL (ADSL). This type uses frequency separation multiplexing to generate three split channels over the one local loop circuit. One channel is the conventional voice telephone circuit. A second channel is a moderately high-speed simplex data channel downstream from the carrier’s end office to the customer. The third channel is a somewhat slower duplex data channel mainly utilized for upstream from the purchaser to the carrier’s end office. ADSL is called asymmetric for the reason that its two data channels have varied speeds. Each of the two data channels are further multiplexed by time division multiplexing so they can be further subdivided. (Fitzgerald 345)

Cable modem service is available for a cost of $50 per month for 1.5 Mbps down and 640