Telecommunication Network Security

2015

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34 pages

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collaborative visualization where very high-end video transfers are used in oil exploration, or designing automobiles, etc. Further details of ITU-T security guidelines, other related matters are in [6]. 3. The Context of Security and the Threat-Scape in Cyber Warfare The bulk of this segment of the chapter and what follows it to the end of the chapter is taken from an ongoing research work at the School of Engineering, Design and Technology, University of Bradford.[7] It will cover security concepts, security engineering in context, a brief overview of cryptology(cryptography, cryptanalysis), social engineering, Distributed Denial of Service (DDoS) attack, IP Trace-back mechanism and the threat-scape in cyber warfare. This segment will be closed with some deductions.

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Figure 1. Ubiquity of Internet as an Indispensable ICT Infrastructural Facility. bandwidth. Intervening distance also brings attention to the need for a system that is attenuation effective, less cumbersome, relatively immune from interference and electromagnetic noise, secure and provides room for upgrading with as little economic and technical costs as possible. [3] This chapter is primarily concerned with the security aspect of telecommunication systems. In this chapter, unless otherwise specified, whenever the term communication(s) is used, it equally denotes telecommunication(s) as explained earlier. Similarly, since the entire ICT world is mostly computerised, the focus will be on computer-mediated communications and cyber-space.

In modern context, telecommunications refers to any technology, service, system, or other resource that provides or ensures transmission of electronic data and information. Telecommunication resources may be voice and data networks, wireless services, high speed data communications, telephones, network servers, switches, or any other device, service or system used in electronic communication transmissions. The location/nature of telecommunication systems is equally diverse: ranging from local or building networks to global networks; from single telephone handsets to communication satellites; and whether dedicated to a specific application or shared by many users, programs, and applications. [4]

Figure 3. Security Engineering Analysis Framework. trick is to design security systems that maximize the positive aspects of people, whil minimizing their negative aspects.[14]

Figure 4. The Science of Secret Writing and its Main Branches.

For symmetric cryptography, the key, which is kept secret, is known only to the sender and receiver. Thus, for ‘n’ users, the number of keys required is: [20]

Figure 6. A Sample DDoS Attack from a Botnet. The threat is obvious, since most of the thousands of botnets that have been observed on the Internet are at least of this size; many prominent botnets like Storm and Conficker have several million bots. Thus, the national infrastructure faces a severe threat.

As illustrated in Figure 7, in the IP trace-back mechanism, the user (victim) at a linked terminal unit first issues a tracking request for a packet that is considered to be an attack. A piece of packet data is encoded with a unidirectional hash function and transferred to a trace- back system within an Autonomous System (AS) to which the user belongs. The requested trace-back system examines each packet to determine whether it is coming in from an external source or from its own system. When the issued packet is coming from a neighbouring AS, a trace request is queried to the AS. This process is repeated recursively until the trace-back system identifies an actual AS to which the attack source belongs.[34] Although practical tests have demonstrated that tracing the original source of Internet communications is feasible, there are still loose ends to be tied up before the technology becomes a market reality.[34] Figure 7. Mechanism of IP Trace-back Technology.

Figure 8. Cryptographic Settings for Secret-key, Public-key, and Hash Function (a, b and c respectively) at ensuring confidentiality, integrity, availability and authenticity, as discussed herein.[32] As people started figuring out ways of encoding information or trying to understand others’ encoded messages, the field kept on developing until it reached complexity; and the development continues.[10] The common technica been identified in the course of this development relate to the threa the current level of problems that have s of eavesdropping, modification, replay, masquerading (impersonation, identity theft), penetration anc repudiation, as well as their highly sophisticated techniques of accomplishment. From inception, cryptography has been struggling to find solutions to t hese problems. The cryptographic countermeasures designed to meet these challenges includ e mechanisms aimed at ensuring confidentiality, integrity, availability and authenticity, as discussed herein.[32] 4.3.1. Confidentiality

Figure 9. The Need for Time Authentication. Most text and data messages are not real-time communication, thus they require | different method of authentication called the Message Authentication Code (MAC). This i illustrated in Figure 10. The MAC is similar to a hash function. However, while a virus cai be used to modify a hash function, the MAC cannot be modified in the same way, because i relies on a key that is known only to the users.[32] Authentication using encryption witl symmetric algorithm has its limitations, but the application of asymmetric encryption usin; the RSA algorithm guarantees the authenticity of the message. This is because if an encrypte document can be decrypted by a public key, it implies that the message must have beet encrypted with the private key pair. This is discussed further in Section 4.3.5. The MAC i encrypted using the secret key and the result is attached to the message that is sent to th receiver. At the receiver the encrypted MAC header is removed from the message anc decrypted using the secret key. The resulting calculation is then compared with the origina plain MAC value from the message. If the two quantities are the same, this verifies th integrity and authenticity of the message.

Figure 10. The Message Authentication Code Process (Courtesy: Sutton, R.J., 2002). The primary purpose of the digital signature is just to check for message integrity. It is not used to encrypt the message, thus, it does not offer confidentiality.

Figure 11. Generation of a Message Signature Using the Author’s Private Key. (Courtesy: Sutton, R.J., 2002).

Telecommunication Network Security Figure 12. Receiver Runs Verification Algorithm to Detect Modifications to the Message. (Courtesy: Sutton, R.J., 2002).

As a result of the ubiquity of wireless communication systems, culminating in the global Internet, modern technology dictates that reliable means for explicit identification be put in place between/among interacting entities. The process of user identification is generally called authentication. To ‘authenticate’ is to establish the validity of the claim of a user or an entity. In the cyber world, it means positive verification of a user, device, or other entity in a computer system, often as a prerequisite for granting access to resources in a system. Authentication is among the three processes of AAA (Authentication, Authorization and Accounting), [61, 62, 64] as illustrated in Figure 13. When a user requests for access to the restricted area, he is first authenticated, based on which access is granted or denied. Where access is granted, the controller establishes connection between the user and the restricted area; whether access is granted or not, an account which records the information concerning the user’s actions is created. [62] Authentication techniques are divided into four main categories, based on related authentication factors. These respectively employ the following: [65] what you (user) know - this is based on knowledge of confidential information (e.g. password); what you have - techniques using tokens, smart cards, RFID (Radio Frequency Identification Device), hardware keys, etc.; what (or who) you are — these deal with biometric techniques that are limited to a human authentication, using parameters like the eyes, fingerprints, etc.; and where you are — this technique is based on the user’s physical location; it is a new authentication factor. [63, 65] Authentication techniques are divided into four main categories, based on related