NETWORK SYSTEMS

3.02 UNDERSTAND NETWORK MANAGEMENT.

Networks and the Internet

Network Admins

Network Types

Data Flow

Internet Speed

Security Risks

COURSE CONTENT

Protect The Data

Learn How Data

Flows

Understand

Media

GOALS

Definition• Is responsible for configuring a network system

and managing its operations.

Responsibilities include:• Network configuration• Network design and supervision • Monitoring and filtering• Maintaining and securing• Updating and backing up

NETWORK ADMINISTRATOR

Network configuration• Is the overall design of a communications

network• Software and hardware are arranged in a way

that allows efficiency in the process of transmitting data across the network.

NETWORK ADMINISTRATOR

Designing, setting up and maintaining networks• Network admin selects and sets up hardware

networks (often cabling done by laborers) • Network admin selects and utilizes network

storage, both client and sever, on a variety of platforms for upgrading and maintaining networks and telecommunications.

NETWORK ADMINISTRATOR

Manages networks using Network Operating Systems• Network Operating System (NOS) is an operating system

that includes special functions for connecting computers and devices into a local-area network.Examples of client-server NOS include:• Novell• Windows• Linux

Examples of NOS that are embedded in network devices and firewalls• Cisco IOS

NOS for peer-to-peer• Windows workgroup• AppleShare

NETWORK ADMINISTRATOR

Monitors the network using monitoring and filtering software

• Networking monitoring software uses TCP (Transmission Control Protocol) ports to monitor and report on network activities and systems availability.

• Network monitoring systems are used to monitor network devices and printers, computer temperature, network interfaces, and disk memory. The software can prevent malicious attacks on a computer.

NETWORK ADMINISTRATOR

Security and analytics• Ensures the security of the network using software that

protects computers from malicious software attacks.• Analyzes the network using system analyzing software

identifies and reports locations where computers are experiencing difficulties like slow downs, viral attacks or hacking.

NETWORK ADMINISTRATOR

Maintaining network operations and software applications, and server backups

• Workstations are often set up to be uniform through the use of ghosting or imaging software. A single computer is configured and the computer’s image is transferred to other computers.

• Back up software and hardware provides a way to recover files.

• Virtual desktops or thin client software can be used to provide the same desktop configuration to groups of users.

• Recommends equipment, software, supplies and materials.

NETWORK ADMINISTRATOR

Network access• Network admin must determine the amount of access given

to users on the network.• Network access involves setting roles, privileges and rights.

• Roles can permit a user to temporarily receive certain rights.

• Rights are permissions to a resource. Rights are typically granted to either users or groups.

• A privilege is often used to reference specific tasks that a user can perform.

• Rights, permissions and privileges impact the ability of users to access directories, files, applications and devices on a network.

NETWORK ADMINISTRATOR

Defining roles• System Administrator or Sys Admin is defined as the

administrator role in a given system. This role creates user accounts and other network objects.

• Network user is the account that gives a user access to a network.

• Application roles are defined for users who have the privileges to use and modify applications, such as databases.

• User roles can be defined for individuals or groups.

NETWORK ADMINISTRATOR

Defining profiles• Profiles contain settings for the network environment,

such as desktop configuration and menu options.• Profiles are used to identify common conditions under

which a user group, identified by roles, can access resources or provide a desktop arrangement.

NETWORK ADMINISTRATOR

Intranet• A private network that facilitates communication

between departments of an organization or business

• Intranets are accessible by employees inside the organization.

• Cannot be accessed from the outside without the use of an extranet

LIMITED NETWORK CONNECTIVITY

Admin

Shipping

Personnel

Extranet• A network that allows limited access from outside

a private network associated with a company• Used for business partners and employees to

conduct business from remote locations• Allows business partners to access data to

speed up shipping or manage services.

LIMITED NETWORK CONNECTIVITY

AdminShippin

g Personnel

HomeExtranet

• Based on data flow• Data flow is the flow of bits of data from one

device on the network to another.• Encapsulation – The creating and formatting of

the data to be sent.• De-encapsulation – The removal of the control

information of the message once it reaches the destination.

INTERNET CONNECTIVITY

• Bandwidth – Theoretical amount of data that can be transmitted across a given medium

• Throughput – The actual amount of data that can be transmitted across a given medium

• Units of Measurement:• Bits per second (bps) = a small text message• Kilobits per second (Kbps) = a text document• Megabits per second (Mbps) = one or two photos• Gigabits per second (Gbps) = a movie

MEASURING INTERNET DATA FLOW

• Estimated bandwidth through different transmission• Dial-up connection with modem – 56 Kbitsps• DSL (digital subscriber line) – 10 Mbitsps• Cable connection – 30 Mbitsps• T1 line – 1.544 Mbitsps

• A T1 line is dedicated to a certain location often reaching speeds higher than DSL or cable.

• Ethernet – 10 Mbitsps• Fast Ethernet – 100 Mbitsps• Fiber optics – 100 Gbitsps• Satelittle – 400 Kbitsps• *all speeds are listed in their max states

MEASURING INTERNET DATA FLOW

• Bandwidth refers to ideal conditions for network speed.

• How fast could you go if you were the only caron the highway?

• Some providers charge extra for overage of bandwidth limits.

• High speed internet users may have their connection reduced when they reach the limit of the connection to help providers ensure that all users have access.

• Internet connections will only travel as fast as your cable will allow.

BANDWIDTH

• Throughput is the actual amount of data that can be transmitted across a given media relative to the restrictions and resistance of the media.

• What if the road wasn’t straight, or there was road construction?

THROUGHPUT

Network Limitations:• Data type• Topology• Congestion• Computer

processing

• A seven layered model used as an educational tool to simplify network communications.

• Let’s look at the first four layers.

OSI MODEL

• Layer 4 is the “hand shake” layer. This layer establishes the type of connection necessary to complete your internet request.

• If you are going to Skype, video chat or audio chat then your connection would be connectionless.

• If you are going to read articles, look at images, play music and videos your connection would connection oriented.

• TCP (transmission control protocol) is a connection oriented service.

• UDP (user datagram protocol) is a connectionless oriented service.

TRANSPORT LAYER

Layer 3 is the network layer.• It provides the routing information of the data.• It handles IP addresses.

NETWORK LAYER

Computer: Can you get to www.google.com?

Router: Is that even on my network? Router: Uh, you’ll need an IP address for that website.

Layer 2 is the data link layer.• It converts the logical data into electronic pulses.• It handles MAC addresses.

DATA LINK LAYER

PC says: User is asking for me to print.PC asks: Who’s the printer?Printer says: I am.PC asks for MAC address and printer replies 0B-5A-01-15-C1.PC says here is the print in bits.

Layer 1 is the data link layer.• It is the physical link between devices on the network.• It is the coaxial, fiber, and utp media connections.

PHYSICAL LAYER

CATEGORIES OF INTERNET SPEED

The speed at which a user can retrieve data from the Internet

DOWNLOAD SPEED

The speed at which a user can send data to a remote location on the Internet

UPLOAD SPEED

The lag, or length of time, that occurs between each point during information transfer

LATENCY

LINKING TO THE INTERNET

To link to the Internet, the user needs to set up service with a company that has a permanent connection and that can provide temporary access to users

INTERNET SERVICE PROVIDER

I S P

To connect to the Internet, a computer must have a unique identifier

INTERNET PROTOCOL ADDRESS

I P ADDRESS

SECURITY RISKS

A computer program that replicates itself. Often with malicious intent to destroy critical system files.

VIRUS

A form of malware that uses the network to spread from host to host

WORM

A standalone, malicious program that gives access from the infected computer to another computer. Often disguised as popular apps or download illegal copies.Sometimes key stroke loggers and unwanted advertisements will be present.

TROJAN HORSE

• The word Botnet is derived from robot and network.• A collection of internet-connected programs

communicating with other similar programs in order to perform tasks. Botnets can be used to send spam or DDos (Distributed Denial of Service attacks).

• A Trojan horse may be the vehicle to breach the security on a computer. After infection the computer would then be organized into a network of bots that can be remotely managed.

BOTNET ATTACKS

An intrusion to the network

Types:• Hacker• Phishing• Malware• Spyware• Adware

UNAUTHORIZED ACCESS

A person who finds and exploits weaknesses of a computer

HACKER

The act of masquerading as a trustworthy website or other entity to acquire user information

PHISHING

Malicious software meant to gain access, disrupt computer operation, or gather sensitive information

MALWARE

A type of malware that collects user information by tracking the habits of users

SPYWARE

Advertising software that automatically generates advertisements

ADWARE

Denial of Service (Dos) or Distributed Denial of Service (DDoS) is an attempt to make a machine or network resource unavailable to its intended users.

DENIAL OF SERVICE

An attempt to use another’s identity to commit a crime

IDENTITY FRAUD

• User awareness and education

• Anti-virus software• Firewalls• Passwords• Authentication

PREVENTION METHODS

User awareness and education• User should remain educated about

computer risks.• Internet resources• Public news networks

USER AWARENESS

• Antivirus software is an application used to prevent infection from risks.

• Commonly, antivirus software updates at regular intervals to guard against newly-created risks.

ANTIVIRUS SOFTWARE

• A firewall is a physical device or application designed to deny incoming or outgoing traffic on a network.

FIREWALLS

• A string of characters that allows access to a computer, interface or system.

• Passwords should be complex, including letters, numbers, and/or special characters.

• Passwords should be kept confidential.• Passwords should be changed regularly and not be

used repeatedly for other applications.

• An alternative that is strongly recommended is to use a passphrase.

PASSWORDS

PASSWORDS AND PHRASES

• The process of verifying that “you are who you say you are”.

• Two-step verification or authentication is available for some services. It adds a section check to make sure of the user’s identity.

• A bank card and a PIN number is a two-step verification system.

AUTHENTICATION