5. Concept of Computer Network and Network Security System

5.1 Introduction to Computer Networks and Physical Layer

• Networking Model, Protocols and Standards

• OSI Model and TCP/IP Model

• Networking Devices (Hubs, Bridges, Switches, and Routers)

• Transmission Media

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5.2 Data Link Layer

• Services, Error Detection and Corrections, Flow Control

• Data Link Protocol

• Multiple Access Protocols

• LAN Addressing and ARP (Address Resolution Protocol)

• Ethernet, IEEE 802.3 (Ethernet), 802.4 (Token Bus), 802.5 (Token Ring), PPP (Point to Point Protocol)

• CSMA/CD

• IEEE 802.3 Standard

• Wireless LANs

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5.3 Network Layer

• Addressing (Internet Address, Classful Address), Subnetting

• Routing Protocols (RIP, OSPF, BGP, Unicast and Multicast Routing Protocols)

• Routing Algorithms (Shortest Path Algorithm, Flooding, Distance Vector Routing, Link State Routing)

• Network Layer Protocols: ARP, RARP, IP, and ICMP

• IPv6 (Packet Formats, Extension Headers, Transition from IPv4 to IPv6, Multicasting)

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5.4 Transport Layer

• The Transport Service, Transport Protocols

• Port and Socket, Connection Establishment & Connection Release

• Flow Control & Buffering, Multiplexing & De-multiplexing

• Congestion Control Algorithm

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5.5 Application Layer

• Web (HTTP & HTTPS), File Transfer (FTP, PuTTY, Win SCP)

• Electronic Mail, DNS, P2P Applications

• Socket Programming, Application Server Concept

• Concept of Traffic Analyzer (MRTG, PRTG, SNMP, Packet Tracer, Wireshark)

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5.6 Network Security

• Types of Computer Security, Types of Security Attacks

• Principles of Cryptography, RSA Algorithm

• Digital Signatures, Securing E-mail (PGP)

• Securing TCP Connections (SSL), Network Layer Security (IPsec, VPN)

• Securing Wireless LANs (WEP), Firewalls