Networking and Security Issues in Digital Library Dr. R. Radhakrishna Pillai IIM Kozhikode
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.
Networking Components • Hosts (end Systems) • Server • Packet Switch/Router • Modem • Mobile • Base Station • Satellite link
Networking Protocol • The rule for exchanging information between two computers
End-to-end Communication • The communication always takes place between two end systems (hosts)
Network Core • The network core comprises of switches • or routers
Circuit Switching • In Circuit Switching the network resources (e.g., capacity/bandwidth) are reserved for communication
Circuit Switching • In Circuit Switching the network resources (e.g., capacity/bandwidth) are reserved for communication
Packet Switching • In Packet Switching the network resources (e.g., capacity/bandwidth) are NOT reserved for communication. Packets between various hosts share common resources
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)
Access Networks • Access networks connect the end-systems to the core network. Different technologies are used for access
Access Networks • Access networks connect the end-systems to the core network. Different technologies are used for access (e.g. Hybrid fiber-coaxial access)
Access Networks • Access networks connect the end-systems to the core network. Different technologies are used for access (e.g. Home Network)
Delays in Networks • Various components of packet delay include • Nodal processing delay • Queueing delay • Transmission delay • Propagation delay
Delays in Networks • Dependence of Queueing delay on traffic intensity
Delays in Networks • Smaller sized packets result in smaller end-to-end delays
Protocol Stack • Layers of functions with standardised interface between them
Protocol Stack • Layers of functions with standardised interface between them
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
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.
Fibre Channel Technologies • Arbitrated Loop
The Infrastructure of the Internet
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
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?
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
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
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
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
Operational Characteristics of Internet • Internetworking technologies are based on open standards • Internetworking technologies operate asynchronously • Internet communications have inherent latency • Naturally decentralised • Scalable
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
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.
Securing Infrastructure against Malicious Threats • Threats: • External attacks – DoS attacks, DDoS, Spoofing • Intrusion • Viruses and Worms
DoS/DDoS • Easy to execute, difficult to defend against • Abrupt termination of conversation • Attack from different sites – monitoring difficult • Degradation of service attack
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
Viruses and Worms • Replicate and spread themselves (worms) • Virus needs assistance to replicate • The Code Red Worm (2001)
Securing Infrastructure against Malicious Threats • Defensive Measures • Security Policies • Firewalls • Authentication • Encryption • Patching and Change management • Intrusion detection and network monitoring
Securing Infrastructure against Malicious Threats A HOLISTIC APPROACH IS THE NEED OF THE DAY
Thank You
