Transcript IP Address - Salisbury University

Networking
Christina
Angstadt
Karlie Meyer
Kait Sharer

Internet Protocol Address: exclusive number all information technology
devices use which identifies and allows them the ability to communicate
with each other on a computer network
Dynamic IP Address
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Static IP Address
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IP version 4
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IP version 6
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◦ Can change at any time
◦ Issued from a pool of IP addresses allocated by ISP or DCHP Server
◦ Computer automatically gets this number as it logs on to the network
◦ Fixed and never changes
◦ ISP provides a single static IP or a block of static IP’s
◦ Currently used by most network devices
◦ Limited to 4,294,967,296 addresses
◦ Estimated number of unique addresses =
340,282,366,920,938,463,463,374,607,431,768,211,456
◦ Can be written in the following formats:
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1080:0000:0000:0000:0000:0034:0000:417A
1080:0:0:0:0:34:0:417A
1080::34:0:417a
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Domain Name System (DNS): Allows the IP
address to be translated to words
Dynamic Host Configuration Protocol (DHCP):
◦ A computer networking protocol used by hosts to
retrieve IP address assignments and other
configuration information.
◦ Client-server architecture
◦ The client sends a broadcast request for
configuration information. The DHCP server
receives the request and responds with
configuration information from its configuration
database
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Public IP address:
◦ Avoid online bans
◦ ISP may assign you an invalid address due to some
technical glitch in their equipment
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Private IP address:
◦ Accidentally configured an invalid address
◦ Using a malfunctioning router that is providing bad
addresses
◦ Installing a new router and re-configuring your
home network to use its default IP address range
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To change a static IP address, contact the ISP
and work with their technical support to have
them assign a new one
To change a dynamic IP address:
◦ If your computer is directly connected to the
Internet, you can attempt to release and renew the
address using ipconfig or a similar utility
◦ Often, you will need to disconnect your modem
from the Internet for a long period of time (many
hours or a few days) before the ISP will assign a
different dynamic IP address.
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Easier
Static address: directly set a new IP address
on the device
Dynamic Address:
◦ release and renew the DHCP address on the client
Or
◦ set up the router to use a different IP address range
Or
◦ change one or more devices on the network from
dynamic to static addressing
1.
2.
3.
4.
5.
Control Panel
Network
Connections
Find Network
Connection to
Internet (LAC)
Right Click and
select Properties
Click Internet
Protocol (TCP/IP)
item in list
6. Click Properties
Button
7. Click Use the
following IP address:
and enter the IP
address, subnet
mask, and default
gateway information
8. Enter the same info
for DNS servers
9. Click OK until done
All information is
provided by ISP
BUT if you are behind a router it gets more
complicating….
 Static IP address should be assigned to the
router.
• Configuring the router to to not get an IP address
dynamically, but instead you'll enter the IP, gateway,
subnet, and possibly DNS information by hand, using
whatever approach your router uses for configuration.
• Port-forwarding
• Configure it to accept requests on
certain "ports" and direct them to
certain computers on your LAN.
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Bandwidth: the volume of information per
unit of time that a transmission medium (like
an Internet connection) can handle.
Latency: refers to any of several kinds of
delays typically incurred in processing of
network data.
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Low latency network experiences small delay times
High latency connection suffers from long delays
Actual bandwidth is affected by high latencies.
Excessive latency creates bottlenecks that prevent
data from filling the network pipe, thus decreasing
effective bandwidth
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A set of rules which is used by computers to
communicate with each other across a
network governing the syntax, semantics,
and synchronization of communication.
A protocol is a convention or standard that
controls or enables the connection,
communication, and data transfer between
computing endpoints.
Implemented by hardware, software, or a
combination of the two.
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Set of communications protocols used for the
Internet
Two-layer program
Transmission Control Protocol (TCP):
◦ Higher layer
◦ Manages the assembling of a message or file into
smaller packets that are transmitted over the Internet
◦ Messages are received by a TCP layer that reassembles
the packets into the original message
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Internet Protocol (IP):
◦ Lower layer
◦ Handles the address part of each packet so that it gets
to the right destination
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Program that allows applications on different
computers to communicate within a local area
network (LAN).
Two communication modes:
◦ Session mode lets two computers establish a
connection for a "conversation," allows larger
messages to be handled, and provides error
detection and recovery
◦ Datagram mode is "connectionless" messages must
be smaller, and the application is responsible for
error detection and recovery. Also supports the
broadcast of a message to every computer on the
LAN.
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Full-duplex data can be transmitted in both
directions on a signal carrier at the same time
Half-duplex data can be transmitted in both
directions on a signal carrier, but not at the
same time.
Both imply a bidirectional line, or one that
can move data in both directions
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Windows has two modes of operation – Workgroup and
Domain
Workgroup:
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Domain:
◦ Peer-to-peer network, or each computer is sustainable on its own
◦ In order for a user to access resources on another workgroup
computer, that exact user must be setup on the other computer
◦ Workgroups offer little security outside of basic access control.
◦ Workgroups are more than adequate for most small business and
home use
◦ Trusted group of computers that share security, access control
and have data passed down from a centralized domain controller
server or servers
◦ Domain Controllers handle all aspects of granting users
permission to login
◦ Use Active Directory which allows and even more centralized point
for software distribution, user management and computer
controls
◦ Most mid to large businesses will run in Domain mode
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HTTP (Hypertext Transfer Protocol):
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FTP:
◦ Set of rules for transferring files (text, graphic images, sound,
video, and other multimedia files) on the World Wide Web.
◦ Application protocol that runs on top of the TCP/IP suite of
protocols
◦ Web browser is an HTTP client, sending requests to server
machines. When the browser user enters file requests by either
"opening" a Web file (typing in a URL) or clicking on a hypertext
link, the browser builds an HTTP request and sends it to the IP
address indicated by the URL. The HTTP daemon in the
destination server machine receives the request and sends back
the requested file or files associated with the request.
◦ simplest way to exchange files between computers on the Internet
◦ Used to transfer Web page files from their creator to the computer
that acts as their server for everyone on the Internet
◦ Used to download programs and other files to your computer from
other servers.
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POP3 (Post Office Protocol 3):
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IMAP (Internet Message Access Protocol):
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SMTP (Simple Mail Transfer Protocol):
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◦ Client/server protocol in which e-mail is received and held for you
by your Internet server
◦ Built into most popular e-mail products, such as Eudora and
Outlook Express. Also built into the Netscape and Microsoft
Internet Explorer browsers
◦ “Store-and-forward” service
◦ Provides the user more capabilities for retaining e-mail on the
server and for organizing it in folders on the server
◦ POP and IMAP both deal with the receiving of e-mail
◦ Protocol for transferring e-mail across the Internet
You send e-mail with SMTP and a mail handler receives it
on your recipient's behalf. Then the mail is read using POP
or IMAP.
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TELENET:
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HTTPS:
◦ User command and an underlying TCP/IP protocol for
accessing remote computers
◦ An administrator or another user can access someone else's
computer remotely
◦ You log on as a regular user with whatever privileges you
may have been granted to the specific application and data
on that computer.
◦ Telnet is most likely to be used by program developers and
anyone who has a need to use specific applications or data
located at a particular host computer.
◦ Use of Secure Socket Layer (SSL) or Transport Layer Security
(TLS) as a sublayer under regular HTTP application layering
◦ Encrypts and decrypts user page requests as well as the
pages that are returned by the Web server
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LAN (Local Area Network):
◦ Group of computers and associated devices that share a
common communications line or wireless link
◦ Connected devices share the resources of a single
processor or server within a small geographic area
◦ Server has applications and data storage that are shared
in common by multiple computer users. A local area
network may serve as few as two or three users or as
many as thousands of users
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WAN (Wide Area Network):
◦ Geographically dispersed telecommunications network
◦ May be privately owned or rented
◦ Inclusion of public (shared user) networks
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Hub:
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Switch:
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Router:
◦ Place of convergence where data arrives from one or more directions and
is forwarded out in one or more other directions
◦ Place where data comes together
◦ Device that channels incoming data from any of multiple input ports to the
specific output port that will take the data toward its intended destination
◦ One or more switches are used to set up a dedicated though temporary
connection or circuit for an exchange between two or more parties
◦ a switch determines from the physical device (MAC) address in each
incoming message frame which output port to forward it to and out of
◦ A device or, in some cases, software in a computer, that determines the
next network point to which a packet should be forwarded toward its
destination
◦ Connected to at least two networks and decides which way to send each
information packet based on its current understanding of the state of the
networks it is connected to
◦ Often included as part of a network switch
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A virtual private network (VPN) is a network that
uses a public telecommunication infrastructure,
to provide remote offices or individual users with
secure access to their organization's network
The goal of a VPN is to provide the organization
with the same capabilities, but at a much lower
cost
The protocols, by encrypting data at the sending
end and decrypting it at the receiving end, send
the data through a "tunnel" that cannot be
"entered" by data that is not properly encrypted
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Plenum
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PVC
◦ In buildings with computer installations, the plenum space is
often used to house connecting communication cables
◦ Often made of Teflon and is more expensive than ordinary cabling
◦ In the event of fire, its outer material is more resistant to flames
and, when burning, produces less smoke than ordinary cabling
◦ Both twisted pair and coaxial cable are made in plenum cable
versions.
◦ Software-defined logical connection in a network such as a frame
relay network
◦ Feature of frame relay that makes it a highly flexible network
technology is that users can define logical connections and
required bandwidth between end points and let the frame relay
network technology worry about how the physical network is used
to achieve the defined connections and manage the traffic
◦ The end points and a stated bandwidth called a Committed
Information Rate (CIR) constitute a PVC
◦ Multiple PVCs share the same physical paths at the same time
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UTP (Unshielded Twisted Pair):
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STP (Shielded Twisted Pair):
◦ Most common kind of copper telephone wiring
◦ Ordinary copper wire that connects home and many
business computers to the telephone company
◦ Each signal on twisted pair requires both wires
◦ Twisted pair is sometimes installed in two or more pairs,
all within a single cable.
◦ Although twisted pair is often associated with home use,
a higher grade of twisted pair is often used for
horizontal wiring in LAN installations because it is less
expensive than coaxial cable
◦ Special kind of copper telephone wiring used in some
business installations
◦ Twisted pair is enclosed in a shield that functions as a
ground
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Fiber to the home (FTTH):
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Coaxial Cable:
◦ Installation and use of optical fiber from a central point directly to
individual buildings such as residences, apartment buildings and
businesses to provide unprecedented high-speed Internet access.
FTTH dramatically increases the connection speeds available to
computer users
◦ Implementing FTTH on a large scale will be costly because it will
require installation of new cable sets over the "last links" from
existing optical fiber cables to individual users
◦ Copper cable widely installed for use in business and corporation
Ethernet and other types of local area network
◦ “Coaxial" because it includes one physical channel that carries the
signal surrounded (after a layer of insulation) by another
concentric physical channel, both running along the same axis
◦ Outer channel serves as a ground
◦ Can be placed in a single outer sheathing and, with repeaters, can
carry information for a great distance
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RJ45:
◦ Single-line jack for digital transmission over ordinary phone wire, either
untwisted or twisted
◦ Eight pins or positions
◦ Two varieties of RJ-45: keyed and unkeyed
 Keyed has a small bump on its end
 Both jack and plug must match
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RJ11:
◦ Most common telephone jack
◦ Can have six conductors but usually is implemented with four
◦ Likely to be the jack that your household or office phones are plugged into
from the ordinary "untwisted" wire people are most familiar with
◦ Four wires are usually characterized as a red and green pair and a black
and white pair
 Red and green pair typically carry voice or data
 Black and white pair may be used for low-voltage signals such as phone
lights
◦ A computer that uses a dial-up modem to connect to a network is usually
plugged into an RJ-11 jack
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Server:
 Web, ftp, email, application server
◦ Provides service to client(s)
 email exchange
 web / database access
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Client:
 browser, email, online chat
◦ Initiates request for some service
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All communication through server
Clients do not communicate directly
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–
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Maintenance
Security
Centralized server / data
Overload
Centralized server
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No dedicated server
End systems directly communicate
◦ Switch roles of client & server
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–
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More peers = better performance
Shared resources
No Single point of failure
High Bandwidth usage
Security
P2P
Client / Server
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Centralized server
◦ Find IP address of remote party / peer
◦ “controls” communication
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Direct client – client connection
◦ not through server
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Skype
Instant messaging
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High-speed Internet
access
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◦ exceeding 200 Kbps
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“Always On”
More reliable
Wider range of
frequencies
Simultaneous access to
voice & data
communication
◦ splitter
Access limited to
phone line bandwidth
◦ 56 Kbps max
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Initiate connection
Dynamic IP address
Less vulnerable to
attacks
Difficult to download
multimedia files
Less cost
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DSL (Digital Subscriber Line)
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Cable
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Fiber to the Home (FTTH)
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Satellite
◦ existing copper telephone lines
◦ Kbps – Mbps
◦ Coaxial cables
◦ 1.5 Mbps +
◦ Converts data signals to light & sends them through glass
fibers
◦ Speeds exceed DSL / Cable by hundreds of Mbps
◦ Provides wireless broadband to remote areas
◦ 500 Kbps (download) & 80 Kbps (upload)
◦ Extreme weather can disrupt service
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High-speed Internet service via wireless
technology
◦ Radio waves / signals
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Speeds roughly equivalent to wired
broadband access
◦ 1.5 Mbps data rate
Standard
802.11a
802.11b
802.11g
802.11n
Speed
54Mbps
11Mbps
54Mbps (108)
100Mbps (600Mbps)
Range
150ft
300ft
300ft
300ft
Frequency
5GHz
2.4GHz
2.4GHz
2.4-5GHz
Security
Compatibility
Spread Spectrum
method
Mode
SSID, MAC Filtering, WEP, WPA (TKIP), WPA2 (AES)
802.11a
802.11b
802.11g/b
802.11n/g/b
DSSS
DSSS
OFDM
OFDM
Ad Hoc or Infrastructure
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WEP (Wired Equivalent Privacy)
◦ Algorithm used to secure wireless networks
 Authentication
 Data encryption
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WPA (WiFi Protected Access)
◦ Encrypts wireless traffic
 Protects against eavesdropping
◦ More secure than WEP
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Dynamic Host Configuration Protocol
◦ Retrieve IP address assignments
◦ Configuration information
◦ Client / server architecture
 Client broadcast request for configuration info
 Server responds from configuration database
 Configure DHCP
◦ Add new machines to network
 Given unique IP Address
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Wireless technology
Exchanges data over short distances
PANs
Uses frequency-hopping spread spectrum
◦ Transmits data into chunks
◦ 2402-2480 MHz range
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Communicate with up to 7 devices
◦ Mobile phones, laptops, GPA, digital cameras,
printers, PCs, video game consoles
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Network type
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Hardware requirements
◦ DSL, cable, Fiber, etc
◦ Desired speed
◦ Network adapters
 Connect computers to network to communicate
◦ Hubs & switches
 Ethernet
◦ Routers & Access Points
 Share single connection between multiple computers
◦ Modems
 Send / receive information over telephone & cable
◦ Network Cables
 Connect computers & hardware
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provides networked computers with the
ability to share a single connection to the
Internet
If you have multiple computers, you can use
ICS to allow you and others on your local area
network (LAN) to perform different tasks
simultaneously
For example, one person can send and
receive e-mail messages, while another
person downloads a file, and another person
browses the Internet
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Multiple users can gain access to the Internet through a single
connection by using Dial-Up Networking and local networking.
Connected devices receive transparent network configuration
by using Domain Name System (DNS) and Dynamic Host
Configuration Protocol (DHCP) to resolve Internet names
Any IP-attached device can connect, including older Windowsbased clients, non-Windows-based clients, Microsoft Windows
98-based clients, and Microsoft Windows 2000-based clients,
with no additional client software required.
Connected devices and software have comprehensive protocol
support. For example, you can play Internet games without
additional configuration, or you can use Point-to-Point
Tunneling Protocol (PPTP) and Virtual Private Networking (VPN)
to gain access to your corporate network.
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DHCP Allocator - A simplified DHCP service that assigns
the IP address, gateway, and name server on the local
network.
DNS Proxy - Resolves names on behalf of local network
clients and forwards queries.
Network Address Translation (NAT) - Maps a set of
private addresses to a set of public addresses. NAT
tracks private-source IP addresses and publicdestination IP addresses for outbound flows. It changes
the IP address information and edits the required IP
header information dynamically.
Auto-dial - Automatically dials connections.
Application programming interfaces (APIs) - For
configuration, status, and dial control for programs.
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Your ICS network is a type of local area
network that relies on a single computer
called a gateway, through which all other
computers and TCP/IP-capable devices
connect to the Internet.
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The hardware and software needed to set up a home
network includes:
◦ A primary computer, called a gateway, that provides
network connectivity to the Internet. This computer must
be running Windows 98 Second Edition, Windows 2000, or
Windows Me with Internet Connection Sharing enabled.
◦ One or more computers running Windows 95, Windows 98,
Microsoft Windows NT 4.0, Windows 2000, or other TCP-IP
enabled client software.
◦ Devices that are capable of connecting to the Internet.
◦ A network connection device for each computer
◦ .Cabling and hubs, depending on the type of connection
devices you use.
◦ A single modem (or an ISDN or ADSL line) for the entire
network.
◦ Internet browser software and TCP/IP drivers installed on
each device that shares the connection.
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You can enable Internet Connection Sharing
by using the Add/Remove Programs tool in
Windows 98 Second Edition or Windows Me:
◦ Click Start, point to Settings, click Control Panel,
and then double-click Add/Remove Programs.
◦ On the Windows Setup tab, double-click Internet
Tools.
◦ Click to select the Internet Connection Sharing
check box, and then click OK.
◦ Click OK, and then follow the instructions on the
screen to run the Internet Connection Sharing
wizard.
Basic tools:
 Network Diagnostics in Help and Support
◦ Contains detailed information about the network configuration and
the results of automated tests.
 Network Connections folder
◦ Contains information and configuration for all network connections on
the computer. To locate the Network Connections folder, click Start,
click Control Panel, and then click Network and Internet Connections.
 IPConfig command
◦ Displays current TCP/IP network configuration values, updates, or
releases, Dynamic Host Configuration Protocol (DHCP) allocated
leases, and display, register, or flush Domain Name System (DNS)
names.
 Ping command
◦ Sends ICMP Echo Request messages to verify that TCP/IP is configured
correctly and that a TCP/IP host is available.
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Make Sure You Have Correct IP Information:
◦ Make sure you have the correct IP scheme for your
network. This would include the:
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IP Address
Subnet Mask
Default Gateway
DNS Servers
◦ IP Config Command
 Displays current TCP/IP network configuration values,
updates, or releases, Dynamic Host Configuration Protocol
(DHCP) allocated leases, and display, register, or flush
Domain Name System (DNS) names.
 FOR: Win9x - Start / Run / command;
Windows2000/XP/Vista - Start / Run / cmd
◦ Then run IPCONFIG /ALL.
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IP Config Command
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Possible causes for not getting an IP address
assigned are:
◦ Defective cable, network card or port on the router.
Make sure you are using all known working
components.
◦ Your router is not configured for DHCP (which
would automatically be assigning IP addresses).
Basic ping tests:
 Using the command prompt
◦ Try pinging the router's IP address
 e.g. ping 192.168.1.1
◦ If you get a reply, then your connection to the
router is working.
◦ If you don't get a reply, then you need to double
check your network card, cable, port on the router.
You might also see if any other computers on the
network can do the same.
Basic ping tests:
 Try pinging an external site by IP address
◦ e.g. ping 4.2.2.1
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If you get a reply, then you have a connection to
the Internet.
If you don't get a reply, there are several things
you can try:
◦ Double check that the router is connecting to the Internet.
Typically you can access the router through your web
browser and check it's status.
◦ Take the power off your DSL/Cable modem and Router.
Plug the modem back in a wait a minute or so. Plug the
router back in and wait a minute or so. Then restart your
computer.
Basic ping tests:
 Try pinging an external site by Name
◦ e.g. ping www.yahoo.com
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If you get a reply, then you have a connection to
the Internet and DNS is working
If you don't get a reply, there are several things
you can try:
◦ Double check your DNS entries
◦ You many need to use the same DNS IP address that
your ISP or Router is using.
◦ On rare occasions your ISP has problems with their DNS
servers. But that is rare in comparison to misconfigured
computers.
Advanced tools:
 Hostname command
◦ Displays the name of the host computer.
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Nbtstat command
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PathPing command
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Route command
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Tracert command
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◦ Displays the status of current NetBIOS over TCP/IP connections,
updates the NetBIOS name cache, and displays the registered
names and scope ID.
◦ Displays a path of a TCP/IP host and packet losses at each router
along the way.
◦ Displays the IP routing table and adds or deletes IP routes.
◦ Displays the path of a TCP/IP host.
To view the correct command syntax to use with each of
these tools, type -? at a command prompt after the name
of the tool.
Automated troubleshooting
 For most issues that involve Internet connectivity,
start by using the Network Diagnostics tool to
identify the source of the issue. To use Network
Diagnostics, follow these steps:
◦ Click Start, and then click Help and Support.
◦ Click the link to Use Tools to view your computer
information and diagnose problems, and then click
Network Diagnostics in the list on the left.
◦ When you click Scan your system, Network Diagnostics
gathers configuration information and performs
automated troubleshooting of the network connection.
◦ When the process is completed, look for any items that
are marked "FAILED" in red, expand those categories,
and then view the additional details about what the
testing showed.
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Start by rechecking your physical connections
verify that your client's wireless adapter is installed and working
properly
verify that your wireless router's LAN settings are correct
verify your client's TCP/IP settings
Once your client has a valid IP address, use "ping" to verify network
connectivity
If your wireless client still cannot connect, get a valid IP address, or ping
your router, it's time to consider wireless-specific problems
If a matched wireless client and router can "hear" each other but still
cannot connect or exchange traffic, look for a security mismatch
Ensure RADIUS is working
If RADIUS is working but the client's access requests are rejected, look
for an 802.1X Extensible Authentication Protocol (EAP) or user login
problem
If your wireless client connects and pings successfully, but encounters
intermittent network connectivity problems (e.g., some pings work,
some fail), you may be experiencing poor signal strength, RF
interference, or disconnection caused by AP roaming.

Microsoft Support

Bob Cerelli’s Windows Page

Wireless network troubleshooting: Connectivity By
Lisa Phifer
◦ http://support.microsoft.com/kb/314067
◦ http://support.microsoft.com/kb/306126
◦ http://support.microsoft.com/kb/234815
◦ http://www.onecomputerguy.com/networking/troubleshoo
t_internet.htm
◦ http://searchnetworking.techtarget.com/news/article/0,28
9142,sid7_gci945257,00.html

Wikipedia
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Search Networking.net

What it is.com
◦ http://www.wikipedia.org
◦ http://searchnetworking.techtarget.com/
◦ http://whatis.techtarget.com/