Network Security and Architecture

Network Security Importance

Essential for public confidence in Internet use, especially for financial transactions

Governments and businesses handling personal data must protect clients' privacy

Security is vital for retaining web users, who might leave without it

Encryption and security devices are used for security

Network Security Limitations

Encryption and firewalls alone may not suffice to protect networks

The need for security and privacy exceeds current architectural capabilities

Efforts are focused on research, development, and tools to address network security weaknesses

Fault-Tolerant Network Architecture

The Internet was initially designed with fault tolerance as a priority

The U.S. Department of Defense (DoD) aimed for a communication system able to withstand infrastructure damage

Circuit-Switched Networks

Early infrastructure was circuit-switched and connection-oriented

Phone operators established temporary, physical circuits for calls to travel between sender and receiver

Technology was connection-oriented as physical disconnections would drop the call, requiring a new call and circuit

Circuit-switched design had flaws as only one phone call occupied each circuit

Introduction to Computer Networking

Computer Networking is like friends with phones texting each other

Computers connect through cables, Wi-Fi, and share files, printers, and internet

This way they share information quickly like friends talking on their phones.

Computer networks consist of nodes like servers, networking hardware, personal computers

Hostnames and network addresses identify devices on a network

Network Definition

A network involves two or more computers connected to share resources like files, folders, printers, and disk drives

A network is a collection of computers or hardware devices connected physically or logically for exchanging information and cooperation

Networking Definition

Networking is designing, implementing, upgrading, managing, and working with networks and network technologies

Communications Principles

Communication is varied and occurs in different environments

Communication relies on protocols or rules, including:

Identifying sender and receiver

Agreeing on a method

Speaking a common language

Setting speed and delivery

Confirming receipt

Successful communication sends the intended message

Data networks require the same basic criteria for successful communication

External Factors in Communication

The pathway quality between sender and recipient is an external factor

With external factors, the number of times the message is redirected can affect the quality of communication

The number of messages being transmitted during communication can also impact external factors

The time allotted for successful communication

Internal Factors in Communication

Message size impacts data networks

Message complexity, and message importance also affect data networks

Delivering a smaller message is more efficient than delivering a bulky message

Network Classifications by Media

Transmission media classifies: Wired (UTP, coaxial & fiber optic cables) and wireless network

Network Classifications by Scale

Network scale classes are LAN, WAN and MAN

Personal Area Network (PAN): Connects devices within 10 meters, such as a computer to its peripherals (keyboard, mouse, printer) or a PDA controlling a hearing aid via Bluetooth

Local Area Network (LAN): Privately-owned networks cover small areas like homes, offices, to share printers with size restrictions to set a time limit

Network Classifications for MAN and WAN

Metropolitan Area Network (MAN): Covers larger geographic than a LAN, from city blocks to cities, and may use channels for moderate-high data rates

A MAN might be a single organization for public utilities that allows 50km interconnection of LANs for modem and wire/cable applications

Wide Area Network (WAN): Covers large areas like a country or continent with communications links across metropolitan, regional, or national boundaries

A WAN utilizes routers and public communications links

Network Classifications Methods

Networks are classified based on management method: Peer-to-Peer and Client Server

Two main network models are used for data exchange and resource sharing that are Client-Server and Peer-to-Peer Networks

Peer-to-Peer Networks

Peer-to-Peer Networks do not differentiate clients from servers

Each node in the network can request and provide services

Peer-to-peer networks typically involve fewer than 12 machines, each with its unique security measures

Each peer-to-peer network consumes and gives resources and the capability for the network to share resources

Client-Server networks see an overload with greater number of active nodes

Peer-to-peer networks are challenging to secure, as each node acts as both a client and a server

Denial of service attacks can occur, and most OS come with software to implement networks

P2P Network Characteristics

Decentralized: Lacks central servers; all devices are equal

Direct communication: Any device sharing file to another

Small-scale networks: Use for home and small offices

Limited security & management: Managed for their own use

P2P Network Examples

Home networks: Share files without the use of central server

File sharing applications: Shared through P2P file-sharing systems

Small business networks: Sharing printers and drivers among a few employees

P2P Network Advantages

Cost effective to not need servers

Easy to set up simple network function

Does not depend on central servers, the network is functional when one device fails

P2P Network Disadvantages

Security is limited where each divide is responsible for their own security leaving it vulnerable

The network is difficult to manage when it grows increasing connections

Devices slow down if the amount of users requesting data is high

Networks: Client-Server

Model for this network is broadly used

Clients and servers are differentiated and servers along with clients are set in place

The centralized server is used to store data which makes its management centralized

The client requests services from the server

Client-Server Characteristics

Centralized control has dedicated servers to manage the network (files, printers, DBs)

A large number of users can scale efficiently

Access managed on each server for better security

Complex set ups require network admin to manage

Client-Server Examples

Within company networks, employees request files from a server that centrally holds it

Email services connect clients to a mail server such as Gmail

Web apps are accesses by users on websites that are centrally hosted

Banking uses centralized banking servers

Client-Server Advantages

Better security is accomplished through centralized control to protect data and control access management

Efficient management to maintain networking performance

Improved scalability can process client requests with proper structure

Higher performing servers process requests faster

Client-Server Disadvantages

Expense to prepare servers for network base

Requires IT experts to maintain/troubleshoot

Network is affected is server experiences complications

Network Topology

Types of network typology are based on connectivity, bus, star, ring

Structure based on wire or the physical

Logical data is defined on how media is accessed when sending data

Bus Topology

The bus topology is simple and low in cost

Cable trunk as the backbone

Only one computer can send messages at a time

Computer only regenerates and listens to data

Ring Topology

Every computer functions as a repeater, boosting signals

Each computer must send the token to send data

More costly

Entire networks fail based on single computer

Star Topology

Each computer must connect to one point via cable

This topology has the cabling, and therefore a higher cost

When the hub is down the entire network is down

Extended Star Topology

Topology joins unique stars to extend the switch/hub

Network coverage area is also extended

Hierarchical/Tree Topology

Root node is at the central of the network

One or more of the roots are connected to other nodes lower in its hierarchy

Mesh Topology

Designed to implemented for high protection or interruption of service

Each host has unique connections to connect with the others

Internet applies many paths to connect, does not use fully meshed topology

Token Passing Topology

Multistation access uses network to have access to computers on its LAN

The electronic token passed around each host controls access

The computer then sends data when the token is received

When the computer does not send data the token is passed to the next host

Network Components

With the computer network comes hardware and software to allow communication where sharing resources takes place

• Network Hardware Components

Within the network, physical devices are used

Send data on computers, laptops, & other servers

Smartphones and tablets

IoT, scanners and printers

• Network, Intermediary Devices

Network, intermediary devices, like routers or switches, manage and direct network traffic

Routers: Connect Networks to the home internet

Switch: Device to connect multiple devices onto a LAN, directing data

Hub: Broadcasts data (inefficient)

Modem: Converts signals for internet access of DSL wires

Extends wifi for wireless networks

Repeater is used to boost the strength/distance

Types of Networks

• VoIP gateways connect types of networks

Transmission media used to transmit data through different types of wires

LANs via etheret

Cable TV on coated cable

Wifi & bluetooth on the radio

Remote controls on IR

Network Software Components

Controls transmission management

Controls communication between devices

Can run peer-to-peer

NOS Operation

Specialized to manage and connect devices

Security, management of files/users

Types of NOS

Windows & Linux for Peer-to-Peer operations

Unix server for centralized control

Network Protocols

Communications follows network protocol which is between devices on the net/

Types of communications are TCP/IP for internet

UDP is faster but streaming is less reliable, used by TCP

Networking Protocols

Standard wired internet relies on Ethernet

WiFi applies 802.11

IP Addresses

Converts name domains for Internet communication

Software Security

Protects for cybersecurity, i.e. anti-virus

Network Services

Network operations support resource sharing

DNS can translates domain names into IP addresses

DHCP assigns devices and is automized

VPNs offers encrypted connections through IPs

• Other Software Safeguards

Security measures must also involve

Firewalls: Monitor Incoming & Outgoing traffic

Proxy Servers: Act as Intermediaries

Safeguards: Management

Wireshark tools finds network trouble

Health server monitors on NAglos

Tools and monitoring and admin of networks happen on SolarWind

Intermediary Components

The components connect printers & other cell phones for security/data transmission

Filter and manage, optimize for traffic

• Networking: Routers

Different networks connecting and directs traffic

Finds best pathway

Routers

Routes data and can function for both LAN & WAN internet

DHCP assigns for IP Adress Protocol

Firewalls protect at every level

Uses for Routers

Can be used to connect offices

Used in large scale securities

Connections to external networks/ISP applications are edge routers

Function of Switches

Connect with the intended recipient

Each switch uses MAC Addresses

How Switches Operate

Efficiency to lessen collision

LAN segmentation done through VLANS

Switches

Can be unmanaged for plug-and-play small networks connectivity

Management allows traffic control

Legacy Device Hub

Basic connections but does not traffic the LAN

Broadcasts info through devices increasing unnecesary traffic

Modern Networks

Creates network congestion

Less secure due to data collection/sending being unintended for receivers

Moderns

Modem is an analog signal

converts devices digital to computer, using cable/phone lines

Types of Network Cables

DSL: Telephone lines

Coaxial: Broadband Internet

Fiber: Fiber Optics/Hi-Speed Internet

Access Points

Wireless access point will extend the network

Can connects devices to network

Has security (WPA encryptions)

Router delivers and manages wireless traffic

Provides a LAN to connect from

Gateways

Acts as a bridge for communication

Transfers data between each network

Routes internally with internet access, allowing interal network transfer

Firewall

Hardware & software security

Monitors pre-defiend network traffic by blocking unauthorized access and data packets

Protects & monitors cyber threat (DDoS attacks)

Types of Networking Firewalls

Equipment through Fortinet

Windows Defender on software

Networking Interface Card

Wired connects to each device

Wifi connections are then allow

NIC Functions

NIC functions include wireless operation between devices to data transmission while supporting different speeds

Assigns code address

Network Addressing

Ensured transmission data through two protocols of mac-ip code

MAC Addresses

Control over the MAC address/physical code

Written in hexadecimal format

Addressing MAC

Unique: no unique device addresses will ever have a similar address code

Set by manufactuer

Delivery of devices within networks and codes

Types of MAC

Unicast is one code one communication

Multicast is a used code for many communication

Broadcast mac transfer data to all devices

Types of IP Addresses

Address assigned to devices for identification in various networks so device can connect to LAN or internets

IP4

Protocol version to assign addresses: example (192.168.1.1), written (192.168.0.1) with few addresses to use

IP6

Protocol version, 2001:0db8:85a3:0000:0000:8a2e:0370:7334 written code, hexadecimal and separated by colons and trillions of data

IPs

Security addressing applies dynamic and static IPs

Assigned privately which needs manual changes or DHCP based on ISP

Data Networks

Network is connected so the data transmits which differentiates the host through subnet

External networks are gateway for IP and are common on routers connecting local internet serversNetwork Security Importance

Essential for public confidence in Internet use, especially for financial transactions

Governments and businesses handling personal data must protect clients' privacy

Security is vital for retaining web users, who might leave without it

Encryption and security devices are used for security

Network Security Limitations

Encryption and firewalls alone may not suffice to protect networks

The need for security and privacy exceeds current architectural capabilities

Efforts are focused on research, development, and tools to address network security weaknesses

Fault-Tolerant Network Architecture

The Internet was initially designed with fault tolerance as a priority

The U.S. Department of Defense (DoD) aimed for a communication system able to withstand infrastructure damage

Circuit-Switched Networks

Early infrastructure was circuit-switched and connection-oriented

Phone operators established temporary, physical circuits for calls to travel between sender and receiver

Technology was connection-oriented as physical disconnections would drop the call, requiring a new call and circuit

Circuit-switched design had flaws as only one phone call occupied each circuit

Introduction to Computer Networking

Computer Networking is like friends with phones texting each other

Computers connect through cables, Wi-Fi, and share files, printers, and internet

This way they share information quickly like friends talking on their phones.

Computer networks consist of nodes like servers, networking hardware, personal computers

Hostnames and network addresses identify devices on a network

Network Definition

A network involves two or more computers connected to share resources like files, folders, printers, and disk drives

A network is a collection of computers or hardware devices connected physically or logically for exchanging information and cooperation

Networking Definition

Networking is designing, implementing, upgrading, managing, and working with networks and network technologies

Communications Principles

Communication is varied and occurs in different environments

Communication relies on protocols or rules, including:

Identifying sender and receiver

Agreeing on a method

Speaking a common language

Setting speed and delivery

Confirming receipt

Successful communication sends the intended message

Data networks require the same basic criteria for successful communication

External Factors in Communication

The pathway quality between sender and recipient is an external factor

With external factors, the number of times the message is redirected can affect the quality of communication

The number of messages being transmitted during communication can also impact external factors

The time allotted for successful communication

Internal Factors in Communication

Message size impacts data networks

Message complexity, and message importance also affect data networks

Delivering a smaller message is more efficient than delivering a bulky message

Network Classifications by Media

Transmission media classifies: Wired (UTP, coaxial & fiber optic cables) and wireless network

Network Classifications by Scale

Network scale classes are LAN, WAN and MAN

Personal Area Network (PAN): Connects devices within 10 meters, such as a computer to its peripherals (keyboard, mouse, printer) or a PDA controlling a hearing aid via Bluetooth

Local Area Network (LAN): Privately-owned networks cover small areas like homes, offices, to share printers with size restrictions to set a time limit

Network Classifications for MAN and WAN

Metropolitan Area Network (MAN): Covers larger geographic than a LAN, from city blocks to cities, and may use channels for moderate-high data rates

A MAN might be a single organization for public utilities that allows 50km interconnection of LANs for modem and wire/cable applications

Wide Area Network (WAN): Covers large areas like a country or continent with communications links across metropolitan, regional, or national boundaries

A WAN utilizes routers and public communications links

Network Classifications Methods

Networks are classified based on management method: Peer-to-Peer and Client Server

Two main network models are used for data exchange and resource sharing that are Client-Server and Peer-to-Peer Networks

Peer-to-Peer Networks

Peer-to-Peer Networks do not differentiate clients from servers

Each node in the network can request and provide services

Peer-to-peer networks typically involve fewer than 12 machines, each with its unique security measures

Each peer-to-peer network consumes and gives resources and the capability for the network to share resources

Client-Server networks see an overload with greater number of active nodes

Peer-to-peer networks are challenging to secure, as each node acts as both a client and a server

Denial of service attacks can occur, and most OS come with software to implement networks

P2P Network Characteristics

Decentralized: Lacks central servers; all devices are equal

Direct communication: Any device sharing file to another

Small-scale networks: Use for home and small offices

Limited security & management: Managed for their own use

P2P Network Examples

Home networks: Share files without the use of central server

File sharing applications: Shared through P2P file-sharing systems

Small business networks: Sharing printers and drivers among a few employees

P2P Network Advantages

Cost effective to not need servers

Easy to set up simple network function

Does not depend on central servers, the network is functional when one device fails

P2P Network Disadvantages

Security is limited where each divide is responsible for their own security leaving it vulnerable

The network is difficult to manage when it grows increasing connections

Devices slow down if the amount of users requesting data is high

Networks: Client-Server

Model for this network is broadly used

Clients and servers are differentiated and servers along with clients are set in place

The centralized server is used to store data which makes its management centralized

The client requests services from the server

Client-Server Characteristics

Centralized control has dedicated servers to manage the network (files, printers, DBs)

A large number of users can scale efficiently

Access managed on each server for better security

Complex set ups require network admin to manage

Client-Server Examples

Within company networks, employees request files from a server that centrally holds it

Email services connect clients to a mail server such as Gmail

Web apps are accesses by users on websites that are centrally hosted

Banking uses centralized banking servers

Client-Server Advantages

Better security is accomplished through centralized control to protect data and control access management

Efficient management to maintain networking performance

Improved scalability can process client requests with proper structure

Higher performing servers process requests faster

Client-Server Disadvantages

Expense to prepare servers for network base

Requires IT experts to maintain/troubleshoot

Network is affected is server experiences complications

Network Topology

Types of network typology are based on connectivity, bus, star, ring

Structure based on wire or the physical

Logical data is defined on how media is accessed when sending data

Bus Topology

The bus topology is simple and low in cost

Cable trunk as the backbone

Only one computer can send messages at a time

Computer only regenerates and listens to data

Ring Topology

Every computer functions as a repeater, boosting signals

Each computer must send the token to send data

More costly

Entire networks fail based on single computer

Star Topology

Each computer must connect to one point via cable

This topology has the cabling, and therefore a higher cost

When the hub is down the entire network is down

Extended Star Topology

Topology joins unique stars to extend the switch/hub

Network coverage area is also extended

Hierarchical/Tree Topology

Root node is at the central of the network

One or more of the roots are connected to other nodes lower in its hierarchy

Mesh Topology

Designed to implemented for high protection or interruption of service

Each host has unique connections to connect with the others

Internet applies many paths to connect, does not use fully meshed topology

Token Passing Topology

Multistation access uses network to have access to computers on its LAN

The electronic token passed around each host controls access

The computer then sends data when the token is received

When the computer does not send data the token is passed to the next host

Network Components

With the computer network comes hardware and software to allow communication where sharing resources takes place

• Network Hardware Components

Within the network, physical devices are used

Send data on computers, laptops, & other servers

Smartphones and tablets

IoT, scanners and printers

• Network, Intermediary Devices

Network, intermediary devices, like routers or switches, manage and direct network traffic

Routers: Connect Networks to the home internet

Switch: Device to connect multiple devices onto a LAN, directing data

Hub: Broadcasts data (inefficient)

Modem: Converts signals for internet access of DSL wires

Extends wifi for wireless networks

Repeater is used to boost the strength/distance

Types of Networks

• VoIP gateways connect types of networks

Transmission media used to transmit data through different types of wires

LANs via etheret

Cable TV on coated cable

Wifi & bluetooth on the radio

Remote controls on IR

Network Software Components

Controls transmission management

Controls communication between devices

Can run peer-to-peer

NOS Operation

Specialized to manage and connect devices

Security, management of files/users

Types of NOS

Windows & Linux for Peer-to-Peer operations

Unix server for centralized control

Network Protocols

Communications follows network protocol which is between devices on the net/

Types of communications are TCP/IP for internet

UDP is faster but streaming is less reliable, used by TCP

Networking Protocols

Standard wired internet relies on Ethernet

WiFi applies 802.11

IP Addresses

Converts name domains for Internet communication

Software Security

Protects for cybersecurity, i.e. anti-virus

Network Services

Network operations support resource sharing

DNS can translates domain names into IP addresses

DHCP assigns devices and is automized

VPNs offers encrypted connections through IPs

• Other Software Safeguards

Security measures must also involve

Firewalls: Monitor Incoming & Outgoing traffic

Proxy Servers: Act as Intermediaries

Safeguards: Management

Wireshark tools finds network trouble

Health server monitors on NAglos

Tools and monitoring and admin of networks happen on SolarWind

Intermediary Components

The components connect printers & other cell phones for security/data transmission

Filter and manage, optimize for traffic

• Networking: Routers

Different networks connecting and directs traffic

Finds best pathway

Routers

Routes data and can function for both LAN & WAN internet

DHCP assigns for IP Adress Protocol

Firewalls protect at every level

Uses for Routers

Can be used to connect offices

Used in large scale securities

Connections to external networks/ISP applications are edge routers

Function of Switches

Connect with the intended recipient

Each switch uses MAC Addresses

How Switches Operate

Efficiency to lessen collision

LAN segmentation done through VLANS

Switches

Can be unmanaged for plug-and-play small networks connectivity

Management allows traffic control

Legacy Device Hub

Basic connections but does not traffic the LAN

Broadcasts info through devices increasing unnecesary traffic

Modern Networks

Creates network congestion

Less secure due to data collection/sending being unintended for receivers

Moderns

Modem is an analog signal

converts devices digital to computer, using cable/phone lines

Types of Network Cables

DSL: Telephone lines

Coaxial: Broadband Internet

Fiber: Fiber Optics/Hi-Speed Internet

Access Points

Wireless access point will extend the network

Can connects devices to network

Has security (WPA encryptions)

Router delivers and manages wireless traffic

Provides a LAN to connect from

Gateways

Acts as a bridge for communication

Transfers data between each network

Routes internally with internet access, allowing interal network transfer

Firewall

Hardware & software security

Monitors pre-defiend network traffic by blocking unauthorized access and data packets

Protects & monitors cyber threat (DDoS attacks)

Types of Networking Firewalls

Equipment through Fortinet

Windows Defender on software

Networking Interface Card

Wired connects to each device

Wifi connections are then allow

NIC Functions

NIC functions include wireless operation between devices to data transmission while supporting different speeds

Assigns code address

Network Addressing

Ensured transmission data through two protocols of mac-ip code

MAC Addresses

Control over the MAC address/physical code

Written in hexadecimal format

Addressing MAC

Unique: no unique device addresses will ever have a similar address code

Set by manufactuer

Delivery of devices within networks and codes

Types of MAC

Unicast is one code one communication

Multicast is a used code for many communication

Broadcast mac transfer data to all devices

Types of IP Addresses

Address assigned to devices for identification in various networks so device can connect to LAN or internets

IP4

Protocol version to assign addresses: example (192.168.1.1), written (192.168.0.1) with few addresses to use

IP6

Protocol version, 2001:0db8:85a3:0000:0000:8a2e:0370:7334 written code, hexadecimal and separated by colons and trillions of data

IPs

Security addressing applies dynamic and static IPs

Assigned privately which needs manual changes or DHCP based on ISP

Data Networks

Network is connected so the data transmits which differentiates the host through subnet

External networks are gateway for IP and are common on routers connecting local internet servers