R4 List six access technologies. Classify each one as residential access, company access, or mobile access. 1. Dial-up Res 2. DSL Res 3. Cable Res 4. HFC Res 5. FTTH Mobile 6. Ethernet Company
R5 Is HFC transmission rate dedicated or shared among users? Are collisions possible in a downstream HFC channel? Why or why not? They are shared and yes, that is why there is a need for a protocol to prevent it from happening.
R9 Dial-up modems, HFC, DSL and FTTH are all used for residential access. For each of these access technologies, provide a range of transmission rates and comment on whether the transmission rate is shared or dedicated? Dial-up = max 56kps Up & Down = dedicated HFC = 4/50KHzup – 1MHz down = Shared DSL = 1mbps Up- 8mpbs down = Dedicated FTTH = 2/10mbps Up - 10/20 Up down = Shared
R11 What advantage does a circuit-switched network have over a packet-switched network? What advantages does TDM have over FDM in a circuit-switched network? Circuit-switched is suitable for real-time such as voice.
R14 What is the key distinguishing difference between a tier-1 and a tier-2 ISP? Speed - Their link speeds are often 622 Mbps or higher and larger tier-1 ISPs have links in the 2.5 to 10 Gpbs range
R16 Consider sending a packet from a source host to a destination host over a fixed route. List the delay components in the end-to-end delay. Which of these delays are constant and which are variable? 1. Processing - Variable 2. Queuing - Variable 3. Transmission - Variable 4. Propagation - Constant = propagates at the propagation speed of the link.
R23 What are the five layers in the Internet protocol stack? What are the principal responsibilities of each of these layers? 1. Application: contains the network applications and application