Objectives
• Discuss the origins of TCP/IP
• Understand the different classes of IP
addresses
• Configure and verify IP addresses
• Subdivide an IP network
• Identify and discuss the different layer
functions of TCP/IP
Objectives (continued)
• Describe the functions performed by
protocols in the TCP/IP protocol suite,
including ICMP, UDP, TCP, ARP, and
RARP
• Use ping and trace and describe their
functions
• Understand advanced routing concepts
such as CIDR, summarization, and VLSM
Origins Of TCP/IP
• United States Department of Defense (DoD)
– Advanced Research Projects Agency (ARPA)
– Create a WAN to survive an nuclear attack
• Advanced Research Projects Agency Network
(ARPANET)
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–
University of California at Santa Barbara (UCSB)
University of California at Los Angeles (UCLA)
Stanford Research Institute
University of Utah
Overview Of The TCP/IP Protocol
Suite
• Application Layer
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File Transfer Protocol (FTP)
Trivial File Transfer Protocol (TFTP)
Network File System (NFS)
Simple Mail Transfer Protocol (SMTP)
Telnet
rlogin
Simple Network Management Protocol (SNMP)
Domain Name System (DNS)
Hypertext Transfer Protocol (HTTP)
Overview Of The TCP/IP Protocol
Suite (continued)
• Transport Layer
– Ports
• Well Known Port numbers
– TCP three-way handshake
• Initial sequence numbers
• Expectational acknowledgement
• Reset packet (RST)
– TCP sliding windows
• Flow control with sliding windows, buffering,
congestion avoidance
Overview Of The TCP/IP Protocol
Suite (continued)
• Internetwork Layer
– Internet Protocol (IP)
• IPv4 and IPv6
– Internet Control Message Protocol (ICMP)
• Echo request, echo reply, and TTL
– Address Resolution Protocol (ARP)
• ARP table, ARP request, ARP reply, and TTL
– Reverse Address Resolution Protocol (RARP)
• RARP server and RARP client
Overview Of The TCP/IP Protocol
Suite (continued)
• Network Interface Layer
– Combines OSI Physical and Data Link layers
– MAC addresses
– Network card drivers
– Specific physical interfaces
Ping Utility
Ping Utility (continued)
Ping Utility (continued)
The Trace Utility
IP Addressing
• MAC to IP address translation
• IP classes
– Internet Assigned Numbers Authority (IANA)
– American Registry of Internet Numbers (ARIN)
– Internet Corporation for Assigned Names and
Numbers (ICANN)
– Class A
– Class B
– Class C
– Class D
– Class E
– Private IP ranges
IP Addressing (continued)
IP Addressing (continued)
IP Addressing (continued)
IP Addressing (continued)
IP Addressing (continued)
Subnet Addressing
• Default class subnet masks
– Class A subnet mask is 255.0.0.0
11111111.00000000.00000000.00000000
– Class B subnet mask is 255.255.0.0
11111111.11111111.00000000.00000000
– Class C subnet mask is 255.255.255.0
11111111.11111111.11111111.00000000
• Boolean ANDing operation
• Subnet addresses
• Broadcast addresses
Broadcast Types
• Flooded broadcasts
– 255.255.255.255
• Directed broadcast
– 129.30.255.255
Subdividing IP Classes
Subnet Masking
Subnet Masking (continued)
Subnet Masking (continued)
Learning To Subnet
Learning To Subnet
(continued)
• Breakdown of 255.255.255.244 subnet mask
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0 (binary 00000000) — unusable
32 (binary 00100000)
64 (binary 01000000)
96 (binary 01100000)
128 (binary 10000000)
160 (binary 10100000)
192 (binary 11000000)
224 (binary 11100000) — unusable
Learning To Subnet
(continued)
Learning To Subnet
(continued)
Subnetting Formulas
• 2y – 2 = # of usable subnets (where y is
the number of bits borrowed)
• 2x – 2 = # of usable hosts per subnet
(where x is the number of bits remaining in
the host field after borrowing)
Subnetting Formulas
(continued)
Subnetting Formulas
(continued)
CIDR
• Classless Inter-Domain Routing (CIDR)
• Developed to slow the exhaustion of IP
Addresses
• Provide efficient use of IP addresses and
address ranges
• Subnetting and supernetting
Summarization
• Also known as route aggregation
• Move subnet mask bits left of the default
boundary
• Combine several default class networks
Variable Length Subnet
Masks
Variable Length Subnet Masks
(continued)
Variable Length Subnet Masks
(continued)
IPv4 Versus IPv6
• Internet Protocol version 4 is the most
widely used
– 32-bit structure
– 232 available addresses
• Internet Protocol version 6 is not common
but used
– 128-bit structure
– 2128 available addresses
Understanding Packet
Transmission
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•
•
•
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Routers on the network
Network to network
Dynamic or static tables
Transmitting packets to remote segments
Routing packets
Understanding Packet
Transmission (continued)
Understanding Packet
Transmission (continued)
Understanding Packet
Transmission (continued)
Understanding Packet Transmission
(continued)
Working With Hexadecimal Numbers
Summary
• TCP/IP is more than just the Transmission Control
Protocol/Internet Protocol; it is an entire suite of
protocols that provides data transportation,
management, and diagnostic capabilities for networks
that use it
• TCP/IP was started by the Defense Advanced Research
Projects Agency (DARPA)
• That group was charged with developing a national
communication system that could survive a nuclear war
• Later, its network, ARPANET, was turned over to the
public, especially universities
• From there, the Internet grew into what it is today, a large
worldwide commerce and communications network
Summary (continued)
• TCP/IP maps to a four-layer network model: Application,
Transport, Internetwork, and Network Interface
• The Application layer in the TCP/IP model covers the
Application, Presentation, and Session layers of the OSI
reference model
• TCP/IP Transport layer maps directly to the OSI Transport
layer
• The Internetwork layer of the TCP/IP model maps directly to
the Network layer of the OSI model
• Network Interface layer of the TCP/IP model is equivalent to
the Data Link and Physical layers of the OSI model
Summary (continued)
• The TCP and UDP protocols reside at the Transport
layer of the TCP/IP networking Model
• UDP is an unreliable and connectionless
communications protocol that does not guarantee packet
delivery
• TCP is a reliable and connection-oriented protocol that
guarantees packet delivery
• TCP uses a three-way handshake to establish a
communications link between two points before data
transfer
• TCP also uses a sliding window to control the flow of
packets and the number of acknowledgments between
the two hosts
Summary (continued)
• Both TCP and UDP use port numbers from 1 to 65,535
to establish their communications between two points
• Ports with numbers 1023 and under are Well Known Port
numbers, as defined in RFC 1700
• These ports describe common Internet services that
hosts can use to contact public servers for specific types
of services, such as Web, FTP, and telnet
• The Internet Protocol (IP) resides at the Internetwork
layer, it provides the logical address that can be passed
through a router
• The subnet mask allows networks to be divided into
subnetworks
Summary (continued)
• You can use the ping utility with IP and ICMP to
diagnose and troubleshoot network connections
• Use the trace utility with IP to determine all the
hops that a packet makes along its path to a
remote TCP/IP host
• Address Resolution Protocol (ARP) and Reverse
ARP (RARP) reside in the Internetwork layer
• These protocols allow the TCP/IP host to map
the IP address to a MAC address
Summary (continued)
• The MAC address is the final leg of communication
between hosts
• Packets are transmitted via the MAC address to the
destination host once the packets arrive at the
destination network or subnetwork
• The Internet Corporation for Assigned Names and
Numbers (ICANN) and the American Registry of Internet
Numbers (ARIN) work together to subdivide and issue
addresses for Internet clients
• Three classes of addresses (A, B, and C) are available
to organizations
• Class A addresses are for governments worldwide
Summary (continued)
• Class B addresses are assigned to medium to large
companies and universities
• Class C addresses are assigned to organizations and
people who require an IP address but do not meet the
criteria to have a Class A or B address
• Class D addresses are used for multicasting information
• Multicasting allows anyone with the correct setup to
broadcast a simultaneous transmission to multiple
computers
• Class E addresses are used for experimentation and
research
Summary (continued)
• The subnet mask divides the network portion of
the IP address from the host portion of the
address
• The network or subnetwork IP address must
always have zeros for the host identifier portion
• IP addresses that identify TCP/IP hosts must be
nonzero in the host portion
• When the host portion of an IP address is all
binary ones, the address is a broadcast address
Summary (continued)
• Routing tables can be created manually and
dynamically
• Network administrators manually create static
routing tables
• A manual table requires more administrative
overhead but gives the administrator greater
control over the routing process
• Dynamic updates are provided through routing
protocols
• The routing protocols allow the routers to be
updated automatically
Summary (continued)
• Advanced routing protocols such as RIP version
2, OSPF, and EIGRP support variable length
subnet masking (VLSM)
• VLSM allows network administrators to better
allocate their IP address space by using different
subnet masks on their subnetworks
• Classful routing protocols such as RIP version 1
and IGRP do not support VLSM
• They require the same subnet mask on every
subnet
Summary (continued)
• IPv6 is the latest version of IP addressing
• Unlike the 32-bit IPv4 addresses that are
in use today on most networks, IPv6
addresses are 128 bits long and are
expressed in hexadecimal
• It is expected that vendors and networkers
will slowly convert to IPv6 in the next
several years
Summary (continued)
• The hexadecimal numbering system is also
known as base 16 because there are 16
available numerals
• The numerals include all of the numbers 0–9 as
well as the letters A–F
• For example, the letter A represents the decimal
number 10 and the letter F represents the
decimal number 15
• Hexadecimal numbers are found in MAC
addresses and IPv6 addresses, and are often
used in computer and networking applications