Exam 2 Review

Networking

CS 3470, Section 1

Sarah Diesburg

Switching and Bridging

Definitions Circuit switching

Also connection-oriented approach Packet switching

Also connectionless/datagram approach Asymmetric routing Hub Bridge

Switching and Bridging

Definitions Flooding (with switches) Root bridge (spanning tree protocol) VLAN

Switching and Bridging

Short answer Bridge advantages over hubs Bridge self-learning algorithm Need for spanning tree algorithm Be able to construct the spanning tree by

looking at a network diagram Don’t have to be able to write out all the

configuration messages

Routers

Definitions Router Gateway Queueing delay Switching fabrics

Routers

Short answers Types of switching fabrics

Memory, bus, crossbar Routers compared to switches Four basic components to a router

architecture Input ports, output ports, switching fabric,

routing processor

Forwarding

Definitions Forwarding table Virtual Circuit Identifier (VCI) Permanent Virtual Circuit Switched Virtual Circuit

Forwarding

Short answers Identifying full host-to-host virtual circuit

connections Constructing datagram forwarding tables

Internet Protocol (IP)

Definitions Internetwork IP packet delivery model

Connectionless, best-effort Maximum Transmission Unit (MTU)

Internet Protocol (IP)

Short answer Be able to explain certain IP packet

format fields Version, Ident, TTL, Checksum

Be able to compare and contrast the transport-level protocols that run on top of IP TCP, UDP

Addressing

Definitions Mulit-homed host Classful addressing scheme Classless Inter-Domain Routing (CIDR) Broadcast address Loopback address Network Address Translation (NAT) Subnet mask, subnet ID Longest-prefix match

Addressing

Short answers Be able to explain number of network/host bits

that make up a class A, B, C network Be able to explain the reason for the ARP and

DHCP protocols Be able to determine the destination subnet of a

packet (Homework 6)

Routing

Definitions Autonomous System (AS) Intra-AS Routing Inter-AS Routing Link-state routing Distance-vector routing

RIP is example Count-to-infinity problem Split horizon with poison reverse

Routing

Short answers What is the difference between routing

and forwarding? Dijkstra’s algorithm (Homework 7)

Inter-AS Routing and IPv6

Definitions Open Shortest Path First (OSPF)

Type of link-state routing algorithm Border Gateway Protocol (BGP) Different types of ASs

Stub AS, Multihomed AS, Transit AS

Inter-AS Routing and IPv6

Short answers What are some of the reasons we are trying

to move to IPv6? How large is an IPv6 address? What does the :: mean in an IPv6 address? How can we go from an IPv4 address to an

IPv6 address? How can we go from an Ethernet MAC

address to an IPv6 address?

Network Programming

Short answers Control flow of chat

Server side and client side Creating your own protocols by sending

specialized data across your packet For example, our chat programs expected a

certain struct chat_packet with specific members

Network Programming

Short answers Importance of network-to-host order and

host-to-network order functions htons() and ntohs()

What is the default network order? Little-endian or big-endian?