Transcript Presentation by

GAIA
VoIP traffic generator and analyzer
Presentation by
Amrut Bang
Ashish Deshpande
Vijay Gabale
Santosh Patil
Sponsored by
GS Lab Pvt. Ltd
Pune Institute of
Computer Technology
1
Agenda

Problem definition

Need/Motivation

Existing solutions & limitations

Concept of VoIP traffic generator & analyzer

Features

Overall flow

System architecture

Immediate and long term goals

References
2
Problem Definition
To develop a system, for generating &
analyzing VoIP traffic, capable of simulating
multiple hosts on a single machine to test the
performance of server applications.
3
Need

Every application requires testing before
deployment. Why?

To check the performance and the actual
handling capacity under varying loads.

A mechanism to create the practical working
conditions and analyze the target’s behavior in it.
4
A Real World Problem

Small scale companies’ requirement.

To check scalability of the system.

Costs involved for multiple machines.

Complexity of maintaining network connections.

Real need : a N/W card and a software.
5
Limitations of existing products

Commercial Applications – Costly, only for Windows.

No open source tool to simulate multiple hosts on a
single machine for VoIP.

Applications only piecemeal, targeted at the developer.

Lack well structured & scriptable UI.

No comprehensive tool to support different codecs.
6
Server
7
Server
8
Concept

Generation of VoIP traffic, simulating multiple hosts on a
single machine.

Configuring & maintaining multiple different connections.

Analyzing the performance of target server application.

Precise measurement of testing parameters.


Generating reports and displaying results graphically.
Providing scriptable UI to help an expert.
9
Abstract view of VoIP traffic generator and
analyzer
10
Working of SIP Phone
User
SIP
RTP
UDP
Kernel
IP
Ethernet
List of Clients
Client 1
………………..
Client 2
Client n
Register
Client 1
Client 2
…………………
Client n
Client 1
Client 2
…………………
Client n
Client1
Client 2
…………………
Client n
UDP
Client 1
Client 2
…………………
Client n
IP
ARP (IP Simulation)
Network
SIP
RTP
Ethernet Layer
Hardware
12
IP Simulation
172.16.0.21
Register request
ARP response
172.16.0.5
172.16.0.22
ARP broadcast
Server
172.16.0.23
Client
Client
Features

Create multiple clients and maintain
communication between them.

Generation & capture of various packets
(ARP,SIP, RTP).

Calculation of different performance parameters

Inputting load graphs

Decide No. of clients, Codec selection

Displaying server's response (Graph, Histogram,
Dial)
Demo !
15
Overall Flow
Displaying Server’s
Response
Operator
GUI
Shared Data
Packet Capture &
Analysis
Scripts
Shared Data
Target Server
Application
Packet Generation Engine
16
Client
Registration
Client State Machine
Global
Circular Buffer
Pack1
.
Pack2
.
.
.
.
Pack n
Processing
Logic
Condition
Variable
Signaling
.
N/2
.
Call Initiation
and
Communication
N/2
………..
……..
N
Receiving thread
LIBPCAP
LIBNET
Network
Hardware
17
Design Complexities

SIP stack implementation.

Efficient memory utilization.

pthread_mutex_trylock() instead of
pthread_mutex_lock().

pthread_cond_timedwait().

OS Limitations:
- Thread constraints
- Maximum number of open files permitted
GAIA Offers…

Multiple clients on a single machine.

Real traffic through simulated clients

Starting calls at different times & making
them last for different durations.

Several codec formats & silent calls.

An entire VoIP network in a single box.
Immediate Goals

Modifying libnet library to eliminate buffer copies.

Enhanced GUI and scriptable interface.

Kernel component.

Randomizing traffic generation.

Scaling up by increasing no. of clients.
20
Long Term Goals

Incorporating more protocols.

Distributed load generation.
21
References


Jung Shr Vu, Per-Yuang Wang, “The performance analysis of SIP-T
signaling system in carrier class VoIP network”, Advanced Information
Networking and Applications, ieeexplore.ieee.org
A. Pescape, S. Avallone, G. Venter,“Distributed Internet Traffic Generator
(D-ITG) Analysis & Experimentation over heterogeneous
networks,Accepted poster at ICNP,2003

Andrew Tanenbaum,”Computer Networks”,Pearson Education

Matthias Dalheimer,”Programming with Qt”, O’Reilly

Mathews,”Professional Linux Programming”

POSIX thread (pthread) library manuals

RFC 3261- SIP, RFC 1889- RTP, RFC 2327- SDP
22
Thank you !
23