NS Network Simulation and Differenciated Services Analysis

EEET1246 Advanced Computer Network Engineering

Laboratory Assignment 2 Report

Professor: Andrew Jennins ([email protected])

Tutor: Piya Techateerawat ([email protected])

Student: Xiaolin Zhang

Email: [email protected]

Student: Wilson Castillo Bautista

Email: [email protected]

Subject Code: EEET1246 Advanced Computer Network Eng.

Melbourne, Octubre 2nd,2006

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Melbourne, 2nd October, 2006

NS Network Simulation and Differentiated Services

Laboratory 2 Report

Laboratory Report

Student: Xiaolin Zhang (s3097029)

Student: Wilson Castillo (s3143667)

RMIT University © 2006

School of Electrical and Computer Engineering

Table of Contents

1 Aim......................................................................................................................................................4

2 Introduction ......................................................................................................................................4

3 Differentiated Services....................................................................................................................5

3.1 DiffServ Field Definition ...................................................................................................5

3.2 Traffic Classification.........................................................................................................6

3.2.1 Classifier.............................................................................................................................6

3.2.2 Multi-Field Classifier (MF) ................................................................................................6

3.2.3 Behaviour Aggregate Classifier (BA)............................................................................6

3.3 Meter..................................................................................................................................6

3.4 Marker................................................................................................................................7

3.5 Shaper ...............................................................................................................................7

3.6 Dropper .............................................................................................................................7

3.7 DiffServ Architecture .......................................................................................................8

3.7.1 Edge Router Responsibilities ..........................................................................................8

3.7.2 Core Router Responsibilities...........................................................................................8

3.8 Multiple RED Routers .......................................................................................................8

3.8.1 Introduction ......................................................................................................................8

3.8.2 Multiple RED Parameters................................................................................................9

4 DiffServ Simulation Using NS .........................................................................................................10

4.1.1 NS Architecture ..............................................................................................................10

4.1.2 DiffServ Support..............................................................................................................10

4.1.2.1 DiffServ Simulation Improvements...........................................................10

4.1.2.2 Defining policies .........................................................................................11

5 Results...............................................................................................................................................12

5.1 Types of traffic ................................................................................................................12

5.1.1 Premium ..........................................................................................................................12

5.1.1.1 Classifying and Marking............................................................................12

5.1.1.2 Mettering .....................................................................................................12

5.1.1.3 Shaping/Dropping .....................................................................................12

5.1.2 Gold .................................................................................................................................12


5.1.2.2 Mettering .....................................................................................................13

5.1.2.3 Shaping and Dropping .............................................................................13

5.1.3 Best Effort.........................................................................................................................13


5.1.3.2 Mettering .....................................................................................................13

5.1.3.3 Shaping and Dropping .............................................................................13

5.2 Simulation........................................................................................................................13

5.2.1 Simulation using PQ scheduler....................................................................................14

5.2.2 Simulation using LLQ scheduler...................................................................................15

5.2.3 Simulation using WFQ scheduler.................................................................................17

5.2.4 Simulation using SCFQ scheduler ...............................................................................18

6 Problems that we overcame.......................................................................................................21

7 Conclusions.....................................................................................................................................21

8 References ......................................................................................................................................22

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Table of Figures

Figure 1: Topology used in the Differentiated Services Simulation ................................................5

Figure 2: IPV4 header..............................................................................................................................6

Figure 3: IPV6 header..............................................................................................................................6

Figure 4: Traffic Conditioner in Differentiated Services ....................................................................7

Figure 5: Nam Output resulted from simulation...............................................................................13

Figure 6: Class Rate - PQ ......................................................................................................................14

Figure 7: Packet Loss - PQ ....................................................................................................................14

Figure 8: Queue Length - PQ...............................................................................................................14

Figure 9: Service Rate - PQ ..................................................................................................................14

Figure 10: Avg One-Way Dealy for EF - PQ......................................................................................15

Figure 11: Virtual Queue Length - PQ ................................................................................................15

Figure 12: EF IPVD - PQ..........................................................................................................................15

Figure 13: Goodput (Telnet and FTP) - PQ ........................................................................................15

Figure 14: Class Rate – LLQ ..................................................................................................................16

Figure 15: Packet Loss - LLQ.................................................................................................................16

Figure 16: Queue Length - LLQ ...........................................................................................................16

Figure 17: Virtual Queue Length - LLQ...............................................................................................16

Figure 18: Service Rate - LLQ...............................................................................................................16

Figure 19: EF IPVD - LLQ ........................................................................................................................16

Figure 20: Avg One-Way Dealy for EF - LLQ.....................................................................................17

Figure 21: Goodput (Telnet and FTP) - LLQ .......................................................................................17

Figure 22: Class Rate – WFQ ................................................................................................................17

Figure 23: Packet Loss - WFQ...............................................................................................................17

Figure 24: Queue Length - WFQ .........................................................................................................17

Figure 25: Virtual Queue Length - WFQ.............................................................................................17

Figure 26: Service Rate - WFQ.............................................................................................................18

Figure 27: EF IPVD -WFQ .......................................................................................................................18

Figure 28: Avg One-Way Dealy for EF - WFQ...................................................................................18

Figure 29: Goodput (Telnet and FTP) - WFQ .....................................................................................18

Figure 30: Class Rate - SCFQ................................................................................................................19

Figure 31: Packet Loss - SCFQ..............................................................................................................19

Figure 32: Queue Length - SCFQ ........................................................................................................19

Figure 33: Virtual Queue Length -SCFQ.............................................................................................19

Figure 34: Service Rate - SCFQ............................................................................................................19

Figure 35: EF IPVD - SCFQ .....................................................................................................................19

Figure 36: Avg One-Way Delay for EF - SCFQ .................................................................................20

Figure 37: Goodput (Telnet and FTP) - SCFQ....................................................................................20

Figure 38: Statistics - PQ........................................................................................................................20

Figure 39: Statistics - LLQ.......................................................................................................................20

Figure 40: Statistics - WFQ.....................................................................................................................20

Figure 41: Statisctics – SCFQ ................................................................................................................20

Figure 42: Statistics – WF2PQp .............................................................................................................21

Figure 43: EF IPVD - SFQ ........................................................................................................................21

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NS Network Simulation and Differentiated Services Analysis

1 Aim

The aim of this lab is to investigate the impact of routing policy and traffic policing at the

edge and core routers inside a common network. Moreover, it is the main aim to

understand the Differentiated Services architecture. For instance, to achieve this aim it is

necessary to simulate a network topology behaviour in order to analyse how the Quality of

Service behave under a variety of Differentiated Served configurations.

2 Introduction

Nowadays internet is by the fact one of the most important sources of information and

communication integration between users around the world. Moreover, the information

sent through the network is divided into packages which travel from one point to another

with the same treatment, e.g. without any differentiation between them. This is the basic

Quality of Service Model that governs most of the networks today and it is called Best Effort

model. For instance, all connections get the same treatment with unpredictable delays

and data loss and consequently, they cannot support real time applications.

To solve this issue the Internet Engineering Task Force has created the differentiated

services architecture which deals with traffic management to provide scalable services

differentiation on the internet. As it is stated in their first paragraph:

“Differentiated services enhancements to the Internet protocol are intended to

enable scalable service discrimination in the Internet without the need for per-

flow state and signaling at every hop. A variety o services may be built from a

small, well-defined set of building blocks which are deployed in network

nodes.” (www.ietf.org, 2006/10/01).

To investigate the real effects of differentiated services nodes in the network it is important

to compare the variety of options that give differentiated service enhancements. For

instance, it is necessary to simulate the network behaviour of different scenarios. And this is

done by using NS (Network Simulator) that is a discrete event simulator targeted at

networking research (www.isi.edu, 2006/10/01).

The network we are investigated in this lab consists of 1 core router, 2 edge routers with 5

user hosts that cluster around them. There are two applications running on this network:

each user host will connect randomly to any other user host to do peer-peer file serving, FTP

over TCP as the underlying transport protocol; as well as each user host interacts with its

local core router for web access using UDP over TCP. We defined to use this architecture

because by definition the intelligence of the differentiated services architecture is located

at the edge router of the network (Jimenez and Altman, 2006), in our example e1 router:

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Figure 1: Topology used in the Differentiated Services Simulation

3 Differentiated Services

Differentiated Services (Diffserv) is an IP QoS architecture based on marking packets at the

edge of the network according to user requirements. According to the marks, packets are

treated differently at the network’s nodes using different parameters.

According to RFC2474 (www.ietf.org, 2006/10/01), the way that packets are marked is

done by the definition of a SLS (Service Level Specification) that is a combination between

SLA (Service Level Agreement; between a provider and a customer) and TCA (Traffic

Conditioning Agreement – rules applied to the traffic).

3.1 DiffServ Field Definition

As described above each packet that enters to a DS network needs to be marked

according to certain conditions; this mark is called Differentiated Services Code Point

(DSCP), (Andreozzi, 2001). This field is shown in the following graphs:

0 4 8 16

Vers4 Head

Len Type of Service Total Length

Identification Flags Fragment Offset

Time to Live Protocol Header Cheksum

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Source Address

Destination Address

Options

PAD

Figure 2: IPV4 header

0 4 12

Vers6 Traffic Class Flow Label

Payload length Next

Header Hop Limit

Source Address

Destination Address

Figure 3: IPV6 header

3.2 Traffic Classification

Traffic classification is done according to the following mechanisms: Classifier, Meter,

Markers and Shaper/Dropper: (Rodriguez, Gatrell, Karas and Peschke, 2001)

3.2.1 Classifier

The main function of the classifier is to discriminate packets according to their header: It is

defined two kinds of classifiers

3.2.2 Multi-Field Classifier (MF)

They are able to classify according to a combination of several fields like IP source address,

IP destination address, IP source port and destination port.

3.2.3 Behaviour Aggregate Classifier (BA)

This classifier only is able to discriminate packets according to the DS Field in the IP packet

as described in Figure 2 and Figure 3.

3.3 Meter

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The function of the meter is to analyse is the incoming packet fits some of the internal

profiles that are configured in the router. Some of these meters could be:

� Average Rate Meter

� EWMA (Exponential Weighted Moving Average Meter).

� TSW2CM

� TSW3CM

� TB (Token Bucket)

� srTCM (Single rate Three Colours Marker)

� trTCM (Two rate Three Colours Marker)

3.4 Marker

The function of the marker is to set the DS field according to a pattern.

3.5 Shaper

The function of the shaper is to delay some or all of the incoming packets

3.6 Dropper

The dropper discard packets that do not fit any profile inside the router. The way packet

are discarded is done by an algorithm:

� RIO Coupled (RIO-C)

� RIO De-coupled (RIO-D)

� Weighted RED (WRED)

� Drop on threshold

The previous concepts could be viewed in the following graph

Figure 4: Traffic Conditioner in Differentiated Services

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Once the packet have been conditioned it is necessary to schedule it in order to transmit it

to the following node in the network. Several schedulers are defined in the standard. The

following is a short list of some of them:

� RR (Round Robin)

� WRR (Weighted Round Robin)

� WIRR (Weighted Interleaved Round Robin)

� PQ (Priority Queuing)

� WFQ (Weighted Fair Bandwidth sharing) also known packet by packet

� WF2Qt

� SCFQ

� SFQ (Start Time Fair Queuing)

� LLQ (Low Latency Queuing)

3.7 DiffServ Architecture

The DiffServ architecture has three major components:

� The policy, which is specified for each edge and core device through the Tcl scripts,

determines which traffic receives a particular level of service in the network, this

task may depend on the behaviour of the source of the flow, e.g, its average rate

and its burstiness.

� Edge routers and

� Core routers.

3.7.1 Edge Router Responsibilities

� Examining incoming packets and classifying them according to policy specified by

the network administrator.

� Marking packets with a code point that reflects the desired level of service.

� Ensuring that user traffic adheres to its policy specifications, by shaping and policing

traffic.

3.7.2 Core Router Responsibilities

� Examining incoming packets for the code point marking done (DSCP) on the

packet by the edge routers.

� Forwarding incoming packets according to their markings. (Core routers provide a

reaction to the marking done by edge routers.)

3.8 Multiple RED Routers

3.8.1 Introduction

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In Multiple RED routers, the DifferServ architecture provides QoS by dividing traffic into

different categories, marking each packet with a code point that indicates its category,

and scheduling packets according to their code points. In a NS DiffServ network, not more

than four classes of traffic are defined, each of which has three drop precedences

resulting in different treatment of traffic within a single class.

In order to differentiate between packets belonging to the same class, three virtual queues

are implemented in each of the four queues, one for each drop precedence. A packet

with lower drop precedence is given better treatment.

Therefore, each of the 12 combination of the four flow calss and the three internal priority

levels within a flow correspond a code point that a packet is given when entering the

network. But in practice, not all queues and all priority groups need to be implemented.

The three virtual RED buffers in each physical queue allowing enhancing its behaviour are

RIO-C, the probability of dropping low priority packets is based on the weighted average

lengths of all virtual queues and the probability of dropping a high priority packet is based

only on the weighted average length of its own virtual queue, by default, the MRED mode

is set to RIO-C; in contrast, in RIO-D, the probability of dropping each packet is based on

the size of its virtual queue; another one is the WRED (Weighted RED) in which all

probabilities are based on a single queue length (Jimenez and Altman, 2006).

3.8.2 Multiple RED Parameters

To Set DS RED parameters from Edge1 to Core, we use the command:

$qE1C set numQueues_ m

Where m can take values between 1 and 4. $qE1C identifies the edge Router object;

To specify the number of virtual queues, we use the command in the queue and

precedence levels settings:

$qE1C setNumPrec 0 2

Queue 0, two levels of precedence

RED parameters are then configured for one virtual queue using the command in the

shaping/dropping:

$qE1C configQ $queueNum $virtualQueueNum $minTh $maxTh $maxP

It thus has 5 parameters:

1. the queue number,

2. virtual queue number,

3. min th ,

4. max th and

5. max p .

For example, “$dsredq configQ 0 1 10 20 0.10”, specifies that physical queue 0/virtual

queue 1 has a minth value of 10 packets, a maxth value of 20 packets, and a maxp value

of 0.10.

For the mean packet size (in bytes), this command is used in the shaping/dropping:

$qE1C meanPktSize 1300

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In addition, commands are available which allow us to choose the scheduling mode

between queues, such as:

$qE1C setSchedularMode SFQ

$qE1C addQueueWeight 0 3

The above pair of commands sets the scheduling mode to SCFQ, and then sets the queue

weight for queue o to 3. SFQ stands Start-time Fair Queueing.

4 DiffServ Simulation Using NS

4.1.1 NS Architecture

A simulation is defined by an OTcl script. Running a simulation involves creating and

executing a file with a “.tcl” extension, such as “example.tcl.”

A Tcl ns script:

� Defines a network topology (including the nodes, links, and scheduling and routing

algorithms of a network).

� Defines a traffic pattern (for example, the start and stop time of an FTP session).

� Collects statistics and outputs the results of the simulation. Results are usually written

to files, including files for Nam, the Network Animator program that comes with the

full ns download.

For example, the statement:

$ns at 0.5 “$tcp start”, which is translated into event: at 0.5 seconds into the simulation,

starts up a TCP source.

4.1.2 DiffServ Support

The NS module has some limitations when the user needs to simulate differentiated services

behaviour (Andreozzi, 2001):

� It is not possible to mark traffic on per packet type.

� It is not possible to define meter for aggregate meter.

� It is not possible to drop out-of-profile traffic.

4.1.2.1 DiffServ Simulation Improvements

In our simulation example we are using the improvement made by Sergio Andreozzi

(http://www.cnaf.infn.it/~andreozzi/, 2006/10/01) The following changes are applied to

improve router modelling capabilities in DiffServ module (Andreozzi, 2001):

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� Schedulers: the targets are to speed the scheduler addition by encapsulating the

scheduler mechanism in its own class and to increase the number of available

schedulers

� marker and meter: the target is to enable marking on a per-packet basis and to

decouple marking from metering

� dropper: the target is to enable a drop out-of-profile traffic capability on a drop

precedence level basis

Moreover, the following set of functionalities for measurement and performance analysis

were added:

� One-Way Delay (OWD): the target is to enable end-to-end one-way delay

computation. instantaneous, average, minimum and frequency distributed OWD

will be provided for UDP-based traffic

� IP Packet Delay Variation (IPDV): the target is to enable the delay variation

computation in a destination node for packets belonging to the same micro-flow;

instantaneous, average, minimum and frequency distributed IPDV will be provided

for UDP-based traffic

� Queue length: the target is to enable queue length checking at a script

� language level; it will be provided on a per queue and per drop level precedence

basis

� Maximum burstiness for queue 0: the target is to enable maximum enqueued

� packets checking for queue 0; this queue is typically used for priority traffic

� Departure rate on a per queue basis and on a per queue and per drop level

precedence basis

� Received packets, transmitted packets, early dropped and late dropped packets

on a DSCP basis, both absolute and percentage values

� TCP Goodput on a DSCP basis, instantaneous and frequency distributed TCP

Round-Trip Time on a DSCP basis, instantaneous and frequency distributed TCP

Windows Size on a DSCP basis: the target is to enable computation of performance

parameters for TCP-based traffic to understand the level of differentiation on an

aggregate level

4.1.2.2 Defining policies

� All flows having the same source and destination are subject to a common policy.

� A policy specifies at least two code points.

� The choice between them depends on the comparison between the flow's target

� and its current sending rate, and possibly on the policy dependent parameters

(such as burstiness).

� The policy specifies meter types that are used for measuring the relevant input

� traffic parameters. And a packet arriving at the edge device causes the meter to

update the state variables corresponding to the flow, and the packet is then

marked according to the policy.

� The packet has an initial code point corresponding to the required service level; the

� marking can result in downgrading the service level with respect to the initial

required one.

� A policy table is used in ns to store the policy type of each flow. Not all entries are

� actually used. To update the policy table, the ''addPolicyEntry'' command is used.

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� An example is:

$edgeQueue addPolicerEntry [$n1 id] [$n8 id] trTCM 10 200000 1000 300000 1000

Here we added a policy for the flow that originates in $n1 and ends at $n8. If the TSW

policers are used, one can add at the end the TSW window length. If not added, it is taken

to be 1sec by default.

5 Results

In the following simulations the following parameters are defined:

� BW between s(x) nodes and e1 router is 100 MB

� BW between e1 node and core is 100kB

� EF (Expedited Traffic) cir (commited information rate) = 500kB

� EF (Expedited Traffic) cbs (Commited Burst Rate) between = 1300 bytes.

� Number of queues = 3

5.1 Types of traffic

5.1.1 Premium

Queue Number 0

Queue Size = 50

VIrutal queues = 2

5.1.1.1 Classifying and Marking

Any traffic coming from node s(0)

DSCP (Diffserv Code Point) = 46.

5.1.1.2 Mettering

Entry Policy Token Bucket 500000 1301

Policer Token Bucket.

5.1.1.3 Shaping/Dropping

DROP 0

5.1.2 Gold

Queue Number 1

Queue Size = 150

Virtual queues = 3

AF11 telnet

AF!2, AF13 for ftp


Any telnet DSCP (Diffserv Code Point) = 10

Any ftp DCP = 12

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5.1.2.2 Mettering

telnet : DUMP: No policy for telnet.

ftp: TSW2CM 500000 (500KB) when ftp exceeds this value packets are dropped.

5.1.2.3 Shaping and Dropping

RIO-C

5.1.3 Best Effort

Queue Number 2

Queue Size = 100

Virtual queues = 2


No rules, all packets that do not fit other profile will be considered for best effort policy.

5.1.3.2 Mettering

Entry Policy Token Bucket 500000 1301

Policer Token Bucket.

5.1.3.3 Shaping and Dropping

DROP 2

5.2 Simulation

The output result simulation from nam is showed in the following graphic:

Figure 5: Nam Output resulted from simulation.

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The simulations were done varying the way the traffic is scheduled. For instance, we

change the algorithm in each simulation. The following show the different outputs for each

different scheduler algorithm:

5.2.1 Simulation using PQ scheduler

Figure 6: Class Rate - PQ

Figure 7: Packet Loss - PQ

Figure 8: Queue Length - PQ

Figure 9: Service Rate - PQ

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Figure 10: Avg One-Way Dealy for EF - PQ

Figure 11: Virtual Queue Length - PQ

Figure 12: EF IPVD - PQ

Figure 13: Goodput (Telnet and FTP) - PQ

5.2.2 Simulation using LLQ scheduler

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Figure 14: Class Rate – LLQ

Figure 15: Packet Loss - LLQ

Figure 16: Queue Length - LLQ

Figure 17: Virtual Queue Length - LLQ

Figure 18: Service Rate - LLQ

Figure 19: EF IPVD - LLQ

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Figure 20: Avg One-Way Dealy for EF - LLQ

Figure 21: Goodput (Telnet and FTP) - LLQ

5.2.3 Simulation using WFQ scheduler

Figure 22: Class Rate – WFQ

Figure 23: Packet Loss - WFQ

Figure 24: Queue Length - WFQ

Figure 25: Virtual Queue Length - WFQ

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Figure 26: Service Rate - WFQ

Figure 27: EF IPVD -WFQ

Figure 28: Avg One-Way Dealy for EF - WFQ

Figure 29: Goodput (Telnet and FTP) - WFQ

5.2.4 Simulation using SCFQ scheduler

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Figure 30: Class Rate - SCFQ

Figure 31: Packet Loss - SCFQ

Figure 32: Queue Length - SCFQ

Figure 33: Virtual Queue Length -SCFQ

Figure 34: Service Rate - SCFQ

Figure 35: EF IPVD - SCFQ

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Figure 36: Avg One-Way Delay for EF - SCFQ

Figure 37: Goodput (Telnet and FTP) - SCFQ

Statistics

Figure 38: Statistics - PQ

Figure 39: Statistics - LLQ

Figure 40: Statistics - WFQ

Figure 41: Statisctics – SCFQ

Packets Statistics

=======================================

CP TotPkts TxPkts ldrops edrops

-- ------- ------ ------ ------

0 47522 0.21% 99.79% 0.00%

10 1097 100.00% 0.00% 0.00%

12 5439 91.29% 0.00% 8.71%

14 139 58.99% 0.00% 41.01%

46 2816 100.00% 0.00% 0.00%

50 24614 0.00% 0.00% 100.00%

----------------------------------------

All 81627 11.10% 58.10% 30.80%

Packets Statistics

=======================================


-- ------- ------ ------ ------

0 46717 28.22% 71.78% 0.00%

10 1132 100.00% 0.00% 0.00%

12 2745 89.14% 0.00% 10.86%

14 31 93.55% 0.00% 6.45%

46 2802 100.00% 0.00% 0.00%

50 25277 0.00% 0.00% 100.00%

----------------------------------------

All 78704 24.90% 42.61% 32.50%

Packets Statistics

=======================================


-- ------- ------ ------ ------

0 48279 59.89% 40.11% 0.00%

10 1171 100.00% 0.00% 0.00%

12 2493 89.09% 0.00% 10.91%

14 10 100.00% 0.00% 0.00%

46 2823 41.27% 0.00% 58.73%

50 24048 0.00% 0.00% 100.00%

----------------------------------------

All 78824 42.47% 24.57% 32.96%

Packets Statistics

=======================================


-- ------- ------ ------ ------

0 46881 40.07% 59.93% 0.00%

10 1130 100.00% 0.00% 0.00%

12 4085 90.33% 0.00% 9.67%

14 17 100.00% 0.00% 0.00%

46 2835 41.41% 0.00% 58.59%

50 25460 0.00% 0.00% 100.00%

----------------------------------------

All 80408 30.84% 34.94% 34.22%

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Figure 42: Statistics – WF2PQp

Figure 43: EF IPVD - SFQ

6 Problems that we overcame

The main problem found in this lab is to get a complete manual of NS. However to master

NS software it is required a considerable amount of time between trying and testing.

Internet is a very valuable source of information.

7 Conclusions

The way that traffic is treated in the network is affected in a direct way by the scheduler

chosen. As can be seen in the simulations when PQ was chosen the Service rate for EF

traffic did not seem to be affected. Instead, 100% of the packets were passed from e1 to

the core. Contrary, when SCFQ scheduler was chosen EF traffic dropped by the network

raised dramatically to 58.59%.

Other effects of changing the scheduler is the queue length behaviour in the entire

simulation. With PQ scheduler EF queue length remain almost empty but with SCFQ the

length queue raised dramatically to almost 30 packets.

In our simulations it could be seen that the number of packet successfully delivered are

quite independent of the CIR (Committed Information Rate).

Another important parameter that affects packet dropping is the CBS (Commited Burst

Specification). This parameter means that every packet that is above this value will be

dropped in the network. This parameter could be used when the network administrator has

several constrains about bandwidth in the network.

Queue length parameter affect the probability of dropping packets. For instance, it is

important to have a small queue length for every data flow.

Packets Statistics

=======================================


-- ------- ------ ------ ------

0 47946 57.99% 42.01% 0.00%

10 1204 100.00% 0.00% 0.00%

12 2495 88.82% 0.00% 11.18%

14 17 100.00% 0.00% 0.00%

46 2829 41.22% 0.00% 58.78%

50 24143 0.00% 0.00% 100.00%

----------------------------------------

All 78634 41.21% 25.62% 33.17%

Packets Statistics

=======================================


-- ------- ------ ------ ------

0 47593 59.45% 40.55% 0.00%

10 1094 100.00% 0.00% 0.00%

12 2601 89.39% 0.00% 10.61%

14 10 100.00% 0.00% 0.00%

46 2819 41.26% 0.00% 58.74%

50 24474 0.00% 0.00% 100.00%

----------------------------------------

All 78591 41.85% 24.55% 33.60%

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8 References

Andreozzi S, 2001, DiffServ simulations using the Network Simulator: requirements, issues and solutions,

Master’s Thesis.

Carpenter B and Nichols K, 2002, Differentiated Services in the Internet, Proceedings of the IEEE, vol.

90, no. 9, sept. 2002

Altman E, 2006, Simulating Diffser (Differentiated Services), Lecture Notes, January-February 2006,

Inria.

Pieda P, Ethridge J, Baines M and Shallwani F, 2000, A Network Simulator Differentiated Services

Implementation, Open IP, Nortel Networks.

Stevens, W. Richard. 2001, TCP/IP Illustrated, Volume 1, Addison-Wesley Professional Computing

Series, Indianapolis.

Rodriguez A, Gatrell J, Kara J and Peschke Roland, 2001, TCP/IP Tutorial and Technical Overview,

ibm.com/redbooks.

Hao J, Puliu Y and Delin X., 2003, A Dynamic-Weight RED Gateway, Wuhan University, Hubei.

Sahu S, Towsley D and Kurose J, 1999, A Quantitative Study of Differentiated Services for the Internet,

Global Telecommunications Conference, Globecom’99, Massachusetts.

Documents

NS Network Simulation and Differenciated Services Analysis