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Agendas. Chapter 3 (Recap) Understanding Internetworking Infrastructure (Chapter 5) Case 2-2: The iPremier Company (A): Denial of Service Attack. Three Inter-organizational Governance Models (Recap). What are the three governance models? Describe each governance model.
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Agendas • Chapter 3 (Recap) • Understanding Internetworking Infrastructure (Chapter 5) • Case 2-2: The iPremier Company (A): Denial of Service Attack
Three Inter-organizational Governance Models (Recap) • What are the three governance models? • Describe each governance model.
Three Inter-organizational Governance Models • Market • Simple exchange of goods, services, and payments, usually during a specific time period and with limited interaction or information sharing between the parties involved • Hierarchy • Formal contracts and authority define the activities to be performed, the products or services to be provided, the price to be paid by each party, and the length of the relationship • Partnership • Require shared goals, complementary expertise and skills, high levels of trust among the parties, and networked integration of processes and work across organizational boundaries
Three Network Ownerships • What are the three types of ownerships? • Describe each network ownership.
Three Network Ownerships (Recap) • The majority of specialized units may be located inside a corporation or other legally defined organization. • An alliance may be formed between two ( or a small number of players). • A diverse community, also called an ecosystem, of players representing different roles (e.g., suppliers, distributors, buyers) may work together to achieve shared goals.
Governance and Ownership Ownership
Chapter 5: Understanding Internetworking Infrastructure • Technical issues vs. business issues • Bridging the gap between the business and technical domains
Chapter 5: Understanding Internetworking Infrastructure Corporate Telecommunications System
Chapter 5: Understanding Internetworking Infrastructure Moore’s Law
Chapter 5: Understanding Internetworking Infrastructure TCP/IP Evolution of Corporate IT Infrastructure
Chapter 5: Understanding Internetworking Infrastructure Metcalfe’s Law
Chapter 5: Understanding Internetworking Infrastructure Bandwidth Explosion
Components of Internetworking Infrastructure A Simple LAN
Network Elements – LAN • Local Area Networks (LAN) • Connects computers and other digital devices within 2000 ft radius • Cabling or wireless technology links computers, network interface cards, and software • Network Operating System (NOS) • Network Topologies • Star, bus, and ring topologies
Network Elements – LAN LAN Topologies
Network Elements – WAN Wide Area Networks (WAN) • Span broad geographic distances • Can consist of combination of: • Switched lines • Dedicated lines • Microwave • Satellite communications • Private WANs expensive to support
Network Elements – WAN An Example of WAN
Network Elements – MAN • Metropolitan Area Network (MAN) • Scope between LAN and WAN • Limited distance; faster and less expensive than WAN • Value-Added Networks • Private, third-party managed, data only networks • Subscription basis
Network Elements – Bridge (Switch), Router, Firewall, Caching Bridge (Switch) • Connect network segments at the physical layer • Relay and subdividing network device • Less or no intelligent in transporting data Router • A network device containing software and hardware – usually tailored to the tasks of routing and forwarding information.
Network Elements – Bridge (Bridge, Router, Firewall, Cache) Firewall • A firewall is a dedicated hardware, or software running on another computer, which inspects network traffic passing through it, and denies or permits passage based on a set of rules. Cache • A cache is a block of memory for temporary storage of data likely to be used again. The CPU and hard drive frequently use a cache, as do web browsers and web servers.
Elements of Processing Systems • Client Devices and Systems • Server Devices and Systems • Mainframe Devices and Systems • Middleware • Middleware is the enabling technology of enterprise application integration. It describes a piece of software that connects two or more software applications, allowing them to exchange data. • TCP/IP • Extremely important • Not well-understood
Client/Server Computing • Client/server computing: Splits processing between “clients” and “servers” on network • Powerful personal computers connect to network with one or more server computers • Has extended networking to parts of business that could not be served by centralized architecture • Processing load balanced over many smaller machines
Client/Server Computing (n-tier) Remote method innovation/Internet Inter-Orb Protocol
Packet Switching (How Internet Work) • Messages broken into “packets” before transmission • Packets include destination and error-checking information • Packets travel independently using routers; reassembled into original message at destination
Transmission Control Protocol/Internet Protocol (TCP/IP) • Open suite of protocols for connectivity developed in 1970s • Provides standards for breaking messages into packets, routing them to destination addresses, and reassembling them at end • Allows for communication regardless of hardware/software
Transmission Control Protocol/Internet Protocol (TCP/IP) TCP/IP: Four-Layer Reference Model • Network interface layer: Placing packets on and receiving them from network medium • Internet layer: Addressing, routing, packaging data packets • Transport layer: Acknowledging and sequencing packets to/from application • Application layer: Communication between applications and other layers
Complexity and Coupling • Complexity • Systems have many interactions • Interactions can be linear (simple) or complex • Linear cause and effect relationships are clear • Complex cause and effect relationships are difficult to see or anticipate • Coupling • Here coupling or dependency is the degree to which each network system relies on each other. • Coupling in systems can be tight or loose. • Tight coupling changes in A seriously affect B
Why Systems Are Vulnerable? Telecommunications networks vulnerabilities
Why Systems Are Vulnerable? Type of computer crimes and criminals • Hacker: An outside person who has penetrated a computer system, usually with no criminal intent. • Cracker: A malicious hacker. • Social engineering: Getting around security systems by tricking computer users into revealing sensitive information or gaining unauthorized access privileges. • Cybercrimes: Illegal activities executed on the Internet. • Identify theft: A criminal (the identity thief) poses as someone else. • Cyberwar: War in which a country’s information systems could be paralyzed from a massive attack by destructive software. • Virus: Software that can attach itself to (“infect”) other computer programs without the owner of the program being aware of the infection.
IS Security and Control Security Treats
Protecting the Digital Firm • Firewall screening technologies • Static packet filtering • Network address translation • Application proxy filtering • Intrusion detection systems • Scanning software • Monitoring software
Security and Electronic Commerce • Encryption • Authentication • Message integrity • Digital signatures • Digital certificates • Public key infrastructure (PKI)