4. (TCO 10) What’s the standard that governs the layer 2 prioritization? What’s the standard that governs the layer 3 prioritization? When a packet arrives at a router, which field of the packet’s IP header is used by the router to make prioritized local forwarding decisions? When a frame arrives at a switch, which field of the frame’s Ethernet header is referred to by the switch for priority settings? (Points : 10)            Â

 

Question 5.5. (TCO 9) Use the Erlangs and VoIP Bandwidth Calculator at http://www.erlang.com/calculator/eipb/ to complete the following question.   The ABC Inc. is planning to lease a 1000 Kbps (i.e., 1 Mbps) frame relay connection between two PBXs from two branch locations. The audio codec used on the trunk is G.729A with a 20-millisecond packet duration. Assume the targeted call blocking probability for ABC Inc. is 1% (i.e., 0.01). How much traffic volume/load (in Erlangs) can this trunk support?   120 call attempts, with an average call duration of 10 minutes during the Busy Hour have been observed on the connection. What’s the current traffic volume/load (in Erlangs) on this trunk connection? Compare the current traffic volume/load to the supported traffic volume/load calculated above. Does the frame relay trunk have enough capacity to support the current traffic volume/load? (Points : 10)            Â

 

Question 6.6. (TCO 11) ABC Inc. is re-evaluating the end-to-end delay budget of its cross-continent VoIP services. Name at least two components (i.e., devices or processes) that contribute to the end-to-end latency budget. Suggest, in one paragraph, two methods that could help ABC Inc. reduce the end-to-end latency of its cross-continent VoIP services. (Points : 10)            Â