Performance Evaluation and Enhancement of Mobile Node Using MIK Essay


Chapter 4


4.1 Introduction

NS2 is associate open-source simulation tool that runs on Linux, it ‘s a discreet event machine targeted at networking analysis and provides significant support for simulation of routing, multicast protocols and information sciences protocols, like UDP, TCP, RTP and SRM over wired and radio ( local and orbiter ) webs. Its several approvals that build it a great tool, like support for multiple protocols and therefore the capableness of graphically particularisation web traffic. In add-on, NS2 supports many algorithms in routing and line uping. Local routing and broadcasts are a portion of routing algorithms. Line uping algorithms embody honest queuing, shortage round-robin and FIFO.

NS is associate object oriented machine, written in C++ , with associate OTcl translator as a frontend. The machine supports a class hierarchy in C++ ( besides referred to as the compiled hierarchy during this papers ) , and an indistinguishable class hierarchy inside the OTcl translator ( besides referred to as the taken hierarchy during this papers ) . The 2 hierarchy’s square step closely associated with every other ; from the user’s position, there ‘s a matched correspondence between a class within the taken hierarchy and one within the compiled hierarchy, the footing of this hierarchy is that the class Tcl Object. Users produce new machine objects through the translator ; these objects square step instantiated inside the translator, and square step closely reflected by a corresponding object within the compiled hierarchy. The taken class hierarchy is automatically established through schemes outlined within the class TclClass. User instantiated objects square step reflected through schemes outlined within the class TclObject.

NS2 is extensively utilized by the networking analysis community. It provides significant support for simulation of communications protocol, routing, multicast protocols over wired and radio ( local and orbiter ) webs, etc. The machine is event-driven and runs in a really non-real-time manner. It consists of C++ nucleus schemes and uses Tcl and Object Tcl shell as interface allowing the computing machine file ( simulation book ) to explicate the theoretical account to imitate.

Users will sketch arbitrary web topologies composed of nodes, routers, links and shared media. A smart set of protocol objects will so be hooked up to nodes, sometimes as agents. The machine suite collectively includes a graphical perceiver referred to as web energizer ( NAM ) to assist the users get extra penetrations sing their simulation by visualising package hint information.

NS is an juncture driven web machine developed at UC Berkeley that simulates manner of information sciences webs. It implements web protocols like communications protocol and UPD, traffic supply behaviour like FTP, Telnet, Web, cosmic microwave background and VBR, router waiting line direction mechanism like Drop Tail, RED and CBQ, routing algorithms like Dijkstra, and more. NS collectively implements multicasting and a few of the mac bed protocols for computing machine web simulations.

4.2 A Short History

NS2 started as a discrepancy of the $ 64000 web machine in 1989 ( see Resources ) . REAL could be a web machine originally supposed for the existent the dynamic behaviour of flow and congestion direction strategies in packet-switched information webs.

NS2 is associate degree object-oriented machine developed as a portion of the VINT undertaking at the University of American province in Berkeley. The undertaking is funded by authorities bureau together with XEROX Palo Alto research centre ( PARC ) and Lawrence Berkeley National Laboratory ( LBNL ) .

NS2 is accessible on many platforms like Linux, Ubuntu, FreeBSD, SunOS and Solaris. NS2 collectively builds and runs underneath Windows.

Large scenarios benefit from big sums of memory. Additionally, NS2 requires the undermentioned bundles to run these scenarios Tcl has released Tcl8.3.2, Tk has released Tk 8.3.2, OTcl has released OTcl 1.0a7 and besides TclCL has released TclCL 1.0b11.

4.3 C++ and OTCL Duality

In this agency, the controls of the C++ objects country unit given to OTcl. It’s collectively come-at-able to have member maps and variables to a C++ connected OTcl object. The objects in C++ that do n’t hold to be controlled during a simulation or internally utilized by another object do n’t hold to be connected to OTcl. Likewise, associate grade object ( non within the information way ) is wholly enforced in OTcl.


Fig 4.1: C++ and OTcl: The Dichotomy

In this agency, the controls of the C++ objects country unit given to OTcl. It’s collectively come-at-able to have member maps and variables to a C++ connected OTcl object. The objects in C++ that do n’t hold to be controlled during a simulation or internally utilized by another object do n’t hold to be connected to OTcl. Likewise, associate grade object ( non within the information way ) is wholly enforced in OTcl.

Figure 5.1 shows associate degree object hierarchy illustration in C++ and OTcl. One factor to detect within the figure is that for C++ objects that have associate grade OTcl linkage organizing a hierarchy, there ‘s an indistinguishable OTcl object hierarchy awfully merely like that of C++ .

NS was inbuilt C++ and provides a simulation interface through OTcl, associate grade object-oriented parlance of Tcl. The user describes a configuration by composing OTcl books, so the most ns plan simulates that topology with mere parametric quantities.

The NS2 makes usage of level Earth theoretical account within which it assumes that the ambiance is level with none lifts or depressions. But the existent universe will hold geographical options like vales and mountains.NS2 fails to capture this theoretical account in it.

Many research workers have planned the add-ons of latest theoretical accounts to NS2.Shadowing Model in NS2 makes an effort to capture the shadow impact of signals in existent universe, nevertheless will that inaccurately.NS2 ‘s shadowing theoretical account does n’t believe about correlativities: a true tailing impact has sturdy correlativities between 2 locations that country unit near one another. Shadow fading ought to be sculptured as a 2 dimensional log-normal random method with exponentially disintegrating spatial correlativities.

4.4 Screenshot of Network Animator

Fig 4.2: Network Animator Window

NS energizer window is shown in the above figure 4.2 which can be used to see the connexion between the Mobile and the web towers, it shows the motion package drops which take topographic point during simulation.

4.5NIST’s Media Independent Handover faculty


Wireless web types Handover are off two types, Horizontal handovers besides called Homogenous Handover and Vertical handovers besides called Heterogeneous handovers. If Handover take topographic point in same entree engineering ( WiFi & A ; lt ; – & A ; gt ; WiFi ) or ( WIMAX & A ; lt ; – & A ; gt ; WIMAX ) is Horizontal and if Handover takes topographic point within the different entree engineering ( WiFi & A ; lt ; – & A ; gt ; WiMAX ) or ( WIMAX & A ; lt ; – & A ; gt ; WIFI ) is Vertical Handover. If Longer the handover continuance, so higher the package bead and hapless QoS [ 7 ] . IEEE with 802.21 MIH addressed perpendicular handover, which separates the different entree engineering in a nomadic device from the upper beds in the protocol stack. NIST has provided the 802.21 MIH add-on faculties [ 3 ] for web simulator ( ns2.29 ) . These module support the two of the MIH maps, events and bids.

4.5.2Supporting Technologies of 802.21 in ns-2

Ns-2.29 supports the entree engineerings in IEEE 802.21 scenarios are: WiMAX ( 802.16 ) , Wi-Fi ( 802.11 ) , UMTS and Ethernet ( 802.3 ) .

4.5.3Execution of Nodes with Multiple Interfaces in ns-2

NS-2 does non back up the heterogenous multiple interfaces of a nomadic node ( MN ) , because node construction do non needfully follow the same as the one defined in the basic theoretical account by external bundles. Hence to decide this issue, NIST add-on faculty created the construct of multiFace node besides called ace node, which is a nomadic node which can associate to other nomadic nodes, these interfaces for the multiFace node, and the multiFace node can be viewed as as “supernode” . This construct is illustrated in Fig. 4.1.


Fig. 4.1: High Level View of MultiFace Node


Fig. 4.2: Power boundaries defined in NS2

The interface nodes activate the events and forwards them to the ace node. The MIH Users on the ace node are frequently ready to register and to have these events.

4.5.4Power Boundaries are frequently outlined in Wifi and WiMAX Cells

In order to descry power boundaries which may be utilized in the simulation, 3 variables are outlined in ns-2.29, that is shown in Fig. 5.2. Thesiss variable are frequently outlined as:

CSTresh:accustomed outline the minimal power degree to feel wireless packages and collectively exchange the mac bed, if mac bed is idle so it are frequently switched to occupy,

RX Tresh:are frequently accustomed outline the minimal power degree to have wireless packages with error free ;

pr_limit:are frequently perpetually equal or superior to one and is employed within the equation ( RX Tresh ) * ( pr_limit ) , so this equation are traveling to be determining the minimal power degree that Associate in Nursing interface senses Link taking topographic point event before triping.

In the above figure Fig 4.2, shows the ability boundaries between WLAN and WiMAX base station with its vary wherever the highest most bed is Cs thresh_ , in-between bed is rx thresh_ and besides the interior bed is rx thresh_ * Pr limit_ .

Dept. of CSE, VKIT 2014-20151