examining tcp/ip. overview introduction to tcp/ip tcp/ip protocol suite name resolution examining...

Examining TCP/IP

Overview

Introduction to TCP/IP

TCP/IP Protocol Suite

Name Resolution

Examining the Data Transfer Process

Routing Data


The Communication Process

TCP/IP Layers

Identifying Applications

The Communication Process

NameAddress

Post OfficePost Office Post OfficePost Office

NameAddressNameAddress

Post OfficePost Office Post OfficePost Office

NameAddress

TCP/IP Layers

Application LayerApplication Layer

Transport LayerTransport LayerTransport LayerTransport Layer

Internet LayerInternet LayerInternet LayerInternet Layer

Network Interface LayerNetwork Interface LayerNetwork Interface LayerNetwork Interface Layer

Internet LayerIPIP ICMPICMP IGMPIGMP ARPARP

Network Interface Layer

EthernetEthernetATMATM

Transport LayerUDPUDPTCPTCP

Application Layer

FTPFTPHTTPHTTP

Identifying Applications

UDPUDPTCPTCP

FTPFTPHTTPHTTP

192.168.2.150192.168.2.150

FTP Server

HTTP Server

TCP Port 20, 21TCP Port 20, 21

TCP Port 80TCP Port 80

IP Address + TCP Port or UDP Port= Socket


Transmission Control Protocol (TCP)

User Datagram Protocol (UDP)

Internet Protocol (IP)

Internet Control Message Protocol (ICMP)

Internet Group Management Protocol (IGMP)

Address Resolution Protocol (ARP)

TCP/IP Utilities

Transmission Control Protocol (TCP)

IP ICMP IGMP ARP

UDPTCPTCP

User Datagram Protocol (UDP)

UDPUDPTCP

IP ICMP IGMP ARP

Internet Protocol (IP)

RouterRouterUDPTCP

IPIP ICMP IGMP ARP

Internet Control Message Protocol (ICMP)

UDPTCP

IP ICMPICMP IGMP ARP

RouterRouter

Internet Group Management Protocol (IGMP)

UDPTCP

IP ICMP IGMPIGMP ARP

Address Resolution Protocol (ARP)

UDPTCP

IP ICMP IGMP ARPARP

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ARPCache

2

1

4

6

5

1. ARP cache is checked2. ARP request is sent3. ARP entry is added4. ARP reply is sent5. ARP entry is added6. IP packet is sent

ARPCache

3

TCP/IP Utilities

Server-basedSoftware

Diagnostic Utilities

Connectivity Utilities

FtpFtp

TelnetTelnet

TftpTftp

ArpArp

HostnameHostname

IpconfigIpconfig

NbstatNbstat

NetstatNetstat

PingPing

TracertTracert

TCP/IP Printing Service

TCP/IP Printing Service

Internet InformationServices

Internet InformationServices

Name Resolution

Types of Names

Static IP Mapping

Dynamic IP Mapping

Name Resolution in Windows 2000

Types of Names

Host NamesHost Names

Assigned to a computer’s IP address255 characters in lengthCan contain alphabetic and numeric

characters, hyphens, and periods Can take various forms

Alias Domain name

Assigned to a computer’s IP address255 characters in lengthCan contain alphabetic and numeric

characters, hyphens, and periods Can take various forms

Alias Domain name

16-byte address Used to represent a single computer or

group of computers15 of the characters may be used for the

name 16th character is used by the services that

a computer offers to the network

16-byte address Used to represent a single computer or

group of computers15 of the characters may be used for the

name 16th character is used by the services that

a computer offers to the network NetBIOS NamesNetBIOS Names

Static IP Mapping

Provides name resolution for host names to IP addresses

Multiple host names can be assigned to the same IP address

Entries are case sensitive

Provides name resolution for host names to IP addresses

Multiple host names can be assigned to the same IP address

Entries are case sensitive

Provides name resolution for NetBIOS names to IP addresses

A part of the Lmhosts file is pre-loaded into memory

Provides name resolution for NetBIOS names to IP addresses

A part of the Lmhosts file is pre-loaded into memory

Hosts FileHosts File

Lmhosts FileLmhosts File

Dynamic IP Mapping

DNS is a system for naming computers and network services

DNS naming system is organized in a hierarchical fashion

Maps domain names to IP address Mapping records are stored on a DNS

server

DNS is a system for naming computers and network services

DNS naming system is organized in a hierarchical fashion

Maps domain names to IP address Mapping records are stored on a DNS

server

Provides a distributed database for registering dynamic mappings of NetBIOS names

WINS maps NetBIOS names to IP addresses

Provides a distributed database for registering dynamic mappings of NetBIOS names

WINS maps NetBIOS names to IP addresses

DNS ServerDNS Server

WINS ServerWINS Server

Name Resolution in Windows 2000

Enter CommandEnter Command1111

Local Host NameLocal Host Name2222

DNS ServerDNS Server4444

WINS ServerWINS Server6666

LMHOSTSFile

LMHOSTSFile8888

NetBIOS Name CacheNetBIOS Name Cache5555

HOSTSFile

HOSTSFile

3333

7777 BroadcastBroadcast

Host Name Resolution



BroadcastBroadcast4444


HOSTSFile

HOSTSFile

6666

LMHOSTSFile

LMHOSTSFile

5555


NetBIOS Name ResolutionEnter CommandEnter Command1111

Local Host NameLocal Host Name2222



LMHOSTSFile

LMHOSTSFile8888


HOSTSFile

HOSTSFile

3333

7777 BroadcastBroadcast



BroadcastBroadcast4444


HOSTSFile

HOSTSFile

6666

LMHOSTSFile

LMHOSTSFile

5555


Host Name Resolution

NetBIOS Name Resolution


Packet Terminology

Frame Components

Data Flow

Packet Terminology

Segment

Message

Datagram

Frame

Frame Components

HeaderA

lert

Sig

nal

Ale

rt S

igna

l SourceAddressSource

Address

DestinationAddress

DestinationAddress

Data

0.5 KB - 4 KB0.5 KB - 4 KB

Trailer

CRCCRC

Data Flow

UDPUDPTCPTCP

FTPFTPHTTPHTTP

IPIP ICMPICMP IGMPIGMP ARPARP


UDPUDPTCPTCP

FTPFTPHTTPHTTP



Data

ApplicationApplication

DataFTPFTPHTTPHTTP

TransportTransport

Data

UDPUDPTCPTCP

FTPFTPHTTPHTTP

InternetInternet

Data

UDPUDPTCPTCP


PreamblePreamble

Data

CRCCRC



Data


Data


Data



Data

UDPUDPTCPTCP


Data

UDPUDPTCPTCP

FTPFTPHTTPHTTP

PreamblePreamble

Internet

Transport

Application

Data

CRCCRC

FTPFTPHTTPHTTP

Routing Data

IP Routing

Data Transfer Across Routers

IP RoutingIP Routing

RouterRouter

Portion of Routing Table192.168.1.0 255.255.255.0 192.168.1.1192.168.2.0 255.255.255.0 192.168.2.1192.168.3.0 255.255.255.0 192.168.3.1192.168.4.0 255.255.255.0 192.168.4.1192.168.5.0 255.255.255.0 192.168.5.1192.168.6.0 255.255.255.0 192.168.6.1192.168.7.0 255.255.255.0 192.168.7.1192.168.8.0 255.255.255.0 192.168.8.1

Is destination local?Yes, add the destination MAC addressNo, add the Router’s MAC address

Always add the destination’s IP address

Is destination local?Yes, add the destination MAC addressNo, add the Router’s MAC address


Data Transfer Across Routers

Verify packetDecrease TTLIs destination local?

Yes, add the destination MAC addressNo, add another Router’s MAC address


Yes, add the destination MAC addressNo, add another Router’s MAC address

Verify packetVerify IP addressSend the packet up to the next layer

Verify packetVerify IP addressSend the packet up to the next layer

Is destination local?Yes, add the destination MAC addressNo, add the router’s MAC address


Is destination local?Yes, add the destination MAC addressNo, add the router’s MAC address


Verify packet

Verify IP address

Send the packet up to the next layer

Verify packet

Verify IP address

Send the packet up to the next layer


Yes, add the destination MAC addressNo, add another router’s MAC address

Router 2Router 2

Router 1Router 1

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Review



Name Resolution


Routing Data

examining tcp/ip. overview introduction to tcp/ip tcp/ip protocol suite name resolution examining...

Documents

ip addressesa

ip addressentries

ip address mapping records

naming computers

case sensitiveprovides

distributed database

dns serverprovides

tcpip overviewintroduction