IS 410 chapter 5

3 types of fundamental approaches to routing

1. centralized routing 2. static routing 3, dynamic routing

3 ways a network manger can connect to a router and configure and maintain it.

1. console port 2. network interface port 3. auxiliary port

Router has 3 main functions (3)

1. it determines a path for a packet to travel over 2. transmit the packet across the path 3. it supports communication between wide variety of devices and protocols

dynamic routing 2 drawbacks

1. it requires more processing by each computer or router in the network 2. the transmission of routing information "wastes" network capacity

transport layer - layer 4 performs 3 functions

1. linking the application layer to the network 2. session management ( breaking long messages into smaller packets for transmission) 3. segmenting management ( establishing an end-to-end connection between sender and receiver)

network layer - layer 2 performs 2 functions

1. routing ( determining the next computer to which the message should be sent to reach the final destination) 2. addressing ( finding the address to the next computer)

Access Control List (ACL)

ACL defines what types of packets should be routed and what types of packets should be discarded

Interior Gateway Routing Protocol (IGRP)

EIGCP records information about a route's transmission capacity, delay, reliability, and loan

segment

Protocol Data Unit (PDU) at the transport layer

Border Gateway Protocol (BGP)

a dynamic distance vector exterior routing protocol used on the Internet to exchange routing information between autonomous systems- that is sections of the internet

Enhanced Interior Gateway Routing Protocol (EIGRP)

a dynamic hybrid interior routing protocol developed by Cisco and is commonly used inside the organizations. Hybrid means that is has some features that act like distance vector protocols, and some other features that act like link-state protocols

dynamic addressing

a server is designated to supply a network layer address to a computer each time the computer connects to the network

centralized routing

all routing decisions are made by one central computer to router

auxiliary port

allows an admin to log in via a direct, non-network connection

Resource Reservation Protocol (RSVP) and Real-Time Streaming (RTSP)

both permit application layer software to request connections that have certain minimum data transferring capabilities. RTSP: geared toward audio/video streaming application RSVP: more general purpose

session

can be thought of as a conversation between two computers

link state dynamic routing

computers or routers track the number of hops in the route, the speed of the circuits in each route, and how busy each route is.

Routing Information Protocol (RIP)

dynamic distance vector interior routing protocol that is commonly used in smaller networks, such as those operated by one organization

connectionless messaging

each packet is treated separately and makes its own way through the network when connection-oriented messaging is desired TCP is used

Address Resolution Protocol (ARP)

in the subnet when a broadcast message is send in the LAN the message is a specially formatted request using ARP. "Whoever is IP address xxx.xxx.xxx.xxx. please send me your data link layer address. The software in the computer with the address sends an ARP response with its data layer address.

Open Shortest Path First (OSPF)

is a dynamic hybrid interior protocol that is commonly used on the internet is preferred interior routing protocol used by TCP/IP

Intermediate System to Intermediate System (IS-IS)

is a link state interior routing protocol that is commonly used in large networks

routing protocol

is a protocol that us used to exchange information among computers to enable them to build and maintain their routing tables

static routing

is decentralized, which means that all computers or routers in the network make their own routing decisions following a formal protocol with static routing, routing decisions are made in a fixed manner by individual computers or routers static routing is commonly used in networks that have few routing options that seldom change

autonomous system

is simply a network operated by one organization such as IBM or Indiana University

Internet Control Message Protocol (ICMP)

is the simplest interior routing protocol on the internet. ICMP is simply an error-reporting protocol that enables computers to report routing errors to messages senders

multicast message

is used to send the name message to a group of computers

segmenting

means to take one outgoing message from the application layer and break it into a set of smaller segments for transmission through the network

ICANN - Internet Corporation for Assigned Names and Numbers

no one is permitted to operate a computer on the internet unless they use approved addresses. ICANN is responsible for managing the assignment of network layer addresses and application layer addresses.

Real-Time Transport Protocol (RTP)

once the connection has been established they use RTP to send packets across the connection

Unicast message

one computer sends a message to another computer

exterior routing protocols

protocols used between autonomous systems

Anatomy of routers

routers are essentially special-purpose computers that consist of a CPU, memory, and ports or interfaces that connect to them to the network and/or other devices so that a network admin can communicate with them

distance vector dynamic routing

routers count the number of hops along a route a hop is one circuit

dynamic routing (adaptive routing)

routing decisions are made in a decentralized manner by individual computers. This approach is used when there are multiple routes through a network, and it is important to select the best route.

Routers

routing done by special devices called routers. Routers are usually found at the edge of subnets because they are the devices that connect subnets together and enable messages to flow one subnet to another as the messages move through the network from sender to receiver

Quality of Service (QoS)

routing is a special type of connection-oriented messaging in which different connections are assigned different priorities

User Datagram Protocol (UDP)

second transport layer of TCP/IP. UDP is used when the sender needs to send a single small packet to the receiver used when connectionless messaging is desired

Server Name Resolution

server name resolution is the translation of application layer address into network layer addresses

Connection-Oriented Messaging

sets up a TCP connection (a session) between the sender and receiver. 3 way handshake occurs here

Subnets

the first part of the address defines the network, and the second part of the address defines a particular computer or host on the network subnet works or subnets are designed on the network that subdivide the network into logical pieces

Dynamic Host Configuration Protocol (DHCP)

the most common standard for dynamic addressing. DCHP does not provide a network layer address in a configuration file. Instead, there is a special software package installed on the client that instructs it to contact a DHCP server to obtain an address

Routing

the process of determining the route or path through the network that a massage will travel from sending computer to the receiving computer

interior routing protocol

the routing protocol used inside an autonomous system

Domain Name Server (DNS)

throughout the Internet a series of computers called name servers provides DNS servers. These name servers have address databases that store thousands of Internet addresses and their corresponding IP address. ex: directory assistance

address resolution

to send a message, the sender must be able t translate the application layer address ( or server name) of the destination into a network layer address and int turn translate that into a data link layer address.

network layer address

used by the network layer. The network layer protocol used on the Internet is IP, so this Web Address (www.indiana.edu) is translated into an IP address that is 4 bytes long when using IPv4 (eg. 129.79.127.4)

TCP linking to the application layer

with TCP/IP each application layer software package has a unique port address. when application layer sending message it must tell TCP software its own port address ( source address) and the port address of the destination computer (destination port address)