Introduction to Technology Infrastructure

Chapter 1

Announcements and Outline

• Syllabus Questions• White Hat Agreement

Class Outline1.Introduction to Networks

1.1 Network Types/Technologies1.2 Layering and Packetization

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1.1 Network Types/Technologies

• How we view a network geographically

• Representing Networks in diagrams

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1.1 Network Types/Technologies

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1.1 Network Types/Technologies

Local Area Networks (LAN)

Wireless Local Area Networks (WLAN)

Backbone

MAN

WAN

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1.2 Network Layers Most Commonly Used Models:

• OSI (Open Systems Interconnection Reference Model)

• Network Model

Protocols & Protocol Data Unit (PDU)

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1.2 Network Layers (Network Model)

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1.2 Network Layers (CCNA TCP/IP Model)

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1.2 Network Layers – Packetization

Packetization is breaking down user data into small segments packaging these segments appropriately so that

they can be delivered and reassembled across the network

9*From Agarwal – Business Data Communications

1.2 Network Layers – 5 Important Data Comm. Tasks

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1.2 Network Layers

APPLICATION LAYER• Software used by the users

Common Examples:

Protocols:

PDU:

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1.2 Network Layers

TRANSPORT LAYER • End to end management

Responsibilities:

(1) Link Applications Layer

(2)Segmenting and Tracking

(3)Session Management

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1.2 Network Layers TRANSPORT LAYER (cont.)

Protocols:

PDU:

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1.2 Network Layers NETWORK LAYER• Decides where the messages should go

Functions:(1)Addressing

(2)Routing

Protocol:PDU:

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1.2 Network Layers

DATA LINK LAYER• Moves messages from one computer to the next

Functions:(1)Controls Hardware(2)Formats Messages(3)Error Checking

Protocol:PDU:

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1.2 Network Layers PHYSICAL LAYER• Hardware that transmits the message

Protocols:

PDU:

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1.2 Network Layers - Summary

Layer #

Layer name

Networking task

Header information

5 ApplicationSpecify user needs User commands

4 Transport Segmentation and reassembly of packets Sequence numbers

3 NetworkIdentifying and locating destination Address

2 Data-linkError control Error check

1 PhysicalSignaling None

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Network Model technologies by layer

Network layer

IP

Transport layer

TCP

Transport layer

UDP

Application layer

HTTP

Application layer

SMTP

Application layer

FTP

Application layer

SSH

Application layer

IM

Application layer

SIP (VoIP)

Application layer

NFS/ SMB (File & printer

sharing)

Data link layer

Ethernet

Data link layer

MPLS

Data link layer

ATM

Data link layer

Frame Relay

Data link layer

Wireless LAN

Physical layer

Manchester encoding(Ethernet)

Physical layer

SONET (Optical fiber)

Physical layer

QAM(Phone modem)

Physical layer

CDMA (Cell phone)

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1.2 Network Layers - Summary

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1.2 Network Layers – Msg Transmission

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1.2 Network Layers

Standards• IEEE (Institute of Electrical and Electronics

Engineering) – develops US standards• Formal Standardization Process• Internet technology standards are publicly

available as Requests For Comment (RFCs) http://www.ietf.org/rfc.html

• Highly recommended standards Email: http://www.ietf.org/rfc/rfc0821.txt HTTP: http://www.ietf.org/rfc/rfc2616.txt TCP: http://www.ietf.org/rfc/rfc0793.txt IP: http://www.ietf.org/rfc/rfc0791.txt TCP/ IP tutorial: http://www.ietf.org/rfc/rfc1180.txt Domain names: http://www.ietf.org/rfc/rfc1034.txt

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Pros and Cons of using Layers

CONS:

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Pros and Cons of using Layers

PROS:

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Recap

1 Network Types

1.1 Network Types• LAN• WLAN• Backbone• WAN

1.2 Network Layers• Network Model• Standards• Pros/Cons

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Thursday

Chapter 2 – Application Layer• Hardware• Software Architecture• Web• Email

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