DHANALAKSHMI SRINIVASAN INSTITUTE OF RESEARCH AND TECHNOLOGY-SIRUVACHUR CS6551-COMPUTER NETWORKS PART-B UNIT I 1. Discuss about ISO/OSI reference model with neat sketch Physical Datalink layer Network layer Transport layer Application layer Presentation layer Session layer 2. Explain in detail about circuit switching and datagram switching with diagram Three phases Efficiency Delay Routing Table Efficiency-RT Delay-RT 3. Explain about Cable Networks Traditional Cable networks Hybrid fibre-coaxial network Bandwidth Sharing
CM and CMTS DOCSIS 4. Explain Transmission media. Guided media Twisted pair cable Coaxial cable Fibre-optical cable Unguided media:wireless Radio waves Micro waves Infra red UNIT-II 1. Explain and detail about frame format for and Control field of HDLC Configuration and transfer modes Frames Control field 2. Discuss and detail about Standard Ethernet and Fast Ethernet Standard Ethernet MAC sublayer Physical layer IEEE standards Data link layer Physical layer
Fast Ethernet MAC sublayer Physical layer 3. What is CSMA/CD? How does it work? Distinguish between 1- Persistent and non-persistent CSMA ALOHA CSMA CSMA/CD CSMA/CA Controlled Access Reservation Polling Token Passing 4.Explain in detail about Noisy and Noiseless channel. Noiseless channel Simplest protocol Stop and wait protocol Noisy channel Stop and wait Automatic repeat request Go back N repeat request Selective repeat Automatic Repeat request Piggy backing
UNIT III 1. Briefly explain the following mechanism i)internet Protocol-IPV4,IPV6 IPV4 Address space o Notations o Classful Addressing o Classeless Addressing o NAT IPV6 Structure Address space 2.Briefly explain the following mechanism 1)Routing-Unicast, Multicast Routing Protocols UNICAST PROTOCOLS Optimization Intra and interdomain routing Distance vector routing Link state routing Path vector routing MULTICAST ROUTING Unicast,Multicast and broadcast Applications Multicast routing Routing protocols 3. Breifly explain IGMP message format and Operation. Group management
IGMP message Message Format IGMP operation Encapsulation Natstst utility UNIT IV 1. Draw the structure of TCP segment. Explain the feature of TCP TCP Service TCp feature Segment A TCP connection Flow control Error control Congestion control 2. Explain in detail about Congestion control techniques in transport layer Open loop congestion control Closed loop congestion control Examples Congestion control in TCP Congestion control in Frame Relay 3. Explain the techniques to improve QoS. Qos: Flow characteristics Flow classes Techniques to improve Qos: Scheduling Traffic Shaping Resource Reservation Admission Control
4. Explain UDP in detail. Well known ports for UDP User datagram Check sum UDP operation Use of UDP 5. Explain Procss to process delivery. Client/server paradigm Multiplexing and Demultiplexing Connectionless vs Connection Reliable vs unreliable Three protocols 1. Explain about Digital Signature Comparison Need for keys Process Services Signature schemes UNIT V 2. Explain in detail about symmetric key algorithms with neat sketch Traditional ciphers Simple modern ciphers Modern round ciphers Mode of operation 3. Describe in detail about HTTP HTTP transaction Persistent vs Non persistent connection Proxy server
4. Illustrate the operation of FTP with a neat sketch File transfer protocol Anonymous FTP 5. Describe how SMTP protocol is used in E-mail applications Architecture User agent Message transfer agent:smtp Message access agent:pop and IMAP Web based mail