tailieunhanh - A Tutorial on Network Security: Attacks and Controls

For each extracted TCP connection, we record the sequence of size, arrival time tuples for each packet in the connection, in arrival order. We encode the packet’s direction in the sign bit of the packet’s size, so that packets sent from server to client have size less than zero and those from client to server have size greater than zero. Since the traces in this data set consist mostly of unencrypted, non-tunneled TCP connections, a few additional preprocessing steps are necessary to simulate the more challenging scenarios which our techniques are designed to address. To simulate the effect of encryption on the traffic in our data. | A Tutorial on Network Security Attacks and Controls Natarajan Meghanathan Assistant Professor of Computer Science Jackson State University Jackson MS 39217 UsA Phone 1-601-979-3661 Fax 1-601-979-2478 E-mail Abstract With the phenomenal growth in the Internet network security has become an integral part of computer and information security. In order to come up with measures that make networks more secure it is important to learn about the vulnerabilities that could exist in a computer network and then have an understanding of the typical attacks that have been carried out in such networks. The first half of this paper will expose the readers to the classical network attacks that have exploited the typical vulnerabilities of computer networks in the past and solutions that have been adopted since then to prevent or reduce the chances of some of these attacks. The second half of the paper will expose the readers to the different network security controls including the network architecture protocols standards and software hardware tools that have been adopted in modern day computer networks. 1. Introduction to Computer Networks With the phenomenal growth in the Internet network security has become an integral part of computer and information security. Network security comprises of the measures adopted to protect the resources and integrity of a computer network. This section reviews the basics of computer networks and Internet in order to lay a strong foundation for the reader to understand the rest of this paper on network security. ISO-OSI Reference Model The communication problem in computer networks can be defined as the task of transferring data entered by an application user in one system to an application user in another system through one or more intermediate networks 1 . The communication problem is solved using a layered approach through a collection of protocols forming the so-called protocol suite. Each layer dealing with