Introduction to TCP/IP

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

Introduction to TCP/IP

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

What is TCP/IP


T
ransmission
C
ontrol
P
rotocol/
I
nternet
P
rotocol



TCP/IP refers to an entire suite of networking
protocols, developed for use on the Internet



TCP

and
IP

are certainly two of the most important

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

TCP/IP Characteristics


TCP/IP provides the services necessary to
interconnect computers and to interconnect networks,
creating the
Internet


Independence from underlying network topology,
physical network hardware, and OS


Unique IP Address


Universal connectivity throughout the network


Standardize high
-
level protocols

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

TCP/IP Internetworking

Token

Ring

FDDI

Private Nets

and Internet

Router

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

LAN and Devices

LANs are designed to :



Operate within a limited geographic area



Allow multiaccess to high
-
bandwidth media



Control the network privately under local administration



Provide full
-
time connectivity to local services



Connect physically adjacent devices

ATM

Switch

Ethernet

Switch

Bridge

Hub

Router

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

Wide
-
Area Networks and Devices

WANs are designed to :



Operate over geography of telecommunications carriers



Allow access over serial interfaces operating at lower speeds



Control the network subject to regulated public services



Provide full
-
time and part
-
time connectivity



Connect devices separated over wide, even global areas

ATM

Switch

Router

Modem

CSU/DSU

TA/NT1


S

X.25 or

Frame Relay

Switch

Comm.

Server

Multiplexor

stat

mux

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

TCP/IP Networking Software


TCP/IP protocol suites define a set of universal
communication services


Services can be implemented in a standardized
manner in the networking software, normally bundled
with OS

TCP/IP

Comm.

Software

Internet

TCP/IP

Comm.

Software

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

TCP/IP and Internet


1957 USSR sputnik, USA established ARPA


1969 ARPA funded ARPANET


1971 Network with 15 nodes


1974 Cerf/Kahn Protocol


1973 Ethernet (Ph.D Disssertation Bob Metcalfe)


1982/83 TCP/IP as a core protocol


1983 4.2 BSD Unix with TCP/IP from UCB

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

Internet growth

Year #Hosts

69 4

84 1024

87 28174

90 313000

91 617000

92 1.1M

93 2.0M

94 3.8M

95 6.6M

96 12.8M

1/97 16M


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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

Internet Technical Bodies


ISOC
-

Internet Society
.

Professional society to
promote the use of Internet for research and scholar
communication and collaboration


IAB
-

Internet Archtecture Board
.

Technical
oversight and coordination, falls under ISOC



IETF
-

Internet Engineering Task force.

Current
protocols and specifications for standardization.
Meets 3 times a year, organized in working groups


IRTF
-

Internet Research Task force.

Research
oriented for future.

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

Internet Administrations


DDN

-

the USA Defense Data Network is the government
organization that has overall responsibilty for administrating the
Internet


DDN NIC

(Network Information Center)


assigns unigues names and addresses


collects and distributes information about TCP/IP protocols


IANA

Internet Assigned Numbers Authority


assigns valur for network parameters, name of services,
identifiers


NOC

(Network Operations Center)


manages communication links

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

IAB Standard Tracks

RFC

Internet Draft

Proposed
Standard

Draft Standard

Official Standard

Circulated technical documents call
Request For Comments

Revision RFC

protocol specifications should be stable
technically and should have no bugs or
holes.

at least 2 independence and interoparable
implementation that test all specification
funcions

have had significant field use and clear
communinity interest in production use.

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

Protocol Status Levels


All TCP/IP protocol have one of the following five
status levels


Required


Recommended


Elective


Limited use


Not recommended

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

Internet documents


RFC


number with RFC XXXX, more than 1700 nows


updated RFCs are published with ne RFC numbers


not all RFCs describe protocols. not all RFCs are used


ftp://ds.internic.net


STD

(STandDard)


official Internet standard


FYI

(For Your Information)


RFCs series that do not contain protocol specifications

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

Sample Documents


RFC


2030 I D. Mills,
"Simple Network Time Protocol (SNTP)
Version 4 for IPv4, IPv6 and OSI
", 10/30/1996. (Pages=18)
(Format=.txt) (Obsoletes RFC1769)


1879 I B. Manning, "
Class A Subnet Experiment Results and
Recommendations
", 01/15/1996. (Pages=6) (Format=.txt)



FYI


0023
Guide to Network Resource Tool
. EARN Staff. March 1994.
(Format:TXT=235112 bytes) (Also RFC1580)


0028
Netiquette Guidelines. S. Hambridge
. October 1995.
(Format: TXT=46185 bytes) (Also RFC1855)

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

TCP/IP Architectural Layers

Application

Transport

Internet

Network

Physical

Network

Applications

End
-
to
-
end

Services

Routing

Transmission

Network Interface

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

Physical

TCP/IP and OSI

Application

Presentation

Session

Transport

Network

Data Link

Physical

Application

Transport

Internet

Network

TCP/IP

OSI

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

TCP/IP majors protocols

Physical

Application

Transport

Internet

Network

FTP TELNET SMTP TFTP NFS NTP SNMP NNTP

DNS BOOTP DHCP HTTP X
-
windows


TCP UDP

IP

Network Driver Software

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

Communications Protocols


A Communication protocol that provides a data
transfer service can be either
connection
-
oriented

or
connectionless



Connection
-
oriented
--
A connection is generated
before the data is exchanged (e.g. TCP)


Connectionless
--

Try its best to delivery data, no
need to establish connection (e.g. UDP)

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

FTP

Server

Client
-
Server Relationships


One application component,
called
Server
,
provides a well
-

defined services for application
components running, called
client



Clients make a request for a
services by transmitiing data to
the server.



Servers reply by sending data
back to the client



How the server knowns type of
services ?

TELNET

Server

TELNET

Client

FTP

Cleint

FTP

Cleint

FTP

Client

TELNET

Server

TELNET

Client

FTP

Server

FTP

Server

FTP Protocol

FTP Protocol

FTP Protocol

TELNET Protocol

TELNET Protocol

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Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks

CONSYL

Port Assignments


Servers are known by ports number


FTP 20, TELNET 23, SMTP 25, HTTP 80



Port numbers are generally allocated by


0
--
not used


1
-
255
--
Reserved ports for well
-
known services


256
-
1023
--
Other reserved ports


1024
-
65535
--
user
-
defined server ports


Unix store general used port in
/etc/services

Applications

Transport

Network access

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