ns-tutorial

ƒƒƒƒƒThe Network Simulator-ns-2Claudia Canali17/11/03Tutorial OutlinePart INS fundamentalsWired worldWalk-thru an example NS scriptPart IIVisualization tools & other utilitiesHelp and references1ƒƒƒƒƒƒWhat Is NS?Started as variant of REAL in 1989Developed at UC BerkelyDiscrete event, packet level simulatorWritten in C++ with Otcl frontendWired, wireless and emulation modesLink layer and up for most wiredAdditional lower layers for wirelessPlatformsMost UNIX and UNIX-like systemsLinuxFreeBSDSunOS/SolarisHP/SGI (with some tweaking)Windows 95/98/NT/ME/2000Tips on build availableHowever validation tests don’t work2ƒƒƒƒzzArchitecture in NSObject-oriented (C++ and Otcl)Algorithms over large data sets, per packet handling in C++ Configuration, “one-time” stuff in Otcl Fast to run, quick to re-configureFine grained object compositionC++ and OTcl SeparationC++ for “data”Per packet actionOTcl (Object Tcl Extensions) for controlConfiguration, “one-time” task+ Compromise between composibility and speed– Learning and debugging3OTcl and C++: The DualityPure OTclPure C++objectsobjectsC++/OTcl split objectsC++ OTclnsBasic Tcl(Tool Command Language)set a 43set b 27proc test { a b } {set c [expr $a + $b]set d [expr [expr $a - $b] * $c]for {set k 0} {$k < 10} {incr k} {if {$k < 5} {puts “k < 5, pow = [expr pow($d, $k)]”} else {puts “k >= 5, mod = [expr $d % $k]”}}}4Basic OTclClass Mom set mom [new ...