Circuit Switching Example L= message lengths 2= arrival rate of messages R= channel rate in bits per second X= message transmission delay =L/R R must be large enough to keep X small Bursty traffic→x≤1=> low utilization Example L =1000 bytes(8000 bits) 2=1 message per second X<0.1 seconds(delay requirement) =>R>8000/0.1=80,000bps Uti| ization=8000/80000=10% With packet switching channel can be shared among many sessions to achieve higher utilizationCircuit Switching Example L = message lengths λ = arrival rate of messages R = channel rate in bits per second X = message transmission delay = L/R – R must be large enough to keep X small – B ursty tra ffic => λx << 1 => low utilization • Example – L = 1000 bytes (8000 bits) – λ = 1 message per second – X < 0.1 seconds (delay requirement) – => R > 8000/0.1 = 80,000 bps Utilization = 8000/80000 = 10% • With packet switching channel can be shared among many sessions to achieve higher utilization Eytan Modiano Slide 12