IACSIT International Journal of Engineering and Technology, Vol.2, No.2, April 2010
ISSN: 1793-8236
Abstract— Botnet is most widespread and occurs commonly
in today‘s cyber attacks, resulting in serious threats to our
network assets and organization’s properties. Botnets are
collections of compromised computers (Bots) which are
remotely controlled by its originator (BotMaster) under a
common Command-and-Control (C&C) infrastructure. They
are used to distribute commands to Bots for malicious activities
such as distributed denial-of-service (DDoS) attacks, spam and
phishing. Most of the existing botnet detection approaches
concentrate only on particular botnet command and control
(C&C) protocols (e.g., IRC,HTTP) and structures (e.g.,
centralized), and can become ineffective as botnets change their
structure and C&C techniques. In this paper we proposed a
new detection framework which focuses on P2P based botnets.
This proposed framework is based on our definition of botnets.
We define a botnet as a group of bots that will perform similar
communication and malicious activity patterns within the same
botnet. In our proposed detection framework, we monitor the
group of hosts that show similar communication pattern in one
stage and also performing malicious activities in another step,
and finding common hosts on them.
Index Terms— botnet; bot; centralized; decentralized; P2P;
detection
I. INTRODUCTION
Nowadays, the most serious manifestation of advanced
malware is Botnet. Botnets are networks consisting of large
number of Bots. Botnets are created by the BotMaster to
setup a private communication infrastructure which can be
used for malicious activities such as Distributed
Denial-of-Service( DDoS), sending large amount of SPAM
or phishing mails, and other nefarious purpose [ 1,2,3,4,5 ] .
There are many ways which attackers use to infect a
computer in the Internet with Bot include sending email and
using malicious websites, but the most common way is
searching the Internet to look for vulnerable and unprotected
computers [6.].
The main difference between Botnet and other kind of
malwares is the existence of Command-and-Control (C&C)
infrastructure. The first generation of Botnets utilized the
Manuscript received March 9, 2010.
Hossein Rouhani Zeidanloo, Rabiah Bt Ahmad and Saman Shojae
Chaeikar, centre for Advanced Software Engineering, Universiti Teknologi
Malaysia, Kuala Lumpur, Malaysia (email:h_rouhani@hotmail.com,
rabiah@citycampus.utm.my, saman_shoja@yahoo.com).
Azizah Bt Abdul Manaf, college of Science and Technology, Universiti
Teknologi Malaysia, Kuala Lumpur, Malaysia (email:
azizah07@citycampus.utm.my).
Mazdak Zamani, faculty of Computer Science and Information System,
Universiti Teknologi Malaysia, Kuala Lumpur, Malaysia (email:
zmazdak2@siswa.utm.my).
IRC (Internet Relay Chat) channels as their
Common-and-Control (C&C) centers. The centralized C&C
mechanism of such Botnet has made them vulnerable to
being detected and disabled. Therefore, new generation of
Botnet which can hide their C&C communication have
emerged, Peer-to-Peer (P2P) based Botnets. The P2P Botnets
do not suffer from a single point of failure, because they do
not have centralized C&C servers [12]. Attackers have
accordingly developed a range of strategies and techniques to
protect their C&C infrastructure. The rest of the paper is
organized as follows. In Section 2, we analyze different
botnet topologies and completely consider the protocols that
are currently being used in each model. In Section 3, we
review the related work. In Section 4, we describe our
proposed detection framework and all its components and
finally conclude in section 5.
II. BOTNET TOPOLOGIES
According to the Command-and-Control(C&C) channel,
we categorized Botnet topologies into two different models,
the Centralized model and the Decentralized model.
A. Centralized model
The oldest type of topology is the centralized model. In
this model, one central point is responsible for exchanging
commands and data between the BotMaster and Bots. Many
well-known Bots, such as AgoBot, SDBot, Zotob and RBot
used this model. In this model, BotMaster chooses a host
(usually high bandwidth computer) to be the central point
(Command-and-Control) server of all the Bots. The C&C
server runs certain network services such as IRC or HTTP.
The main advantage of this model is small message latency
which cause BotMaster easily arranges Botnet and launch
attacks. Since all connections happen through the C&C
server, therefore, the C&C is a critical point in this model. In
other words, C&C server is the weak point in this model. If
somebody manages to discover and eliminates the C&C
server, the entire Botnet will be worthless and ineffective.
Thus, it becomes the main drawback of this model.
Since IRC and HTTP are two common protocols that C&C
server uses for communication, we consider Botnets in this
model based on IRC and HTTP. Figure 1 shows the basic
communication architecture for a Centralized model.
A Proposed Framework for P2P Botnet Detection
Hossein Rouhani Zeidanloo, Azizah Bt Abdul Manaf, Rabiah Bt Ahmad, Mazdak Zamani,
Saman Shojae Chaeikar