70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network, Enhanced Chapter 2: TCP/IP Architecture

Objectives Understand TCP/IP addressing Describe the overall architecture of TCP/IP Describe Application layer protocols Discuss Transport layer protocols Understand the role of various Internet layer protocols, including IP,ICMP, and ARP Understand Network Interface layer protocols 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Introduction To TCP/IP Transmission Control Protocol/Internet Protocol (TCP/IP) Most commonly used network protocol suite today Wide vendor support Open protocol Provides access to Internet services Windows Server 2003 Can use several protocols Many of its main features require the use of TCP/IP 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Activity 2-1: Repairing a Network Connection The purpose of this activity is to repair a connection that has a corrupt TCP/IP configuration 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

IP Addresses An IP address, like a mailing address for a house, is unique An IP addresses has four numbers, each called an octet, that are separated by periods Each octet in an IP address represents eight bits of information A full IP address of four octets is 32 bits long 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

IP Addresses (continued) An example of an IP address is 192.168.5.66 An IP address is composed of two parts: the network ID and the host ID The network ID represents the network on which the computer is located The host ID represents the individual computer on a network 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Subnet Masks A subnet mask defines which part of its IP address is the network ID and which part is the host ID Subnet masks are composed of four octets just like an IP address Wherever there is a 255 in the subnet mask, that octet is part of the network ID Wherever there is a 0 in the subnet mask, that octet is part of the host ID 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Subnet Masks (continued) A computer uses its subnet mask to determine Which network it is on Whether other computers are on the same network or a different network If two computers on the same network are communicating, then they can deliver packets directly to each other If two computers are on different networks, they must use a router to communicate 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Subnet Masks (continued) 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Default Gateway Default gateway is another term for router If a computer does not know how to deliver a packet, it gives the packet to the default gateway to deliver Routers can distinguish multiple networks and how to move packets between them Routers can also figure out the best path to use to move a packet between different networks 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Activity 2-2: Viewing IP Address Configuration The purpose of this activity is to view the current IP address settings on a server 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

IP Address Classes IP addresses are divided into classes: A-E IP address classes can be identified by the first octet Class A addresses use eight bits for the network ID and 24 bits for the host ID Class A networks are only assigned to very large companies and Internet providers Class B addresses use 16 bits for the network ID and 16 bits for the host ID Class B networks are assigned to many larger organizations, such as governments, universities, and companies with several thousand users 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

IP Address Classes (continued) Class C addresses use 24 bits for the network ID and eight bits for the host ID Class C networks have a relatively small number of hosts and are suited only to smaller organizations Class D addresses are not divided into networks and they cannot be assigned to computers as IP addresses Class D addresses are used for multicasting Class E addresses are considered experimental and are not used 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

IP Address Classes (continued) 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Classless Inter-domain Routing Classless interdomain routing (CIDR) makes Internet routing and assignment of IP addresses more efficient CIDR does not use the default subnet masks for routing. Instead, the subnet mask must be defined for each network 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Classless Inter-domain Routing (continued) Definable subnet mask is more flexible and efficient CIDR reduces the number of routing table entries that Internet backbone routers must hold A single routing table entry can replace hundreds or thousands of entries for Class C networks 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Reserved Addresses Reserved addresses are a number of IP addresses and IP networks that are reserved for special purposes and either cannot be assigned to hosts or cannot be used on the Internet 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

DNS Domain Name System (DNS) is used to: resolve host names to IP addresses find domain controllers find e-mail servers DNS is essential for Active Directory to work properly 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

WINS Windows Internet Naming Service (WINS) is used to: resolve NetBIOS names to IP addresses stores information about services such as domain controllers Provide backward compatibility with Windows NT and Windows 9x 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

DHCP Dynamic Host Configuration Protocol (DHCP) is an automated mechanism to assign IP addresses to clients Automating this process avoids the problem of records being entered incorrectly If a change needs to be made for the IP addressing information, you can simply change the information in the DHCP server 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Activity 2-3: Using IPCONFIG to View IP Configuration The purpose of this activity is to view the current IP settings using the IPCONFIG utility 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Activity 2-4: Configuring an Alternative IP Configuration The purpose of this activity is to configure alternative IP address information to be used when a DHCP server is unavailable 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

TCP/IP Architecture Overview The TCP/IP model can be broken down into four layers: Application Transport Internet Network Interface Application layer provides access to network resources It defines rules, commands, and procedures for client to talk to a service running on a server 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

TCP/IP Architecture Overview (continued) Transport layer is responsible for preparing data to be transported across the network Internet layer is responsible for logical addressing and routing Network Interface layer consists of the network card driver and the network card itself 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Application Layer Protocols There are many Application layer protocols, each of which is associated with a client application and service HTTP FTP TELNET SMTP POP3 IMAP4 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

HTTP Hypertext Transfer Protocol (HTTP) is the most common protocol used on the Internet today HTTP defines the commands that Web browsers can send and how Web servers are capable of responding 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

FTP File Transfer Protocol (FTP) is file-sharing protocol FTP is implemented in stand-alone FTP clients as well as in Web browsers It is safe to say that most FTP users today are using Web browsers 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Activity 2-5: Using FTP to Download a File The purpose of this activity is to use FTP to download a utility 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

TELNET Telnet is a terminal emulation protocol that is primarily used to connect remotely to UNIX and Linux Systems The Telnet protocol specifies how a telnet server and telnet client communicate 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

SMTP Simple Mail Transfer Protocol (SMTP) is used to send and receive e-mail messages between e-mail servers that are communicating It is used by e-mail client software, such as Outlook Express, to send messages to the server SMTP is never used to retrieve e-mail from a server when you are reading it Other protocols control the reading of e-mail messages 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Activity 2-6: Using Telnet to Verify SMTP The purpose of this activity is to use Telnet to verify the functionality of an SMTP server 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

POP3 Post Office Protocol version 3 (POP3) is the most common protocol used for reading e-mail messages This protocol has commands to download messages and delete messages from the mail server POP3 does not support sending messages POP3 supports only a single inbox and does not support multiple folders for storage on the server 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

IMAP4 Internet Message Access Protocol version 4 (IMAP4) is another common protocol used to read e-mail messages IMAP4 can download message headers only and allow you to choose which messages to download IMAP4 allows for multiple folders on the server side to store messages 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Transport Layer Protocols Transport layer protocols are responsible for getting data ready to move across the network The most common task performed by Transport layer protocols is breaking entire messages down into packets Transport layer protocols use port numbers Each Transport layer protocol has its own set of ports 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Transport Layer Protocols (continued) When a packet is addressed to a particular port, the Transport layer protocol knows to which service to deliver the packet The combination of an IP address and port number is referred to as a socket 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Transport Layer Protocols (continued) A port number is like an apartment number for the delivery of mail Network ID of the IP address ensures packet is delivered to the correct street (network) Host ID ensures packet is delivered to the correct building (host) Transport layer protocol and port number ensure packet is delivered to the proper apartment (service) 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Activity 2-7: Using Port Numbers The purpose of this activity is to Connect to resources using TCP and UDP port numbers 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

TCP Transmission Control Protocol (TCP) is the most commonly used Transport layer protocol TCP is connection-oriented and reliable Connection-oriented means that TCP creates and verifies a connection with a remote host before sending information Verifies that the remote host exists and is willing to communicate before starting the conversation TCP is the Transport layer protocol used for most Internet services 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Activity 2-8: Installing Network Monitor The purpose of this activity is to install Network Monitor to enable packet capturing 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Activity 2-9: Viewing a TCP Connection in Network Monitor The purpose of this activity is to capture and view TCP connection packets in Network Monitor 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

UDP User Datagram Protocol (UDP) UDP is the appropriate if Not as commonly used as TCP Used for different services Connectionless and unreliable UDP is the appropriate if Unconcerned about missing packets Want to implement reliability in a special way Streaming audio and video are in this category 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Activity 2-10: Capturing UDP Packets in Network Monitor The purpose of this activity is to capture and view UDP packets in Network Monitor 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

TCP versus UDP TCP is connection-oriented and reliable Like registered mail UDP is connectionless and unreliable Like sending a message split on several postcards and assuming that the receiver will be able to put the message together 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Internet Layer Protocols Internet layer protocols are responsible for all tasks related to logical addressing An IP address is a logical address Any protocol that is aware of other networks exists at this layer Each Internet layer protocol is very specialized They include: IP, RIP and OSPF, ICMP, IGMP, and ARP 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

IP Internet Protocol (IP) is responsible for the logical addressing of each packet created by the Transport layer As each packet is built, IP adds the source and destination IP address to the packet 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

RIP and OSPF Routing Information Protocol (RIP) and Open Shortest Path First (OSPF) are both routing protocols They are responsible for defining how paths are chosen through the internetwork from one computer to another They also define how routers can share information about the networks of which they are aware 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

ICMP Internet Control Messaging Protocol (ICMP) is used to send IP error and control messages between routers and hosts The most common use of ICMP is the ping utility 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Activity 2-11: Testing Host Functionality The purpose of this activity is to test the functionality of a host using the ping command 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Activity 2-12: Viewing TTL The purpose of this activity is to view the TTL of a ping packet 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

IGMP Internet Group Management Protocol (IGMP) is used for the management of multicast groups Hosts use IGMP to inform routers of their membership in multicast groups Routers use IGMP to announce that their networks have members in particular multicast groups The use of IGMP allows multicast packets to be distributed only to routers that have interested hosts connected 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

ARP Address Resolution Protocol (ARP) is used to convert logical IP addresses to physical MAC addresses This is an essential part of the packet delivery process 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Activity 2-13: Viewing the ARP Cache The purpose of this activity is to View the contents of the ARP cache 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Network Interface Layer Protocols Most of the common Network Interface layer protocols are defined by the Institute of Electrical and Electronics Engineers (IEEE) 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Summary Windows Server 2003 uses TCP/IP as its primary networking protocol An IP address has a network ID and a host ID A subnet mask defines which part of the IP address is the network ID and which is host ID A default gateway is required to deliver packets of information from one network to another The TCP/IP model is composed of four layers: Application, Transport, Internet, Network Interface 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

Summary (continued) HTTP is the most common protocol used on the Internet today The two Transport layer protocols are TCP and UDP Internet layer protocols are responsible for all tasks related to logical addressing and are all very specialized Internet layer protocols include IP, RIP, OSPF, ICMP, IGMP, and ARP 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network