CH09 - McGraw-Hill Higher Education

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26 Οκτ 2013 (πριν από 3 χρόνια και 8 μήνες)

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Network Protocols


Transmission Control Protocol/Internet Protocol (TCP/IP)


Asynchronous Transfer Mode (ATM)


NWLink


NetBIOS Enhanced User Interface (NetBEUI)


AppleTalk


Data Link Control (DLC)


Infrared Data Association (IrDA)

Introduction to Network
Protocols


A protocol is a set of rules and conventions for sending
information over a network.


Protocols can be added or deleted at will and selectively bound
to all network interfaces.


Binding order is determined by the order in which the protocols
were initially installed.


Binding order can be changed at any time on a per
-
interface
basis.


Network services can be selectively enabled or disabled on a
per
-
adapter or per
-
protocol basis.

TCP/IP


The TCP/IP suite has been adopted by Microsoft as the strategic
enterprise transport protocol for Microsoft Windows 2000.


The Windows 2000 TCP/IP suite is designed to make it easy to
integrate Microsoft enterprise networks into large
-
scale
corporate, government, and public networks.

ATM

NWLink


NWLink is Microsoft’s implementation of the Novell NetWare
IPX/SPX protocol.


NWLink supports a number of topologies and frame types.

NetBEUI


NetBEUI is broadcast
-
based and is not routable.


NetBEUI provides compatibility with existing LANs that use the
NetBEUI protocol.


NetBEUI provides computers running Windows 2000 with
several capabilities.

AppleTalk


Windows 2000 includes support for AppleTalk.


AppleTalk allows Windows 2000 to be a router and a dial
-
up
server.


For the AppleTalk protocol to function properly, a Windows 2000
Server computer must be configured with Services for Macintosh
and must be available on the network.

DLC

IrDA


IrDA is a group of short
-
range, high
-
speed, bidirectional wireless
infrared protocols.


IrDA allows a variety of devices to communicate with one
another.


The IrDA protocol stack is accessed by using Network Driver
Interface Specification (NDIS) connectionless drivers.

Overview of the TCP/IP
Suite

Configuring TCP/IP to Use a
Static IP Address

Configuring TCP/IP to
Obtain an IP Address
Automatically


Using DHCP


Using the Internet Protocol (TCP/IP) Properties dialog box to
configure a DHCP client

Using Automatic Private IP
Addressing


Windows 2000 implementation of TCP/IP.


Automatic Private IP Addressing (APIPA) follows specific steps in
assigning an IP address.


After the computer generates the address, it broadcasts to this
address and then assigns the address to itself if no other
computer responds.


Although APIPA can assign a TCP/IP address to Dynamic Host
Configuration Protocol (DHCP) clients, it does not generate all
the information that is provided by DHCP.


Disabling automatic private IP addressing.

Troubleshooting TCP/IP

Windows 2000 offers several utilities to assist you in
troubleshooting TCP/IP.

TCP/IP Utilities


File Transport Protocol (FTP)


Trivial File Transport Protocol (TFTP)


Telnet


Remote Copy Protocol (RCP)


Remote shell (RSH)


Remote execution (REXEC)


Finger

Using Ipconfig


Use ipconfig to verify the TCP/IP configuration parameters on a
host.


Executing the ipconfig /all command provides several results.

Using Ping


To test connectivity


To test TCP/IP configurations and diagnose connection failures


To determine whether a particular TCP/IP host is available and
functioning

Using Ipconfig and Ping


The ipconfig command is used to verify that the TCP/IP
configuration has been initialized.


The ping command is used against the loopback address
(127.0.0.1) to verify that TCP/IP is correctly installed and bound
to your network adapter card.


The ping command is used with the IP address of the local
computer to verify that the computer is not a duplicate of
another IP address on the network.


The ping command is used with the IP address of the default
gateway to verify that the default gateway is operational and
that the computer can communicate with the local network.


The ping command is used with the IP address of a remote host
to verify that the computer can communicate through a router.

Overview of DHCP


DHCP is a TCP/IP standard for simplifying the management of IP
configuration.


Each time a DHCP client starts, it requests IP addressing
information from a DHCP server.


When a DHCP server receives a request for an IP address, it
selects IP addressing information from a pool of addresses
defined in its database and offers the IP addressing information
to the DHCP client.

The DHCP Lease Process

Installing the DHCP Service


The first step in implementing DHCP is to install the DHCP
Service.


To install the DHCP Service, use the Add/Remove Programs
utility in Control Panel.

The DHCP Snap
-
In

Creating a DHCP Scope


After you have installed the DHCP Service and it is running, the
next step is to create a scope.


When creating a DHCP scope, consider several guidelines.


Use the DHCP snap
-
in to create a scope.


You can specify a number of parameters when creating a new
scope.


Once you have created the scope, you must activate it to make
it available for lease assignments.

Configuring a Client
Reservation

Authorizing the DHCP
Server


A DHCP server must be authorized in Active Directory services
before it can assign IP addresses.


Authorization is a security precaution that ensures that only
authorized DHCP servers run on your network.


Use the DHCP snap
-
in to authorize the DHCP server.

The WINS Name Resolution
Process


Every time a WINS client starts, it registers its NetBIOS name/IP
address mapping with a designated WINS server. It then queries
the WINS server for the computer name resolution.


When a WINS client initiates a NetBIOS command to
communicate with another network resource, it sends the

name query request directly to the WINS server instead of
broadcasting the request on the local network.


The WINS server finds a NetBIOS name/IP address mapping for
the destination resource in this database, and it returns the IP
address to the WINS client.

Name Renewal


A WINS server registers all NetBIOS names on a temporary
basis so that other computers can use the same name later if
the original owner stops using it.


To continue using the same NetBIOS name, a client must renew
its lease before the lease expires.


A WINS client first attempts to refresh its lease after one
-
eighth
of the Time to Live (TTL) interval has expired.


When half the TTL interval has expired, the WINS client
attempts to refresh its lease with a secondary WINS server.


When a WINS server receives the name refresh request, it sends
the client a name refresh response with a new TTL interval.

Name Release


When a WINS client’s name is no longer in use, the client sends
a message to the WINS server to release the name.


When the WINS server receives the name release request, it
checks its database for the specified name.

Name Query


After a WINS client has registered its NetBIOS name and IP
address with a WINS server, it can communicate with other
hosts by obtaining the IP address of other NetBIOS
-
based
computers from the WINS server.


By default, a WINS client attempts to resolve another host’s
NetBIOS name to an IP address.

WINS Server Configuration


A WINS server requires a computer running Windows 2000
Server; however, the server does not have to be a domain
controller.


A WINS server can include additional configurations.

WINS Client Configuration


A WINS client must be running one of the supported operating
systems.


A WINS client also requires the IP address of a primary WINS
server and optionally, the IP address of a secondary WINS
server.

WINS Installation


The WINS service is not installed as part of the default Windows
2000 Server installation.


After you install the WINS Service, you should configure its
TCP/IP properties so that the computer points to itself.

WINS Snap
-
In

DHCP Server Configuration

Overview of DNS


WINS resolves NetBIOS names to IP addresses, while DNS
resolves IP host names to IP addresses.


IP host names resolved by using DNS or other means provide a
number of benefits.

Domain Namespace

Host Names


Host names refer to specific computers on the Internet or a
private network.


A host name is the leftmost portion of the fully qualified domain
name (FQDN), which describes the exact position of a host
within the domain hierarchy.


DNS uses a host’s FQDN to resolve a name to an IP address.

Domain Naming Guidelines


Limit the number of domain levels.


Use unique names.


Use simple names.


Avoid lengthy domain names.


Use standard DNS characters and Unicode characters.

Zones

Name Servers


A DNS name server stores the zone database file.


Name servers can store data for one zone or multiple zones.


There must be at least one name server for a zone.


A zone can have multiple name servers associated with it.


Multiple name servers provide several advantages.

Introduction to the Name
Resolution Process


Name resolution is the process of resolving names to IP
addresses.


DNS name servers resolve forward and reverse lookup queries.

Forward Lookup Query

Name Server Caching


When a name server is processing a query, it might be required
to send out several queries to find the answer.


When a name server receives a query request, several events
occur.


Caching query results enables the name server to quickly resolve
other queries to the same portion of the domain namespace.

Reverse Lookup Query


A reverse lookup query maps an IP address to a name.


Because the DNS distributed database is indexed by name and
not by IP address, a reverse lookup query would require an
exhaustive search of every domain name.


The in
-
addr.arpa domain is based on IP addresses, not domain
names.

Installing the DNS Service


To implement DNS, you must configure the server and then
install the DNS service.


The DNS server must be configured with a static IP address.


The DNS installation process accomplishes a number of tasks.

The DNS Snap
-
In

Creating Forward Lookup
Zones


A forward lookup zone enables forward lookup queries.


You can configure three types of zones.


Typically, a zone is named after the highest domain in the
hierarchy that the zone encompasses.

Creating Reverse Lookup
Zones


A reverse lookup zone enables reverse lookup queries.


Reverse lookup zones are not required; however, a reverse
lookup zone is required to run troubleshooting tools and to
record a name instead of an IP address in log files.


The zone types are the same as the zone type options available
in creating a forward lookup zone.


Enter your network ID or the name of the reverse lookup zone.

Adding Resource Records


Once you create your zones, you can use the DNS snap
-
in to
add resource records.


When a zone is created, DNS automatically adds two resource
records.


For a list of other types of resource records along with a
description of each type, open the Resource Record Type

dialog box.

Configuring Dynamic DNS


Dynamic updates


DDNS and DHCP

Configuring a DNS Client

Troubleshooting the DNS
Service

You can troubleshoot name servers by using the monitoring and
logging options in the DNS snap
-
in or by using the nslookup
command
-
line utility.