ccna exploration1 chapter 1: living in a network · pdf fileccna exploration1 chapter 1:...

1© 2004, Cisco Systems, Inc. All rights reserved.

CCNA Exploration1 Chapter 1: Living in a Network Centric World

LOCAL CISCO ACADEMY ELSYS TUINSTRUCTOR: STELA STEFANOVA

PDF created with pdfFactory Pro trial version www.pdffactory.com

http://www.pdffactory.com


Objectives

• Describe how networks impact our daily lives.• Describe the role of data networking in the

human network.• Identify the key components of any data

network.• Identify the opportunities and challenges

posed by converged networks.• Describe the characteristics of network

architectures: fault tolerance, scalability, quality of service and security.

• Install and use IRC clients and a Wiki server.




How Networks Impact Daily Life

Benefits of instantaneous communication and how it supports and improves our lives




How Networks Impact Daily Life

Characteristics and purpose of popular communication media

• Instant messaging

• Weblogs (Blogs)

• Podcasting

• Collaboration Tools




Today’s Popular Communication Tools

Instant messaging (IM) :• is a form of real-time communication

between two or more people based on typed text;

• developed from earlier Internet Relay Chat (IRC) services;

• incorporates features such as file transfer, voice, and video communication;

• sends a written record of the communication (like e-mail);

• is received immediately (e-mail messages is sometimes delayed).





Weblogs (Blogs)

• are web pages that are easy to update and edit;

• give anyone a means to communicate their thoughts to a global audience without technical knowledge of web design;

• there are blogs on nearly every topic one can think of;

• communities of people often form around popular blog authors.




Today’s Popular Communication ToolsWikis:• are web pages that groups of people can edit and

view together;• are a group creation (unlike blogs, that are more of

an individual, personal journals)• can be created in stages, and by anyone, without the

sponsorship of a major commercial enterprise (like blogs)

• public wiki, called Wikipedia - an online encyclopedia- of publicly-contributed topics;

• private organizations and individuals can also build their own wikis to capture collected knowledge on a particular subject;

• many businesses use wikis as their internal collaboration tool;





Podcasting

• is an audio-based medium that originally enabled people to record audio and convert it for use with iPods;

• iPods a small, portable device for audio playback manufactured by Apple;

• allows people to deliver their recordings to a wide audience;

• the audio file is placed on a website (or blog or wiki) where others can download it and play.





Collaboration tools

• give people the opportunity to work together on shared documents;

• without the constraints of location or time zone, individuals connected to a shared system can speak to each other, share text and graphics, and edit documents together;

• with collaboration tools always available, organizations can move quickly to share information and pursue goals.




Networks supporting the way we learn

Using information networks to share and collaborate improves teaching and learning




Networks supporting the way we learnOnline courseware and delivery benefitsCurrent and accurate training materials• Collaboration between vendors, equipment

manufacturers and training providers ensures that the courseware is up-to-date with the latestprocesses and procedures;

• When errors in materials are found and corrected, the new courseware is immediately available to all employees.

Availability of training to a wide audience• Online training is not dependent on travel schedules,

instructor availability or physical class size;• Employees can be given deadlines by which training

is to be completed and the employees can access the courseware when it is convenient.




Networks supporting the way we learnOnline courseware and delivery benefitsConsistent quality of instruction• The quality of the instruction does not vary as it would

if different instructors were delivering an in-person course;

• The online curriculum provides a consistent core of instruction to which instructors can add additional expertise.

Cost reduction• Reducing the cost of travel and the lost time associated

with travel;• It is usually less expensive to revise and update online

courseware than it is to update paper-based material;• Facilities to support in-person training can also be

reduced or eliminated.




Networks supporting the way we workCommunication over a network changes the way we work

teleworkers or telecommuters




Networks supporting the way we learn

Network supports the way we play




Data Networking Role, Components, Challenges

Basic characteristics of communication:

• Rules or agreements are 1st established;• Important information may need to be repeated;• Various modes of communication may impact the effectiveness of getting the message across.




Establishing the Rules

Protocols that govern successful human communication:

• An identified sender and receiver;

• Agreed upon method of communicating (face-to-face, telephone, letter, photograph);

• Common language and grammar;

• Speed and timing of delivery;

• Confirmation or acknowledgementrequirements.




Establishing the Rules




Quality of Communications

External Factors• The external factors affecting communication are related to:

- the complexity of the network;- the number of devices a message must pass through on its route to its final destination.

External factors affecting the success of communication include:• The quality of the pathway between the sender and the

recipient;• The number of times the message has to change form;• The number of times the message has to be redirected or

readdressed;• The number of other messages being transmitted

simultaneously on the communication network;• The amount of time allotted for successful communication.




Quality of Communications

Internal Factors• are related to the nature of the message

itself. Internal factors affecting the successful

communication include:• The size of the message;• The complexity of the message;• The importance of the message.





Role of data networking in communications





• Devices - used to communicate with one another

• Medium - how the devices are connected together

• Messages - information that travels over the medium

• Rules - governs how messages flow across network

Elements of a network:





TCP/IP (Transmission Control Protocol /Internet Protocol)

• is a set of protocols;• industry standard in networking;• is used in home and business networks;• primary protocol of the Internet;• specifies the formatting, addressing and

routing mechanisms that ensure our messages are delivered to the correct recipient.





Multiple services-multiple networks Traditional telephone, radio, television, and computer data networks each have their own individual versions of the four basic network elements.

Converged network

a type of network that can carry voice,video & data over the same network.




Multiple services-multiple networks




Converged network




Network Architecture Characteristics

• Fault tolerance

• Scalability

• Quality of service

• Security

Characteristics of network architecture design:

Network architecture refers to both:

• the technologies that support the infrastructure;

• the programmed services and protocols that move the messages across that infrastructure.





Fault toleranceFault tolerant network:• is one that limits the impact of a hardware or software failure; • can recover quickly when such a failure occurs;• depends on redundant links, or paths, between the source and

destination of a message.

ScalabilityScalable network:• can expand quickly to support new users and applications

without impacting the performance of the service being delivered to existing users;

• the ability of the network to support these new interconnections depends on a hierarchical layered design for the underlying physical infrastructure and logical architecture.





Fault tolerance





Scalability





Quality of service• Voice and live video transmissions require a level

of consistent quality and uninterrupted deliverythat was not necessary for traditional computer applications.

Security• The security and privacy expectations that result

from the use of internetworks to exchange confidential and business critical information exceed what the current architecture can deliver.





Quality of service





Security




Network Architecture CharacteristicsCircuit Switched Connection-oriented Networks




Network Architecture CharacteristicsPacket-switched Connectionless Networks





Characteristics of the Internet scaling for user demand:

• Hierarchy• Common standards• Common protocols




Network Architecture CharacteristicsQuality of Service - factors that necessitate and mechanisms necessary to ensure it




Network Architecture CharacteristicsQoS mechanisms work to ensure quality of

service for applications that require it




Network Architecture CharacteristicsSelection of appropriate QoS strategyfor a given type of traffic





Need of networks security





Basic measures to secure data networks• Ensure confidentiality • Ensure availability• Maintain communication integrity





Ensure confidentiality using:• User authentication• Data encryption

Ensure availability through use of using:• Firewalls• Redundant network architecture• Hardware without a single point of failure

Maintain communication integrity using:• Digital signatures




IRC Clients and Wiki Server

Install and use IRC clients and a Wiki server




Summary



ccna exploration1 chapter 1: living in a network · pdf fileccna exploration1 chapter 1:...

Documents