The document discusses modeling user, application, and network behaviors to analyze and estimate requirements for computer networks. It describes developing models to characterize behaviors like session durations, data sizes, and traffic patterns. Simulation modeling allows testing designs virtually before physical implementation. Models of varying complexity can predict performance metrics like utilization, delay, and capacity to help optimize network design.

1. DESIGN AND
MANAGEMENT
OF COMPUTER
NETWORKS
CSK
DEPARTMENT OF
INFORMATION
TECHNOLOGY
OXFORD
ENGINEERING
COLLEGE - TRICHY

2. UNIT - II

3.  It representing how users and applications use the
network. In order to develop and understand their
requirements.
 It consists
 Estimates of user session duration.
 The number of active sessions.
 Data sizes(word sizes range 16 bit, 128 bit)-size of data.
 Detailed models(Description) of user and application
behavior.

4.  A session Is a
 semi-permanent interactive information / or
 dialogue / or
 conversation inter change.
 Interaction between a computer and the user .
 Ex: Login History(login /logout timestamps)
 LAST ACCESS.

5.  Session duration:
 Average amount of time that visitors spend on the site
each time they visit.
 Ex: Total duration of all sessions (in seconds)
 Timestamps : (OCT 27.10.2014 10:00:10:10 AM)

6.  When a user arrives to a webpage, a session variable is
created for the user .(temp)
 All websites that allow you to show the number of
visitors use database.(webpage history)
 (visitors count)
 Ex:
 Session Expiration: Internet Login.
 TIMESTAMP(11:11:11 - 27.10.2014)

7.  Data sizes(size of the Bytes/bits)(Storage)- max /min
 Detailed models of user and application behavior.
 Types of the behavior:
 USER Behavior
 APPLICATION Behavior
 NETWORK Behavior

8.  Definition:
 Simulation modeling is the process of creating and
analyzing a digital prototype of a
physical model(equipment) to predict its performance
in the real world.
 Digital Prototyping gives conceptual design,
Engineering, Manufacturing, Departments the ability to
virtually explore a complete product before it’s built.
 Example: AutoCAD, CAM, matLAB
 Autodesk Simulation Mechanical

9.  Physical Prototyping is the process of making a
physical representation of an idea.
 Digital Prototyping:
 Digital Prototyping gives conceptual design,
engineering, manufacturing, and sales and marketing
departments the ability to virtually explore a complete
product

12.  Simulation modeling is used to help designers and
engineers understand whether, under what conditions,
and in which ways a part could fail and what loads it can
withstand.
 Developing models or simulations of user, application,
and network behavior useful in predicting, determining
or estimating requirements and data flows.
 Models can range from Easy, Simplistic, Complex and
time consuming.
 It is not a ‘physical implementation’

13.  Modeling and simulation are useful throughout the ANALYSIS PROCESS for
characterizing user, application, and existing network behaviors.
 Simulation modeling allows designers and engineers to avoid repeated building
of multiple physical prototypes.
 To analyze designs for new or existing parts. Before creating the physical
prototype, users can virtually investigate many digital prototypes. Using the
technique, they can:
 Optimize geometry for weight and strength(Geometry is all about shapes and
their properties. )
 Select materials that meet weight, strength, and budget requirements
 Simulate part failure and identify the loading conditions that cause them
 Assess extreme environmental conditions or loads not easily tested on physical
prototypes, such as earthquake shock load
 Verify hand calculations.
 Validate the likely safety and survival of a physical prototype before testing's

14.  Utilization performance:

15.  Delay performance:

16.  Capacity performance:

17.  It is useful to understand how users of the system will
apply applications.
 Simple usage patterns can include user work times and
durations.
 Each application the total number of users.
 The frequency that a user is expected to have an
application session running.(number of sessions per
user, per day).
 How long an average application session will last(order
of minutes)
 No . of simultaneous user sessions for that application.

18.  It is useful to determine the behavior of application
sessions.
 It is used to modify performance requirements.
 To achieve a better estimate of performance levels you
will need for your network.
 Characterizing application behavior
 Data sizes that the application will be processing /
passing / communication across the network.
 Frequency and time duration for data to be passed
across the network.

19.  Traffic flow characteristics get for applications:
 Flow directions (ex: from client to server)
 Requirements for multicasting / broadcasting / unicast(walki-
talki).
(communication service)
Multicast is communication between a single sender and multiple
receivers on a network.
Broadcasting is the distribution of audio and/or video content via
any electronic mass communications medium(fm)
 Benefits of user and application behavior:
 Mission – critical(levels of importance)
 Rate – critical(transfer data rate)
 Real time(implementation)
 Interactive(how application works with user)
 High performance()

20. THANK YOU

21.  Developing RMA requirements:
 MTBCF – mission time between critical failure
 MTBF- mission time between failure
 MTTR – mean time to repair
 Uptime / downtime
 Developing DELAY requirements:
 Interaction Delay(INTD)
 Human Response Time(HRT)
 Network Propagation Delay(NPD)
 End – To – End delay
 Rountrip Delay
 Delay variations

22.  Estimates Data Rates:
 PDR – peak data rate.
 MDR – Minimum data rate.
 SDR – sustained data rate.
 Developing supplement :
 Operational suitability
 Supportability
 RMA
 Workforce