2. Networking and Security Issues in Digital Library Dr. R. Radhakrishna Pillai IIM Kozhikode

3. What is the Internet? The largest computer network in the world (a network of networks) Information exchange is seamless using open, non- proprietary standards and protocols, within interconnected networks Spirit of information sharing and open access underlies the Internet.

4. Hosts (end Systems) Server Packet Switch/Router Modem Mobile Base Station Satellite link Networking Components

5. The rule for exchanging information between two computers Networking Protocol

6. The communication always takes place between two end systems (hosts) End-to-end Communication

7. The network core comprises of switches or routers Network Core

8. In Circuit Switching the network resources (e.g., capacity/bandwidth) are reserved for communication Circuit Switching

9. In Circuit Switching the network resources (e.g., capacity/bandwidth) are reserved for communication Circuit Switching

10. In Packet Switching the network resources (e.g., capacity/bandwidth) are NOT reserved for communication. Packets between various hosts share common resources Packet Switching

11. Packet switched networks have “Efficient” utilization of resources (e.g. The Internet) compared to circuit switched networks (e.g., The Telephone Network) Classification of Networks

12. Access networks connect the end-systems to the core network. Different technologies are used for access Access Networks

13. Access networks connect the end-systems to the core network. Different technologies are used for access (e.g. Hybrid fiber- coaxial access) Access Networks

14. Access networks connect the end-systems to the core network. Different technologies are used for access (e.g. Home Network) Access Networks

15. Various components of packet delay include –Nodal processing delay –Queueing delay –Transmission delay –Propagation delay Delays in Networks

16. Dependence of Queueing delay on traffic intensity Delays in Networks

17. Smaller sized packets result in smaller end-to-end delays Delays in Networks

18. Layers of functions with standardised interface between them Protocol Stack

19. Layers of functions with standardised interface between them Protocol Stack

20. Storage Area Networks (SAN) Storage use is growing explosivelyStorage use is growing explosively Managing locally attached storage is difficultManaging locally attached storage is difficult –Backup –Access by multiple servers Combines the best of storage and networking technologies to provide low latency, high bandwidth, high availability interconnectCombines the best of storage and networking technologies to provide low latency, high bandwidth, high availability interconnect ComponentsComponents –Servers –Storage Fabric

21. Storage Area Networks (SAN) SAN enables storage resources and server resources to grow independentlySAN enables storage resources and server resources to grow independently Storage on a given server can be increased or decreased as needed without complex reconfiguring or re-cabling of devices. Enforcing security policies for access rights to a given device is a core part of the infrastructure Data can be transferred directly from device to device without server intervention The primary technology used in storage area networks today is Fibre Channel.

22. Fibre Channel Technologies Arbitrated LoopArbitrated Loop

23. The Infrastructure of the Internet

24. An application that uses the Internet transport functions A system with universally accepted standards for storing, retrieving, formatting, and displaying information via a client/server architecture Based on HTML - standard hypertext language used in Web Handles text, hypermedia, graphics, and sound Internet Services – World Wide Web

25. Internet Challenges Internet Regulation –Technical organizations (e.g., World Wide Web Consortium) develop standards governing the Internet’s functionality –These organizations are not formally charged in any legal or operational sense with responsibility for the Internet –How to control controversial content on the Web?

26. Internet Challenges (continued) Internet Expansion –Tremendous Internet traffic growth has strained some elements of the network Slower retrieval times Unreliable data transmission Denial of service by overloaded servers –Approaches to overcoming this congestion include Improved hardware technology Improved Web management software

27. Internet Challenges (continued) Internet Privacy - Web sites collect information with and without consumers’ knowledge –Cookie - small data file placed on users’ hard drives when a site is first visited. Collects data on pages visited and content viewed. –Three potential approaches to the privacy issue Government lets groups develop voluntary privacy standards; does not take any action now unless real problems arise Government recommends privacy standards for the Internet; does not pass laws at this time Government passes laws now for how personal information can be collected and used on the Internet –Financial transaction security also a concern

28. Intranets A private network that uses Internet software and TCP/IP protocols –Provide employees with easy access to corporate information –Used to deploy corporate applications Examples – policies and procedures manuals; human resource forms; product catalogs –Security is a concern Security measures include – public key security, encryption, digital certificates, firewalls

29. Extranets An extension of an intranet to selected outside business partners, such as suppliers, distributors, and key customers –Provide business partners with easy access to corporate information and easy collaboration Security –Critical to prevent unwanted entry into internal systems –Virtual private networks (VPNs) are often used to add security to Internet communication

30. Operational Characteristics of Internet Internetworking technologies are based on open standards Internetworking technologies operate asynchronously Internet communications have inherent latency Naturally decentralised Scalable

31. The rise of Internetworking: Business Implications Network becomes a computer Quicker realization of economic value Emergence of real-time infrastructure: Better data better decisions, improved process visibility, Improved process efficiency, From make-to-sell to sense-and-respond Broader exposure to operational threats New models of service delivery Managing legacies

32. Future Internet Initiatives Internet2 –A collaboration among more than 180 U.S. universities to develop leading-edge networking and advanced applications for learning and research. –A group of very high bandwidth networks on the Internet. –Partnership between universities, industry, and government. Next Generation Internet (NGI) –Federal government led initiative to advance Internet technology and applications.

33. Securing Infrastructure against Malicious Threats Threats: –External attacks – DoS attacks, DDoS, Spoofing –Intrusion –Viruses and Worms

34. DoS/DDoS Easy to execute, difficult to defend against Abrupt termination of conversation Attack from different sites – monitoring difficult Degradation of service attack

38. Intrusion Get access to company’s internal IT infrastructure –User name, password –Sniffer software –Vulnerabilities left in the software Difficult to figure out what intruders might have done inside

39. Viruses and Worms Replicate and spread themselves (worms) Virus needs assistance to replicate The Code Red Worm (2001)

40. Securing Infrastructure against Malicious Threats Defensive Measures –Security Policies –Firewalls –Authentication –Encryption –Patching and Change management –Intrusion detection and network monitoring

41. Securing Infrastructure against Malicious Threats A HOLISTIC APPROACH IS THE NEED OF THE DAY

42. Thank You