cisco ccna module 9
TRANSCRIPT
1© 2004, Cisco Systems, Inc. All rights reserved.
Module 9 TCP/IP Protocol Suite and IP
Addressing
222© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idObjectives
333© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idThe TCP/IP Model The Department of Defense (DoD) developed the TCP/IP reference
model to provide a communication network that could continue to function in wartime.
444© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idTCP/IP Applications
555© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idTransport Layer Protocols
• The functions of TCP and UDP
Segment upper-layer application data
666© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idTransport Layer Protocols
TCP is responsible for:• end-to-end
communication • flow control • reliability of data delivery
TCP supports a logical connection between the sending and receiving hosts
777© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idTransport Layer Protocols
888© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idInternet Layer ProtocolsThe IP Protocol is responsible for:• defining packet format and addressing scheme• routing packets to remote hosts• transferring data between the internet layer and the network access
layer
999© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idInternet Layer Protocols
• IP - connectionless, best-effort delivery routing of packets.
• ICMP - control and messaging capabilities.
• ARP - determines the data link layer address for known IP addresses.
• RARP - determines the IP address for a known MAC address.
101010© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idInternet Path Determination
111111© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idQuestion
• Why is IP sometimes referred as an unreliable protocol?
• Is it really unreliable?
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www.pnj.ac.idAnswer
• IP is sometimes referred to as an unreliable protocol.
• This does not mean that IP will not accurately deliver data across a network.
• Calling IP an unreliable protocol simply means that IP does not perform error checking and correction.
• That function is handled by upper layer protocols from the transport or application layers.
131313© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idNetwork Access Protocols
The Network Access Layer is the host-to-network layer of the TCP/IP model.
• Encapsulation of IP packets into frames
• Interface to the physical medium
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www.pnj.ac.id
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www.pnj.ac.idComparing TCP/IP with the OSI Model
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www.pnj.ac.idRouter Connects Two Networks
• A network of networks is called an internet, indicated with the lowercase “i”.
• When referring to the networks that developed from the DoD on which the Worldwide Web (www) runs, the uppercase “I” is used and is called the Internet.
171717© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idRouters Connect Local and Remote Networks
181818© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idUsers See TCP/IP Cloud
191919© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idPhysical Details Hidden from Users
202020© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.id
“Scale-Free Networks”Scientific AmericanMay 2003
The internet somewhere in the N.E. US
212121© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idForwarding Packets—IP address
• A router forwards packets from the originating network to the destination network using the IP protocol.
• The packets must include an identifier for both the source and destination networks.
• Accordingly, every IP address has two parts
– One part identifies the network where the system is connected
– A second part identifies that particular system on the network
222222© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idHost Address
192.168.1.01. 192.168.1.12. 192.168.1.23. 192.168.1.34. 192.168.1.4
192.168.2.01. 192.168.2.12. 192.168.2.23. 192.168.2.34. 192.168.2.4
232323© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idIP Addressing Format
242424© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idConsecutive Decimal and Binary Values
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www.pnj.ac.idTwo Byte (Sixteen Bit Number)
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www.pnj.ac.idTwo Byte (Sixteen Bit Number)
272727© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idOne Byte (Eight Bit Number)
282828© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idDecimal to Binary Conversion
292929© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idTwo Byte (Sixteen Bit Number)
303030© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idBinary to Decimal Conversion
313131© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idNetwork Layer Communication Path
• Routers use IP to make decisions about how to reach a particular destination
323232© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idNetwork and Host Addressing
333333© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idInternet Addresses
• IP address space is hierarchical
• Uses the concept of classes
• Compare this with the flat MAC address space
343434© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idIdentifying Address Classes
• The pattern of High Order Bits defines the class of the network address
353535© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idIP Address Classes
363636© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idAddress Class Prefixes
373737© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idNetwork and Host Division
383838© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idClass A Address
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www.pnj.ac.idClass B Address
404040© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idClass C Address
414141© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idClass D Address Architecture
424242© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idClass E Address Architecture
434343© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idIP Address Range
444444© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idNetwork Address
• Host portion all zeros
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www.pnj.ac.idBroadcast Address
• Host portion all ones
464646© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idNetwork Address
474747© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idUnicast Transmission (to ONE Host only)• Addressed to a specific host
i.e. 176.10.16.1
• Only that host looks at the contents of the packet
484848© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idBroadcast Address (to ALL Hosts)
494949© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idBroadcast Transmission
• All hosts listen for broadcast messages
• Only the host with the appropriate service responds
505050© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idRequired Unique Address• A packet can only be sent out onto the Internet if it has a
unique address
515151© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idPrivate IP Addresses
• You can use these addresses on any private LAN.
• You CANNOT use them on the internet. • Internet routers will block them.
525252© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idUsing Private Addresses in the WAN
•Connecting a network using private addresses to the Internet requires translation of the private addresses to public addresses •This translation process is referred to as Network Address Translation (NAT)
535353© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idIPv4 Address Allocation
545454© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idSubnet Addresses
555555© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idIPv4 and IPv6
565656© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idIPv4 and IPv6 Addresses
575757© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idAssigning IP Addresses
585858© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idTCPIP/IP Configuration for Windows 98
595959© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idIP Address
606060© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idARP/RARP Message Structure
616161© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idBOOTP Message Structure
626262© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idDHCP Message Structure
636363© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idARP Table Entry
646464© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idARP Table Funtions
656565© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idThe ARP Process
666666© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idARP Request
676767© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idProxy ARP Request
686868© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idWhich host has this IP address?
• ARP
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www.pnj.ac.idDefault Gateway
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www.pnj.ac.idSummary
717171© 2004, Cisco Systems, Inc. All rights reserved.
www.pnj.ac.idQuick Reference Subnetting Chart