Lab: VoIP Traffic Engineering

Task 1-Calculate the VoIP traffic load in access trunks to the Internet.

Q1. What is the number of call-attempts during the busy hour at the company's location?

Q2. What is the traffic load in Erlangs during the busy hour? Show calculation and units.

Q3. What in the dimension of traffic measurement unit Erlang?

Task 2-Calculate the number of SIP trunks and access link bandwidth required for VoIP calls to the Internet.

Q4. What is the difference between a completed call and a call attempt?

Q5. What is the number of SIP trunks (lines from the online calculator) required to meet company's need?

Q6. What access bandwidth (Kbps from the online calculator) is required to connect the company's location to the Internet?

Q7. If T1 bandwidth is 1.544 Mbps, T3 bandwidth is 44.736 Mbps, and there are 28 T1 in a T3, what access connection(s) does the company need to lease in terms of T1 and/or T3? Show the calculation.

Q8. Enter a screenshot below showing the results from the Erlang-to-VoIP bandwidth calculator.

Task 3-Calculate the number of backup access channels to the PSTN.

Q9. How many analog lines does the company need to subscribe from a TSP? Include a screenshot below that shows the calculator results.

Q10. Assume that each analog line can carry 1 Erlang of voice traffic. What is the utilization of the PSTN trunks if an Internet failure occurs during busy hour? Show the calculation.