1) You have business sites with 1 Gbps Ethernet LANs in both Chicago and New York. You are considering two different possible WAN services to connect them:
A leased line / dedicated OC3 circuit between the sites
An OC3 access line to an Internet Service Provider (ISP) in Chicago, and another OC3 access line to an ISP in New York. Each of these ISP access line connects to public Internet service. a. (5 points) Which of these two possible WAN services would give you the smallest average packet delivery delays? Why? b. (5 points) Which of these two WAN services would be the most expensive? c. (5 points) For the leased line service, what throughput (in bps) would you expect for file transfers from Chicago to New York?
2) (5 points) Each SONET STS-1 frame contains 18 bytes of Line Overhead. The full STS1/OC-1 transmission rate is 51.84 Mbps. What is the Line Overhead rate of the OC-1? That is, how many bits per second (out of the 51.84 Mbps) contain Line Overhead information?
3) (5 points) How many T1 data channels can be multiplexed into a single SONET OC-24 using Virtual Tributaries?
4) Your company has a headquarters in Madison, WI, and two branch offices in Chicago, IL, and St Paul, MN. Your interconnect all three offices using leased T3 (DS3) services as shown below. You can use the 1-year term pricing (no discounts) at http://www.att.com/public_affairs/long_distance_news/product_reference_and_pricing_gu ide/DataSection4.pdf a. (5 points) What is your one-time installation charge for these DS3 circuits? b. (5 points) What is your total monthly cost for these DS3 circuits, including monthly recurring charge (MRC) and interoffice channel charge? Chicago Madison St. Paul 2
5) An 80 Kbps digital voice channel is carried across an ATM network on a Constant Bit Rate PVC using AAL1. Show your calculations for each answer below. a. (5 points) On average, how many ATM cells are sent over this PVC each second to carry this voice channel? b. (5 points) On average, how many total bits per second (including cell headers) must be sent to carry this voice channel?
6) (5 points) You have two buildings that are 300 meters apart and they have high-quality copper twisted-pair data cable running between them. Considering all the different DSL transmission standards that are discussed in the class notes, what is the maximum bit rate you can send between these building using some type of DSL technology?