Queuing Models in NS2

M/M/1 is a system with poisson arrival time, servicing exponentially and a queue of unlimited capacity and type of FIFO Queue. This is the simplest queuing system.  NS2 supports various distributions like pareto, exponential, constant, unifrom, etc to handle the network dynamics and metrics. So it is very easy to test the given network link to monitor a given queue using any of these queuing models. The listing 3 and 4 are monitoring the link when DropTail queue is used with a capacity of finite and infinite. Listing 13.3 uses infinite capacity and Listing 13.4 uses Finite capacity The output screen shot is shown below the scripts for further understanding
Listing 3 – M/M/1 Queuing Model #new Simulator creation set ns [new Simulator] #trace file creation for capturing the UDP data set tf [open out.tr w] $ns trace-all $tf
#setting the exponential distribution param set lambda 30.0 set mu     33.0
#creation of nodes set n1 [$ns node] set n2 [$ns node] #The queue limit is 1Lakh as the capacity is infin…

proc directory in Linux

If by any chance, if you want to know about the processor, memory, IO Memory, Ports, etc about the system/CPU. Then you can look into the folder /proc in Linux. There are various files that tells you the information about the CPU.
Some Examples
if you want to know about the CPU Information, go to the terminal and try this
# cat /proc/cpuinfo
For memory information
# cat /proc/meminfo
For IO Memory information
# cat /proc/iomem
if you want to see how long the system is up can be seen using the file uptime
# cat /proc/uptime
(The above will list two numbers, one being the uptime of the system and other being uptime for all the cores of the processor)
and other information like scheduling, filesystems, etc can be seen from the /proc folder

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