Network Administration for the Solaris 9 Operating Environment SA399 Student Guide docx

Configuring DNS ConfiguringDHCP ConfiguringNTP Configuring Routing ConfiguringIPv6 Describing the Transport Layer Introducing the TCP/IP Model Introducing LANs and Their Components Descr

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Student Guide

Solaris™ 9 Operating

Environment

SA-399

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About This Course xv

Instructional Goals xv

Course Map xvi

Topics Not Covered xvii

How Prepared Are You? xviii

Introductions xix

How to Use Course Materials xx

Conventions xxi

Icons xxi

Typographical Conventions xxi

Introducing the TCP/IP Model 1-1

Objectives 1-1 Introducing Network Model Fundamentals 1-2 Network Protocols 1-2 Network Model Concepts 1-3 Introducing the Layers of the TCP/IP Model 1-4 Network Interface Layer 1-5 Internet Layer 1-6 Transport Layer 1-7 Application Layer 1-8 Describing Basic Peer-to-Peer Communication and Related

Protocols 1-10 Peer-to-Peer Communication 1-10 TCP/IP Protocols 1-11 Exercise: Reviewing the TCP/IP Model 1-15 Tasks 1-15 Exercise Summary 1-17 Exercise Solutions 1-18

Introducing Network Topologies 2-2Bus Topologies 2-2Star Topologies 2-3Ring Topologies 2-4VLAN Topologies 2-5Introducing LAN Media 2-9IEEE Identifiers 2-9IEEE 802.3 Type 2-10Introducing Network Devices 2-14Shared Hubs 2-14Bridges 2-14Switches 2-14Exercise: Reviewing LANs and Their Components 2-16Preparation 2-16Tasks 2-16Exercise Summary 2-18Exercise Solutions 2-19

Describing Ethernet Interfaces 3-1

Objectives 3-1Introducing Ethernet Concepts 3-2Major Ethernet Elements 3-2CSMA/CD Access Method 3-2Full-Duplex and Half-Duplex Transmission 3-4Ethernet Statistics 3-4Introducing Ethernet Frames 3-6Ethernet Addresses 3-6Setting a Local Ethernet Address 3-8Ethernet-II Frame Analysis 3-10Ethernet Frame Encapsulation 3-11Maximum Transfer Units 3-13Ethernet Frame Errors 3-14Using Network Utilities 3-15Using thesnoop Utility 3-15Using thenetstat Utility 3-18Using thendd Utility 3-19Exercise: Reviewing Ethernet Interfaces 3-22Preparation 3-22Tasks 3-22Exercise Summary 3-26Exercise Solutions 3-27

Introducing ARP 4-2Purpose of ARP 4-2Operation of ARP 4-3Introducing RARP 4-7Purpose of RARP 4-7Operation of RARP 4-7Exercise: Reviewing ARPs and RARPs 4-10Preparation 4-10Tasks 4-11Exercise Summary 4-14Exercise Solutions 4-15

Configuring IP 5-1

Objectives 5-1Introducing the Internet Layer Protocols 5-2Purpose of IP 5-2Purpose of ICMP 5-3Introducing the IP Datagram 5-5

IP Datagram Header Fields 5-5

IP Datagram Payload 5-6Introducing IP Address Types 5-7Unicast Addresses 5-7Broadcast Addresses 5-8Multicast Addresses 5-9Introducing Subnetting and VLSM 5-10Subnetting 5-10The/etc/inet/netmasks File 5-11VLSM 5-12Introducing the Interface Configuration Files 5-14The/etc/hostname.interface File 5-14The/etc/inet/hosts File 5-14The/etc/nodename File 5-15Administering Logical Interfaces 5-16Introducing Logical Interfaces 5-16Configuring Logical Interfaces 5-17Unconfiguring Logical Interfaces 5-20Exercise: Reviewing IP 5-21Preparation 5-21Task Summary 5-21Tasks 5-22Exercise Summary 5-24Exercise Solutions 5-25

Increasing Network Throughput and Availability 6-2Limitations of Network Interfaces 6-2Implementing Multipathing 6-4Introducing Multipathing 6-4Configuring Multipathing Using Configuration Files 6-7Configuring Multipathing Using the

Command Line 6-12Viewing Multipath Operation 6-20Troubleshooting a Multipath

Network Configuration 6-22Exercise: Reviewing Multipathing 6-24Preparation 6-24Tasks 6-26Exercise Summary 6-30Exercise Solutions 6-31

Configuring Routing 7-1

Objectives 7-1Identifying the Fundamentals of Routing 7-2Purpose of Routing 7-2Routing Types 7-3Introducing Route Table Population 7-4Static Route 7-4Dynamic Route 7-4Introducing Routing Protocol Types 7-6Autonomous Systems 7-6Interior Routing Protocols 7-7Exterior Routing Protocols 7-8Introducing the Route Table 7-9Displaying the Route Table 7-9Introducing Route Table Entries 7-10Introducing Route Table Search Order 7-12Associating Network Name and Network Number 7-14Configuring Static Routes 7-16Configuring Static Direct Routes 7-16Configuring the/etc/defaultrouter File 7-16Configuring the/etc/gateways File 7-17Configuring Manual Static Routes 7-18Using the RDISC Protocol 7-21Configuring Dynamic Routing 7-23RIP Version 1 7-23

Operation of CIDR 7-28Configuring Routing at Boot Time 7-32Initializing the Router 7-32Configuring the Router Without Rebooting 7-34Initializing a Multihomed Host 7-34Initializing a Non-Router 7-36Troubleshooting Routing 7-37Troubleshooting the Router Configuration 7-37Troubleshooting Network Names 7-39Exercise: Reviewing Routing Configuration 7-40Preparation 7-40Tasks 7-42Exercise Summary 7-53Exercise Solutions 7-54

Configuring IPv6 8-1

Objectives 8-1Introducing IPv6 8-2The Need for IPv6 8-2Features of IPv6 8-3Introducing IPv6 Addressing 8-4Address Types 8-4IPv6 Address Representation 8-5Format Prefixes 8-5Introducing IPv6 Autoconfiguration 8-7Stateful Autoconfiguration 8-7Stateless Autoconfiguration 8-7Interface Identifier Calculation 8-8Duplicate Address Detection 8-9Introducing Unicast Address Types 8-10Link-Local Address Types 8-10Site-Local Address Types 8-10Aggregatable Global Unicast Address Types 8-11Prefix Notation 8-11Embedded IPv4 Addresses 8-12Unspecified Address Types 8-12Loopback Address Types 8-12Introducing Multicast Address Types 8-13Purpose of Multicast Addresses 8-13Scope Bits 8-14ICMPv6 Group Membership 8-15Enabling IPv6 8-16Thein.ndpd Process on the Non-Router 8-16IPv6 on Non-Routers Configuration 8-17

IPv6 Routing Information Protocol 8-21IPv6 Router Configuration 8-22Router Configuration Troubleshooting 8-26Managing IPv6 8-28Displaying the State of IPv6 Interfaces 8-28Modifying an IPv6 Interface Configuration 8-28Configuring Logical Interfaces 8-29Troubleshooting IPv6 Interfaces 8-29Displaying the IPv6 Route Table 8-29Exercise: Configuring IPv6 8-30Preparation 8-30Tasks 8-30Exercise Summary 8-36Exercise Solutions 8-37Configuring IPv6 Multipathing 8-47Configuring IPMP Manually 8-47Configuring IPMP at Boot Time 8-57Exercise: Configuring IPv6 Multipathing 8-61Preparation 8-61Tasks 8-61Exercise Summary 8-64Exercise Solutions 8-65Configuring IPv6-Over-IPv4 Tunnels 8-70Introducing Tunnels 8-70Configuring Tunnels 8-70Routing Between Tunnels 8-77Troubleshooting IPv4 Tunnels 8-77Exercise: Configuring an IPv6-Over-IPv4 Tunnel 8-79Preparation 8-79Tasks 8-79Exercise Summary 8-81Exercise Solutions 8-82

Describing the Transport Layer 9-1

Objectives 9-1Introducing Transport Layer Fundamentals 9-2Protocol Characteristics 9-2Transport Protocols in TCP/IP 9-8Introducing UDP 9-9Purpose of UDP 9-9UDP Datagram Header 9-9

Buffered Transfer 9-11 Introducing TCP Flow Control 9-12 Receiver-Side Window Advertisements 9-12 Sender-Side Congestion Window 9-12 TCP Large Window 9-13 Exercise: Describing the Transport Layer 9-14 Preparation 9-14 Tasks 9-14 Exercise Summary 9-15 Exercise Solutions 9-16

Configuring DNS 10-1

Objectives 10-1 Introducing DNS Basics 10-2 BIND 10-2 Top-Level Domains 10-2 Zones of Authority 10-4 Server Types 10-4 Answer Types 10-7 Name-Resolution Process 10-7 Resource Records 10-10 Configuring the DNS Server 10-14 Gathering Information 10-14 Editing the BIND Configuration File 10-14 Editing thenamed.root File 10-17 Editing the Forward-Domain File 10-19 Editing the Reverse-Domain File 10-21 Editing the Reverse-Loopback Domain File 10-22 Configuring Dynamic Updates 10-23 Configuring Security 10-23 Configuring Secondary DNS Servers 10-25 Configuring DNS Clients 10-26 Troubleshooting the DNS Server Using Basic Utilities 10-28 Examining the/var/adm/messages File 10-28 Using thenslookup Utility 10-29 Dumping a Snapshot of the DNS Database 10-31 Changing the Debug Level of the Name Daemon 10-31 Forcing thein.named Process to Reread Configuration Files 10-32

Modifying the DNS Server With thendc Utility 10-32 Exercise: Configuring DNS 10-34 Preparation 10-34 Task Summary 10-34 Tasks 10-35

Introducing the Fundamentals of DHCP 11-2Purpose of DHCP 11-2DHCP Client Functions 11-3DHCP Server Functions 11-4Configuring a DHCP Server 11-6Configuring DHCP Using Different Methods 11-7Using thedhcpconfig Utility 11-7Introducing thedhcp_network File 11-9Using thepntadm Utility 11-10Introducing thedhcptab Table 11-13Performing Initial DHCP Server Configuration by

Using thedhcpmgr Utility 11-17Adding Addresses by Using thedhcpmgr Utility 11-29Configuring and Managing DHCP Clients 11-37Configuring the DHCP Client 11-37Exercise: Configuring a DHCP Server and Client 11-39Preparation 11-39Task Summary 11-39Tasks 11-39Exercise Summary 11-42Exercise Solutions 11-43Task 1 – Configuring the DHCP Server 11-43Task 2 – Configuring the DHCP Client 11-61Task 3 – Using thesnoop Utility to View DHCP

Client-Server Interaction 11-62Configuring for Dynamic DNS 11-64Viewing Debug Output From the DNS Server 11-67Troubleshooting the DHCP Server 11-68Troubleshooting DHCP Clients 11-72Troubleshooting DHCP Client Host

Name Acquisition 11-72Configuring the DHCP Server to Support

JumpStart Clients 11-80Comparing Conventional JumpStart Procedure

With DHCP JumpStart Procedure Clients 11-80Performing a Configuration 11-80Configuring a DHCP Server to Allow a Client to

Boot From a JumpStart Server 11-86Configuring the JumpStart Server to Support

JumpStart in DHCP 11-106Testing the Client’s Ability to Jump Start by

Task Summary 11-109Tasks 11-110Exercise Summary 11-112Exercise Solutions 11-113Task 1 – Configuring DNS to Support Dynamic

DNS Updates 11-113Task 2 – Configuring the DHCP Server to Perform

Dynamic DNS Updates 11-113Task 3 – Configuring the DHCP Server to Allow a

Client to Boot from a JumpStart Server 11-116

Configuring NTP 12-1

Objectives 12-1Identifying NTP Basics 12-2How Computers Keep Time 12-2Uses of NTP 12-3NTP Terms 12-3Configuring an NTP Server 12-5Using an Undisciplined Local Clock 12-7Using External NTP Reference Servers 12-9Managing Daemons 12-10Determining NTP Peers 12-11Configuring an NTP Client 12-12Establishing Basic Configuration 12-12Managing NTP Client Daemons 12-13Troubleshooting NTP 12-14Viewing Messages 12-14Using thesnoop Utility 12-15Exercise: Configuring NTP 12-16Preparation 12-16Task Summary 12-16Tasks 12-16Exercise Summary 12-19Exercise Solutions 12-20

Bibliography Bibliography-1

Sun Microsystems Publications Bibliography-1Books Bibliography-1Online References Bibliography-2Requests for Comments (RFCs) Bibliography-3

Glossary/Acronyms Glossary-1 Index Index-1

About This Course

Instructional Goals

Upon completion of this course, you should be able to:

● Configure the Network Interface layer

● Configure the network (Internet and Transport layers)

● Configure and manage network applications

Course Map

The course map enables you to see what you have accomplished andwhere you are going in reference to the instructional goals

Configuring DNS ConfiguringDHCP ConfiguringNTP

Configuring Routing ConfiguringIPv6

Describing the Transport Layer

Introducing the TCP/IP Model

Introducing LANs and Their Components

Describing Ethernet Interfaces

Describing ARP and RARP

Configuring the Network Interface Layer

Configuring the Network

Configuring

IP MultipathingConfiguring

Configuring and Managing Network Applications

Topics Not Covered

This course does not cover the following topics Many of these topics arecovered in other courses offered by Sun Educational Services:

● Solaris™ Operating Environment (Solaris OE) system

administration – Covered in SA-239: Intermediate System

Administration for the Solaris™ 9 Operating Environment and

SA-299: Advanced System Administration for the Solaris™ 9 Operating

Environment

● Server storage administration – Covered in ES-220: Disk Management

with DiskSuite™ and ES-310: Volume Manager With Sun StorEdge™

● NIS+ – Covered in SA-385: NIS+ Administration

● Solaris OE tuning – Covered in SA-400: Solaris™ Systems Performance

Management

Refer to the Sun Educational Services catalog for specific information andregistration

How Prepared Are You?

To be sure you are prepared to take this course, can you answer yes to thefollowing questions?

● Can you perform basic host operations, such as startup andshutdown, to initialize certain network configuration changes?

● Can you manipulate startup and shutdown scripts to configurenetworks?

● Can you set up user accounts when configuring network services forsystem users?

● Can you locate and install network software packages required to set

up various network services?

● Title, function, and job responsibility

● Experience related to topics presented in this course

● Reasons for enrolling in this course

● Expectations for this course

How to Use Course Materials

To enable you to succeed in this course, these course materials employ alearning module that is composed of the following components:

● Objectives – You should be able to accomplish the objectives aftercompleting a portion of instructional content Objectives supportgoals and can support other higher-level objectives

● Lecture – The instructor will present information specific to theobjective of the module This information will help you learn theknowledge and skills necessary to succeed with the activities

● Activities – The activities take on various forms, such as an exercise,self-check, discussion, and demonstration Activities are used tofacilitate mastery of an objective

● Visual aids – The instructor might use several visual aids to convey aconcept, such as a process, in a visual form Visual aids commonlycontain graphics, animation, and video

Note – Many system administration tasks for the Solaris OE can be

accomplished in more than one way The methods presented in thecourseware reflect recommended practices used by Sun EducationalServices

Discussion – Indicates a small-group or class discussion on the current

topic is recommended at this time

Note – Indicates additional information that can help students but is not

crucial to their understanding of the concept being described Studentsshould be able to understand the concept or complete the task withoutthis information Examples of notational information include keywordshortcuts and minor system adjustments

Caution – Indicates that there is a risk of personal injury from a

nonelectrical hazard, or risk of irreversible damage to data, software, orthe operating system A caution indicates that the possibility of a hazard(as opposed to certainty) might happen, depending on the action of theuser

Typographical Conventions

Courieris used for the names of commands, files, directories, usernames, host names, programming code, and on-screen computer output;for example:

Use thels -alcommand to list all files

Courier italicsis used for variables and command-line placeholdersthat are replaced with a real name or value; for example:

To delete a file, use thermfilenamecommand

Courier italic boldis used to represent variables whose values are to

be entered by the student as part of an activity; for example:

Type chmod a+rwx filenameto grant read, write, and executerights for filename

Palatino italics is used for book titles, new words or terms, or words that

you want to emphasize; for example:

Read Chapter 6 in the User’s Guide.

These are called class options.

Introducing the TCP/IP Model

Objectives

This module describes the fundamentals of the Transmission ControlProtocol/Internet Protocol (TCP/IP) model, including network protocolsand concepts This module also describes the layers of the TCP/IP model,including the Network Interface, Internet, Transport, and Applicationlayers This module also describes basic peer-to-peer communication andsome common TCP/IP protocols

Upon completion of this module, you should be able to:

● Describe the layers of the TCP/IP model

● Describe basic peer-to-peer communication and related protocols

The following course map shows how this module fits into the currentinstructional goal

Figure 1-1 Course Map

Introducing the TCP/IP Model

Introducing LANs and Their Components

Describing Ethernet Interfaces

Describing ARP and RARP

Configuring the Network Interface Layer

Introducing Network Model Fundamentals

The fundamentals required to understand computer networking are thenetwork model, the functions of the layers, and the protocols that governdata transfer between two or more systems

Network Protocols

Computer networks use protocols to communicate Protocols define theprocedures to be followed by the systems involved in the communicationprocess A data communication protocol is a set of rules that must befollowed for two electronic devices to communicate with each other.These rules describe:

● Syntax – Data format and coding

● Semantics – Control information and error handling

● Timing – Speed matching and sequencingFunctions of Protocols

A protocol defines how systems can communicate and facilitatescommunication between software, firmware, and other devices in datatransfer

Each protocol provides a function essential for data communication Eachsoftware module that implements a protocol can be developed andupdated independently of other modules, as long as the interface betweenthe modules remains constant

Many protocols provide and support data communication Manyprotocols are used so that communication can be broken into smaller,manageable processes They form a communication architecture, alsoknown as a protocol stack The TCP/IP model is a protocol stack used bythe Solaris™ Operating Environment (Solaris OE) for data

communication

The features of a protocol stack are:

● Each layer has a specific purpose and exists on both the sourceand destination hosts

● Each layer communicates with a peer layer on another host in agiven process of communication

● Each layer on a host acts independently of other layers on thesame machine but is synchronous with the same layer on otherhosts

Network Model Concepts

A networking model refers to a common structure that enables

communication between two or more systems

Networking models consist of layers You can think of layers as a series ofsteps or functions that must be sequentially completed for communication

to occur between two systems

The following mapping helps you better understand the network model:

● Protocol = rules

Advantages of Using a Layered Model

Some of the advantages of a layered model are that it:

● Divides the complexity of networking into many functions or layers

● Enables you to introduce changes or new features in one layer

without having to change the other layers

● Provides a standard to follow, allowing inter-operability betweensoftware and hardware vendors

● Simplifies troubleshooting

Introducing the Layers of the TCP/IP Model

Table 1-1 shows that the TCP/IP model is a four-layered structure resting

on a common hardware platform The TCP/IP model was developed bythe Department of Defense (DOD) in 1979 It has standards that aredefined and described in Request for Comment (RFC) documents

RFCs are a frame of reference for describing the protocol architecture andfunctions specific to the TCP/IP protocol stack For a complete listing ofRFCs, visit http://www.ietf.org/rfc.html

Table 1-1 TCP/IP Network Model TCP/IP Layer Description

Application ● Consists of user-accessed application programs

and network services

● Defines how cooperating networks representdata

acknowledged and unacknowledged transportprotocols

● Manages the connections between cooperatingapplications

Network Interface Layer

Figure 1-2 shows the Network Interface layer The primary functions ofthis layer are:

● Managing the delivery of data across the physical network

● Detecting errors

Figure 1-2 TCP/IP Network Interface Layer

The Network Interface layer services the Internet layer by providingcommunication between nodes on the same network This layer defineshow bits are assembled into manageable units of data A packet data unit(PDU) is a series of bits with a well-defined beginning and a well-definedend Figure 1-3 shows a specific type of PDU known as an Ethernet frame,where the bits are divided into fields containing information labels, such

as preamble, destination and source hardware address, frame length ortype, data, and cyclic redundancy check (CRC)

Figure 1-3 Structure of a Frame

Hardware Layer

TCP/IP Layers Application Layer Transport Layer Internet Layer

Network Interface Layer

Packet

data unit

Preamble DestinationAddress AddressSource Type Data CRC

Examples of Network Interface layer protocols are:

● Institute of Electrical and Electronics Engineers (IEEE) 802.3 –Ethernet standards

● IEEE 802.4 – Token bus standards

● IEEE 802.5 – Token ring standards

Internet Layer

The Internet layer attempts to ensure that messages reach theirdestination system using the most efficient route Figure 1-4 shows thelocation of this layer The primary functions of the Internet layer are:

● Fragmenting and reassembly of data

Figure 1-4 TCP/IP Internet Layer

Using a routing table, the Internet layer determines the next directlyaccessible node in route to the packet’s destination This node is either thedestination itself or the most immediate gateway to the destination TheInternet layer uses the Internet Protocol (IP) and Internet Control MessageProtocol (ICMP) The IP is responsible for fragmenting and routing data,while ICMP assists routing, and performs error detection and othernetwork management tasks IP encapsulates data into datagrams, which

Hardware Layer

TCP/IP Layers Application Layer Transport Layer

Internet Layer

Network Interface Layer Datagram

Transport Layer

The Transport layer manages the transfer of application data betweencommunication hosts It also controls the flow of data and defines thetransport quality of the data transmission Figure 1-5 shows the location

of the Transport layer

Figure 1-5 TCP/IP Transport Layer

The mechanisms used by the Transport layer to determine whether datahas been correctly delivered are:

The Transport layer facilitates end-to-end data transfer It supports

multiple operations simultaneously The layer is implemented by twoprotocols: the Transmission Control Protocol (TCP) and the User

Datagram Protocol (UDP) TCP uses packets called segments, while UDPuses packets called datagrams Both TCP and UDP are encapsulatedinside Internet layer datagrams for transmission to the next node

Hardware Layer

TCP/IP Layers Application Layer

Transport Layer

Internet Layer Network Interface Layer

Segment

or

datagram

The Transport layer facilitates two types of communication:

● Connection-oriented (TCP) – A connection must be established at theTransport layer of both systems before the application can transmitany data

● Connectionless (UDP) – All systems do not need to establish aconnection with the recipient prior to data exchange

TCP is a more reliable form of data exchange than UDP

Application Layer

The top layer of TCP/IP is the Application layer Figure 1-6 shows thelocation of this layer

Figure 1-6 TCP/IP Application Layer

The Application layer includes all the processes that use Transport layerprotocols to deliver data to the Internet layer There are many applicationprotocols, and new protocols are frequently added

Some common TCP/IP applications include:

● Telnet Protocol

Stream or message

Hardware Layer

TCP/IP Layers

Application Layer

Transport Layer Internet Layer Network Interface Layer

● Dynamic Host Configuration Protocol (DHCP)

● Network Information Service (NIS)

● Secure shell (SSH)

The Application layer handles the details of the particular application.The primary functions of this layer are:

● Formatting data – Data is formatted based on a computer’s

architecture For example, text formatting is done in AmericanStandard Code for Information Interchange (ASCII) on a UNIX®

host, and Extended Binary Coded Decimal Interchange Code

(EBCDIC) on an IBM mainframe computer Protocols operating atthis layer of the model encapsulate packets into streams or messages

● Presenting data – If end users specify how they want their datapresented to them, the Application layer makes sure that it reachesthe end users in this format A common syntax ensures compatibilitybetween various end-user applications and machines The

Application layer also provides translations between locally

represented data and data used for transfer between end systems

● Transporting data – The Application layer stipulates a transfer

syntax, which represents a coding agreement for the data to beformatted and transferred remote procedure call (RPC) librariesallow high-level language programs to make procedure decisions onother machines on the network to organize the flow of data

Protocols, such as NIS and NFS, use RPC for session managementbetween clients and servers

Describing Basic Peer-to-Peer Communication and

Related Protocols

In the TCP/IP model, peer-to-peer communication occurs when one layer

of a system communicates with a corresponding layer of another system.Peer-to-Peer Communication

Each layer on the sender encapsulates the data and adds headerinformation about the corresponding protocol layer The headerinformation helps the receiving host decapsulate the data and direct themessage to the appropriate application Figure 1-7 shows how header (H)and trailer (T) information is added or removed as the PDUs traverse eachlayer

Figure 1-7 Peer-to-Peer Communication

Application Layer

Transport Layer

Internet Layer

Network Interface Layer Hardware Layer

Frame Signal

Message or Stream

Segment or Datagram Datagram

Frame

Encapsulation Decapsulation

Message or Stream

Segment or Datagram Datagram

IH T-PDU TH

User Data

A-PDU

IH T-PDU TH

User Data

A-PDU

Data encapsulation occurs when:

● Data travels down through layers at the source system’s end

● Headers and trailers are added before the data is passed down to thenext successive layer

Data decapsulation occurs when:

● Data travels up through layers at the destination system’s end

● Headers and trailers are removed before the data is passed up to thenext layer

TCP/IP Protocols

The following tables briefly describe the common TCP/IP protocols

Table 1-2 shows a list of the Network Interface layer protocols, theircorresponding RFCs, and a short description of each protocol

Table 1-2 TCP/IP Network Interface Layer Protocols Descriptions

Table 1-3 shows a list of the Internet layer protocols, their correspondingRFCs, and a short description of each protocol.

Table 1-3 TCP/IP Internet Layer Protocol Descriptions

IP address to a 48-bit Ethernet address

map a 48-bit Ethernet address to a 32-bit IP address

791, 950,

919, 922

IP Internet Protocol determines the path a datagram must take, based

on the destination host’s IP address

and other controls within IP datagrams

IPSec-• Internet Protocol Security Architecture

• Encapsulating Security Payload (ESP)

• IP authentication header

• Internet IP security domain of interpretation for the InternetSecurity Association and Key Management Protocol (ISAKMP)

• ISAKMP

Table 1-4 shows a list of the Transport layer protocols, their correspondingRFCs, and a short description of each protocol.

Table 1-5 shows a list of the Application layer protocols, their

corresponding RFCs, and a short description of each protocol

Table 1-4 TCP/IP Transport Layer Protocol Descriptions

connection-oriented protocol thatprovides the full-duplex, stream service

on which many application protocolsdepend

connectionless protocol that providesnon-acknowledged datagrams deliveredover reliable networks

Table 1-5 TCP/IP Application Layer Protocol Descriptions

distributed IP address database Domainnames index a hierarchical tree of namesand ultimately identify hosts and

domains

copying a complete file from one system

to another system

terminal-oriented processes tocommunicate on a network by usingTCP/IP

1258, 1280 Remote login Therlogin utility enables users to log in

to remote server locations anywhere onthe Internet

responsible for automatically assigning IPaddresses in an organization’s network

821 SMTP Simple Mail Transfer Protocol transfers

electronic mail (email) messages from onemachine to another

enables remote system administrators tomonitor and control network devices

users to access their email box across awide area network (WAN) or local areanetwork (LAN) from a POP3 server

version 4, enables users to access theiremail box across the network from anIMAP4 server IMAP4 is suited to mobileusers because the mail remains on theserver IMAP4 is server-centric, whereasPOP3 is client-centric

the World Wide Web to transfer text,pictures, audio, and other multimediainformation accessible through a webbrowser

T Ylonen written November 15, 1995,expired May 15, 1996 SSH securely logs

in to a system across a network

systems on a network

Table 1-5 TCP/IP Application Layer Protocol Descriptions (Continued)

Exercise: Reviewing the TCP/IP Model

In this exercise, you review the TCP/IP model

Tasks

Perform the following steps:

1 List the layers of the TCP/IP network model by their name andfunction

Name: _Function:

Name: _Function:

Name: _Function:

Name: _Function:

2 In your own words, define the term peer-to-peer.

3 In your own words, define the term protocol.

_

4 Which of the following protocols are part of the TCP/IP suite?

5 Which of the following describes data encapsulation?

a Data travels up through layers at the destination system’s end

b Data travels down through layers at the source system’s end

c Headers and trailers are removed before the data is passed up

to the next layer

d Headers and trailers are added before the data is passed down

to the next successive layer

Exercise Summary

?

!

Discussion – Take a few minutes to discuss what experiences, issues, or

discoveries you had during the lab exercise

● Interpretations

Exercise Solutions

1 List the layers of the TCP/IP network model by their name andfunction

Name: Application Function: Consists of user-accessed application programs and network services This layer is also responsible for defining the way in which cooperating networks represent data.

Name: Transport Function: Manages the transfer of data using connection-oriented and connectionless transport protocols.

Name: Internet Function: Manages data addressing and delivery between networks, as well

as fragmenting data for the Network Interface layer.

Name: Network Interface Function: Manages the delivery of data across the physical network This layer provides error detection and packet framing.

2 In your own words, define the term peer-to-peer.

Peer-to-peer communication is the ability of a specific layer to communicate with a corresponding layer on another host.

3 In your own words, define the term protocol.

A protocol is set of rules governing the exchange of data between two entities These rules describe:

● Syntax – Data format and coding

● Semantics – Control information and error handling

● Timing – Speed matching and sequencing

4 Which of the following protocols are part of the TCP/IP suite?

a ARP

d ICMP

5 Which of the following describes data encapsulation?

b Data travels down through layers at the source system’s end.

d Headers and trailers are added before the data is passed down to the