صفحه 1:
Chapter 1
Introduction
صفحه 2:
Uses of Computer Networks
* Business Applications
* Home Applications
* Mobile Users
° Social Issues
صفحه 3:
Business Applications of
Networks
Client
:
A network with two clients and one server.
صفحه 4:
Business Applications of
Networks (2)
Client machine Server machine
Request
© ما(
1١
+ Reply
Client process Server process
The client-server model involves requests and replies.
صفحه 5:
Home Network Applications
٠ Access to remote information
° Person-to-person communication
¢ Interactive entertainment
¢ Electronic commerce
صفحه 6:
Home Network Applications
mae ut
برا “oi
In peer-to-peer system there are no fixed clients and
صفحه 7:
Home Network Applications
(3)
Example
Ordering books on-line
Car manufacturer ordering tires from supplier
Government distributing tax forms electronically
Auctioning second-hand products on-line
File sharing
Full name
Business-to-consumer
Business-to-business
Government-to-consumer
Consumer-to-consumer
Peer-to-peer
Some forms of e-commerce.
Tag
B2c
B2B
6260
02
pap
صفحه 8:
Mobile Network Users
Applications
Desktop computers in offices
A notebook computer used in a hotel room
Networks in older, unwired buildings
Portable office; PDA for store inventory
Mobile
No
Yes
No
Yes
Wireless
No
No
Yes
Yes
Combinations of wireless networks and mobile
computing.
صفحه 9:
Network Hardware
* Local Area Networks
٠ Metropolitan Area Networks
٠ Wide Area Networks
¢ Wireless Networks
¢ Home Networks
¢ Internetworks
صفحه 10:
Broadcast Networks
Types of transmission
technology
¢ Broadcast links
٠ Point-to-point links
صفحه 11:
Broadcast Networks (2)
Interprocessor Processors Example
distance located in same
1m Square meter | Personal area network
10m Room
400m Building Local area network
1 Campus
10km City Metropolitan area network
100 km Country
= Wide area network
4000 km Continent
10,000 km Planet The Internet
Classification of interconnected processors by scale.
صفحه 12:
Local Area Networks
om, &%
۳ یه
(a) (b)
Computer
Two broadcast networks
(a) Bus
(b) Ring
صفحه 13:
Metropolitan Area Networks
“a 2 2 2
Kies. ۳ عه فقة هت
اه 6 هه jaa
ea ge RE ae وت ey
Head end 1
Internet. iz
PI E
k based on cable TV.
A metropolitan area networ
صفحه 14:
Wide Area Networks
Subnet Router
1
Host
LAN
ation between hosts on LANs and the subnet.
Re
صفحه 15:
Wide Area Networks (2)
Receiving host
۱
Packet Router C makes a
choice to forward
packets to E and
not toD
Sending process Receiving process
A stream of packets from sender to receiver.
صفحه 16:
Wireless Networks
Categories of wireless
networks:
° System interconnection
° Wireless LANs
° Wireless WANs
صفحه 17:
Wireless Networks (2)
(a) Bluetooth configuration
(b) Wireless LAN
صفحه 18:
Wireless Networks (3)
Flying router
Portable
computer
One telephone
call per computer
(a) (b)
(a) Individual mobile computers
(b) A flying LAN
صفحه 19:
Home Network Categories
Computers (desktop PC, PDA, shared
peripherals
Entertainment (TV, DVD, VCR, camera,
stereo, MP3)
Telecomm (telephone, cell phone,
intercom, fax)
Appliances (microwave, fridge, clock,
furnace, airco)
Telemetry (utility meter, burglar alarm,
babycam).
صفحه 20:
Network Software
Protocol Hierarchies
Design Issues for the Layers
Connection-Oriented and Connectionless
Services
Service Primitives
The Relationship of Services to Protocols
صفحه 21:
Network Software
Protocol Hierarchies
Host 1 Host 2
Layer 5 protocol
Layers Jo-----SPSES Preteen لع Layer 5
Layer 4 interface f I
Layer 4 protocol
Layer 4 [o=---SYSES Pree {Layers
Ler in| i
Layer 3 protocol
Layers | ات تب ل -[tayers
ی 1
Layer 2 protocol
کم[
ات | 1
Layer 1 protocol
Layer t fx-=--H¥SE I etenet {Layers
Physical medium
Layers, protocols, and interfaces.
صفحه 22:
Protocol Hierarchies (2)
Location 8
[aime
۹ =[ @
[Fae > ل سس مساو
she
0 ا 3
| em
Infomation
موم من
موز
۳
“E>
13
ماو
The philosopher-translator-secretary architecture.
صفحه 23:
Protocol Hierarchies (3)
Layer 5 ۱
موه بو
5 9 2ب تسيل ۳ cel 1
| 1 4 protocol
5 1| MT e------ Lever 4otocol مد «RL =
Layers
protocol
3 (Rly سه |يلة زولا 1 Hs] Me
Layer ۱
protocol
]یدید [te] [Fo]Me] Mate وب [Te] [Fel Ho] Mele
1
Source machine Destination machine
Example information flow supporting virtual
communication in layer 5.
صفحه 24:
Design Issues for the Layers
° Addressing
¢ Error Control
° Flow Control
٠ Multiplexing
٠ Routing
صفحه 25:
Connection-Oriented and
Connectionless Services
Example
Sequence of pages
Remote login
Digitized voice
Electronic junk mail
Registered mail
Database query
service.
Service
Reliable message stream
Reliable byte stream
Unreliable connection
Unreliable datagram
Acknowledged datagram
Request-reply
Six different types o:
Connection-
oriented
Connection-
less
صفحه 26:
Service Primitives
Primitive Meaning
LISTEN Block waiting for an incoming connection
CONNECT Establish a connection with a waiting peer
RECEIVE Block waiting for an incoming message
SEND Send a message to the peer
DISCONNECT | Terminate a connection
Five service primitives for implementing a simple
connection-oriented service.
صفحه 27:
Service Primitives (2)
Glient machine تم ecuedd Server machine
6 2) ACK
يه | م0 3) Request for data a
System |___(4) Reply لس
cals
omer Kerme | Price تايورم Beomet I Keine ۳۳۵ prvers
Packets sent in a simple client-server interaction
on a connection-oriented network.
صفحه 28:
Services to Protocols
Relationship
Layerk+1 Layerk+1
[sone provided by layer k |
Protocol
Layer k [ater nen ne nnn eee ener eee eee بم يي يمي <
۱۵۷۵۲ ۷-1 ۱۵۷۵۲۷1
The relationship between a service and a protocol.
صفحه 29:
Reference Models
The OSI Reference Model
The TCP/IP Reference Model
A Comparison of OSI and TCP/IP
A Critique of the OSI Model and
Protocols
A Critique of the TCP/IP Reference
Model
صفحه 30:
Reference Models
Layer Name of unit
‘exchanged
Application protocol
7 | Application
Application | APDU
roto | |
6 [ Presentation Presentation] PPOU
The OSI 5 [session
reference 1
model. ۰۴ Transpon_| TOU
Se ere
t 0 cloned 1
Session | SPDU
3 [Network تحت Le Network |+|---[ Network | Packet
2 [ Datalink | Data link Data link Datalink | Frame
1 [Physical |=, Physical |~ Physical Physical | Bit
Host A Router Router Host B
Network layer host-router protocol
Data link layer host-router protocol
Physical layer host-router protocol
صفحه 31:
Reference Models (2)
Os! TCPAP
7 Application Application
6 Presentation ( أمعمعام أولل ب
5 ل 7 in the model
4 Transport Transport
3 Network Internet
2 Data link Host-to-network
1 Physical
The TCP/IP reference model.
صفحه 32:
Reference Models (3)
Layer (OSI names)
Application
Transport
Network
Physical +
data link
DNS
LAN
UDP
‘SMTP
Packet
radio
FIP
‘SATNET
TCP
TELNET
ARPANET
a
Protocols
Networks
Protocols and networks in the TCP/IP model initially.
صفحه 33:
Comparing OSI and TCP/IP
Models
Concepts central to the OSI
model
¢ Services
۰ Interfaces
¢ Protocols
صفحه 34:
A Critique of the OSI Model and
Protocols
Why OSI did not take over the
world
٠ Bad timing
° Bad technology
° Bad implementations
° Bad politics
صفحه 35:
Bad Timing
Billion dollar
Research investment
Activity حب
Time —~
The apocalypse of the two elephants.
صفحه 36:
A Critique of the TCP/IP
Reference Model
Problems:
¢ Service, interface, and protocol not
distinguished
٠ Nota general model
٠ Host-to-network “layer” not really a layer
* No mention of physical and data link layers
* Minor protocols deeply entrenched, hard to
replace
صفحه 37:
Hybrid Model
Application layer
Transport layer
Network layer
Data link layer
Physical layer
= py HOR اصن
The hybrid reference model to be used in this book.
صفحه 38:
Example Networks
The Internet
Connection-Oriented Networks:
X.25, Frame Relay, and ATM
Ethernet
Wireless LANs: 802:11
صفحه 39:
The ARPANET
Switching
بح ماو
office
fa) {b)
(a) Structure of the telephone system.
(b) Baran’s proposed distributed switching system.
صفحه 40:
The ARPANET (2)
Host-host protocol Le Host
Host-IMP-
‘Subnet
IMP
The original ARPANET design.
صفحه 41:
The ARPANET (3)
0
Growth of the ARPANET (a) December 1969. (b) July 1970.
(c) March 1971. (d) April 1972. (e) September 1972.
صفحه 42:
NSFNET
© NSF Supercomputer center
@ NSF Midlevel network
© Both
The NSFNET backbone in 1988.
صفحه 43:
Internet Usage
Traditional applications (1970 -
1990)
° E-mail
۰ 5
° Remote login
٠ File transfer
صفحه 44:
Architecture of the Internet
Overview of the Internet.
صفحه 45:
ATM Virtual Circuits
Router Subnet
Sending host Receiving host
wl ۹
Sending process Virtual circuit Receiving process
A virtual circuit.
صفحه 46:
ATM Virtual Circuits (2)
48
User data
An ATM cell.
5
Header
Bytes
صفحه 47:
The ATM Reference Model
CS: Convergence sublayer
SAR: Segmentation and
reassembly sublayer
TC: Transmission convergence
sublayer
PMD: Physical medium
dependent sublayer
Plane management
Layer management
¢
QA
User plane
Upper layers
The ATM reference model.
Physical layer
2 ‘ATM adaptation layer -------
ATM layer
Control plane
Upper layers
cs
SAR
TC ns
PMD.
صفحه 48:
The ATM Reference Model (2)
Osi ۸۲۷ ۸
layer layer sublayer Functionality
Providing the standard interface (convergence)
AAL 5 | ملو
SAR | Segmentation and reassembly
Flow control
Cell header generation/extraction ۳۹
Virtual circui/path management
Cell multiplexing/demultiplexing
Call rate decoupling
Header checksum generation and verification
2 16 Call generation
Packing/unpacking cells from the enclosing envelope
Frame generation
Physical
Bit timing
1 PMD | Physical network access
The ATM layers and sublayers and their functions.
صفحه 49:
cece
hernet.
Ethernet
۴ 8
Transceiver
۳
| مهس
cable =
8 8 ۲ 5
Architecture of the original Et!
Ether
صفحه 50:
Wireless LANs
Base |_To wired network
station|
fi f
dae eu
(a)
(a) Wireless networking with a base station.
(b) Ad hoc networking.
صفحه 51:
Wireless LANs (2)
The range of a single radio may not cover the entire
system.
صفحه 52:
Wireless LANs (3)
3 ‘Ethemet Base station 8
كك a ۳ Portal
8 cell 8
A multicell 802.11 network.
صفحه 53:
Network Standardization
Who’s Who in the Telecommunications
World
Who's Who in the International
Standards World
Who's Who in the Internet Standards
World
صفحه 54:
ITU
٠ Main sectors
¢ Radiocommunications
°* Telecommunications Standardization
¢ Development
° Classes of Members
° National governments
¢ Sector members
٠ Associate members
۰ Regulatory agencies
صفحه 55:
IEEE 802 Standards
Number
802.1 Overview and architecture of LANs
8022 1 | Logical ink control
8023 * | Ethemet
802.4 1 | Token bus (was briefly used in manufacturing plants)
802.5 | Token ring (IBM's entry into the LAN world)
802.6 1 | Dual queue dual bus (early metropolitan area network
02.7 4 | Technical advisory group on broadband technologies
802.8 t | Technical advisory group on fiber optic technologies
802.9 1 | Isochronous LANs (for realtime applications)
802.10 | Virtual LANs and security
802.11" | Wireless LANs
802.12) | Demand priority (Hewlett Packard's AnyLAN)
802.13 _| Unlucky number. Nobody wanted it
] 302.147 | Cable modems (defunct: an industry consortium got there frst)
802.15 * | Personal area networks (Bluetoath)
802.16 * | Broadband wireless
802.17 | Resilient packet ring
The 802 working groups. The important
ones are marked with *. The ones
marked with V are hibernating. The one
يس لمسسم د tt oe
صفحه 56:
Prefix
Kilo
Mega
Giga
Tera
Peta
Exa
Zetta
Yotta
Metric Units
Explicit
1,000
1,000,000
1,000,000,000
1,000,000,000,000
1,000,000,000,000,000
1,000,000,000,000,000,000
4,000,000,000,000,000,000,000
1,000,000,000,000,000,000,000,000
Exp.
103
10°
10°
10
10%
10
102
10
Prefix
milli
micro
nano
pico
femto
ato
zepto
yosto
Explicit
0.001
0.000001
0.000000001
0,000000000001
0.000000000000001
0.0000000000000000001
0.0000000000000000000001
0,0000000000000000000000001
The principal metric prefixes.
Exp.
103
103
10°
10
105
105
0
10