© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public ITE PC v4.0 Chapter 1 1 Communicating over the Network Network Fundamentals – Chapter 2
© 2007 Cisco Systems, Inc. All rights reserved. Cisco PublicITE PC v4.0Chapter 1 1
Communicating over the Network
Network Fundamentals – Chapter 2
ITE PC v4.0Chapter 1 2© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Objectives Describe the structure of a network, including the
devices and media that are necessary for successful communications.
Explain the function of protocols in network communications.
Explain the advantages of using a layered model to describe network functionality.
Describe the role of each layer in two recognized network models: The TCP/IP model and the OSI model.
Describe the importance of addressing and naming schemes in network communications.
ITE PC v4.0Chapter 1 3© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Network Structure Define the elements of communication
–3 common elements of communication• message source- Sender• the channel- Provides the path way to destination• message destination- Receiver
Define a networkdata or information networks capable of carrying many different types of communications (text, voice, video and other types of data
ITE PC v4.0Chapter 1 4© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Network Structure Describe how messages are communicated
Data is sent across a network in small “chunks” called segments
ITE PC v4.0Chapter 1 5© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Multiplexing occurs when the segments of two or more messages can shuffle into each other and share the medium
Segmentation-Networks can more efficiently send message through different routes if necessary. Because Internet is always adjusting routes for efficiency
ITE PC v4.0Chapter 1 6© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Network Structure Define the components of a network–Network components-Path that a message takes from source to destination
• hardware- Laptop, PC, switch or cabling used to connect devices• software- Communication Programs . Email hosting services, and Web hosting services
ITE PC v4.0Chapter 1 7© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Network Structure End Devices and their Role in the Network
–End devices form interface with human network & communications network–Role of end devices:
• client- Request information and services• server- Reply with the requested information• both client and server-
ITE PC v4.0Chapter 1 8© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Example end devices are as follows:
1.Computers, Workstations, Laptops and servers
2.Network Printers
3.Voice over IP phones
4.Cameras
5.PDAs
6.Remote Monitoring stations for weather observation
Host address is a unique physical address used by hosts inside a LAN
When host sends a message to another host it uses the physical address of the destination device
ITE PC v4.0Chapter 1 9© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Network Structure Identify the role of an intermediary device in a data
network and be able to contrast that role with the role of an end device
–Role of an intermediary device–Connect individual hosts to the network and connect multiple networks to form an internetwork
• provides connectivity and ensures data flows across network
ITE PC v4.0Chapter 1 10© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Intermediary Devices
Network access devices- Connect End users to network Ex: Hubs, Switches and Access Points
Internetwork Devices – Connect one network to one or more networks. Ex: Router
Communication Servers- Route services such IPTV and wireless broadband
Modems- Connect users to servers
Security Devices- Secure the network with devices such as Firewalls
ITE PC v4.0Chapter 1 11© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Intermediary Devices perform: 1. Regenerate and retransmits data signals
2. Maintain information about what pathways exist through the network and internetwork
3. Notify other devices of errors
4.Direct data along alternate pathways
5. Classify and direct message according to Qos
6. Permit or deny the flow of data based on security settings
ITE PC v4.0Chapter 1 12© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
ITE PC v4.0Chapter 1 13© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Network Structure Define network media and criteria for making a network
media choiceNetwork media
this is the channel over which a message travels
ITE PC v4.0Chapter 1 14© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Each media uses different methods of encode messages
Encoding messages refers to the way data is converted to patters of electrical, light or electromagnetic energy carried on the medium
ITE PC v4.0Chapter 1 15© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Media – Copper Ex: Twisted Pair, Encoding –Electrical Pulses
Fiber Optic, Glass or plastic Fibers, Light Pulses
Wireless – Connects local users through the air, Electromagnetic waves
Administrator must consider when choosing network media”
1.Distance the media carry the signal
2. Environment on which media works
3. Bandwidth requirements for users
4. Cost of installation
5. Cost of connectors
ITE PC v4.0Chapter 1 16© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Network Types Define Local Area Networks (LANs)- Group of end devices
and users under the control of a common administration- A network serving a home, building or campus is considered a Local Area Network (LAN)
ITE PC v4.0Chapter 1 17© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Network Types Define Wide Area Networks (WANs)- Used to connect
LANs that are located geographically far apart- LANs separated by geographic distance are connected by a network known as a Wide Area Network (WAN)
ITE PC v4.0Chapter 1 18© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Network Types Define the Internet
The internet is defined as aglobal mesh of interconnected networks
ITE PC v4.0Chapter 1 19© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Internetwork- Collection of two or more LANs connected by WANs
Intranet- Closed to Public, Open for employees to browse
ISP also TSPs connect their customers to the Internet. Customer can be a home user, a company or a government Institution
ITE PC v4.0Chapter 1 20© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Network Types Describe network representations
ITE PC v4.0Chapter 1 21© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Network Representations
NIC
Physical Port
Interface
ITE PC v4.0Chapter 1 22© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Function of Protocol in Network Communication The importance of protocols and how they are used to
facilitate communication over data networksA protocol is a set of predetermined rules
ITE PC v4.0Chapter 1 23© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Function of Protocol in Network Communication Explain network protocols
Network protocols are usedto allow devices to communicate successfully
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Function of Protocol in Network Communication
Describe Protocol suites and industry standards
A standard is a process or protocol that has been endorsed by the
networking industry and ratified by a standards organizationIEEE and IETF
ITE PC v4.0Chapter 1 25© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Function of Protocol in Network Communication Define different protocols and how they interact
ITE PC v4.0Chapter 1 26© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
HTTP:Governs the way that a web server and web client interact
Defines the content and formatting of the requests and responses exchanged between the client and server
TCP: Manages individual conversations between web servers and web clients
Divides HTTP messages into smaller pieces called segments
Internetwork Protocol: IP encapsulates segments into packets assigning the address and selects the best path to the destination
Network Access Protocol: Data Link Management and Physical transmission of data on the media
Data Link protocols take the IP packets and format them to be transmitted over the media
ITE PC v4.0Chapter 1 27© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Function of Protocol in Network Communication Technology independent Protocols
-Many diverse types of devices can communicate using the same sets of protocols. This is because protocols specify network functionality, not the underlying technology to support this functionality.
ITE PC v4.0Chapter 1 28© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Layers with TCP/IP and OSI Model Explain the benefits of using a layered model
–Benefits include• assists in protocol design• fosters competition• changes in one layer do not affect other layers• provides a common language
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Layers with TCP/IP and OSI Model Describe TCP/IP Mode
ITE PC v4.0Chapter 1 30© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Layers with TCP/IP and OSI Model Explain protocol data units (PDU) and encapsulation
Each layer adds control information called PDU
ITE PC v4.0Chapter 1 31© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Layers with TCP/IP and OSI Model Describe the Communication Process
Ex: Email
ITE PC v4.0Chapter 1 32© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Layers with TCP/IP and OSI Model Describe the process of sending and receiving
messages
ITE PC v4.0Chapter 1 33© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Layers with TCP/IP and OSI Model Explain protocol and
reference modelsA protocol model provides a model that closely matches the structure of a particular protocol suite.
A reference model provides a common reference for maintaining consistency within all types of network protocols and services.
ITE PC v4.0Chapter 1 34© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Layers with TCP/IP and OSI Model Define OSI
ITE PC v4.0Chapter 1 35© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Layers with TCP/IP and OSI Model Compare OSI and TCP/IP model
ITE PC v4.0Chapter 1 36© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Addressing and Naming Schemes Explain how labels in encapsulation headers are used
to manage communication in data networks
ITE PC v4.0Chapter 1 37© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Addressing and Naming Schemes Describe examples of Ethernet MAC Addresses, IP
Addresses, and TCP/UDP Port numbers
ITE PC v4.0Chapter 1 38© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Addressing and Naming Schemes Explain how labels in encapsulation headers are used
to manage communication in data networks
ITE PC v4.0Chapter 1 39© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Addressing and Naming Schemes Describe how information in the encapsulation header
is used to identify the source and destination processes for data communication
ITE PC v4.0Chapter 1 40© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public
Summary
ITE PC v4.0Chapter 1 41© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public