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

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

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

7. The network core comprises of switches
or routers

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

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

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

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

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

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

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

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

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

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

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

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

20. Storage Area Networks (SAN)
Storage use is growing explosively
Managing 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 interconnect
Components
Servers
Storage Fabric

21. Storage Area Networks (SAN)
SAN 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 Loop

23. The Infrastructure of the Internet

24. Internet Services – World Wide Web
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

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
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
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