1/59
This is genuinely just human bio please kill me now.
Name | Mastery | Learn | Test | Matching | Spaced |
---|
No study sessions yet.
DOD TCP/IP model - purposes
Standardisation of Network Communication
Reliable Data Transmission
Routing and Adressing
Support for a wide range of Services
Scalability and Flexability
Foundation for modern internet
DOP TCP/IP model - Standardisation of Network Communication
Provides a standardised set of protocols for transmitting data over networks. Ensures that different computer systems, regardless of their hardware and software configurations can communicate effectively.
DOP TCP/IP model - Reliable Data Transmission
Splits data into packets, transmitting them and then reassembling them at the destination, while also handling error checking and correction.
DOP TCP/IP model - Routing and Addressing
The IP component is responsible for addressing and routing packets to their destination across multiple networks. This is crucial for large-scale networks where the data must traverse various types of networks and devices.
DOP TCP/IP model - Support for a wide range of services
Many types of services and applications from file transfers and email to complex systems for command and control.
DOP TCP/IP model - Scalability and flexibility
Designed to scalable and adaptable to a range to network architectures, from small local networks to global communities.
DOP TCP/IP model - Foundation for the modern internet
Laid the groundwork for the modern Internet, using these protocols universally for all forms of digital communications.
Different types of layers in the DOD TCP/IP model
Application
Transport
Internet
Network
DOD TCP/IP model - Application Layer
Role and Functions
Interfaces with user applications, enabling functionalities such as email, file transfers and web browsing.
Key protocols
SMTP, FTP, HTTP, HTTPS, DCHP, DNS
Devices Required
Servers and PC’s
DOD TCP/IP model - Transport Layer
Role and Functions
Manages end-to-end communication, ensuring reliable data transfer for TCP (transition control protocol) and connectionless communication for UDP. Segments and manages data flow.
Key protocols
TCP, UDP
DOD TCP/IP model - Internet Layer
Role and Functions:
Handles logical addressing, routing, packet fragmentation and reassembly. Determines optimal packet routing paths.
Key Protocols:
IPv4, IPv6, ARP, ICMP
Devices:
Routers
DOD TCP/IP model - Network Layer
Role and Functions:
Deals with physical and data link issues. Includes bit transmission, frame synchronisation, error handling and MAC addressing.
OSI Model - Physical Layer
Function:
Handles the physical connection between devices, including bit synchronisation, transmission rate, physical topologies and transmission rates.
Protocols:
Ethernet cables and fiber optics
Devices:
Hubs, Repeaters, Modems, Cables, Network adapters
OSI Model - Data Link Layer
Functions:
Defines the format of data on the network. Provides error detection and correction to ensure packets are free from errors.
Protocols:
Ethernet (802.3), Wi-fi (802.11)PPP, Frame Relay
Devices:
Bridges, Network Interface Cards (NICs), Switches, Wireless access points
OSI Model - Network Layer
Function:
Determines how data is sent to the receiving devices and which route to take. Handles logical addressing, routing and traffic control.
Protocols:
IP, ARP, RARP, ICMP
Devices:
Routers, Layer 3 switches, Firewalls
OSI Model - Transport Layer
Functions:
Manages end-to-end communication, ensuring reliable data transfer for TCP and connectionless communication for UDP. Segments and manages data flow.
Protocols:
TCP, UDP
Devices:
Firewalls and Load balancers
OSI Model - Session Layer
Functions:
Manages sessions between applications. Handles setup, coordination (updating data between different systems/platforms) and termination of conversations between applications.
Protocols:
netBIOS and RPC
Devices:
Gateways/Firewalls
OSI Model - Presentation Layer
Function:
Transforms data to provide a standard interface for the application layer. Handles encryption, compression and translation between data formats.
Protocols:
SSL, TLS, MIME
Devices:
Gateways
OSI Model - Application Layer
Function:
Interacts with end-user software applications (Users interacting with intended software)
Protocols:
HTTP, FTP, SMTP, Telnet
Devices:
Gateways, Proxy Servers
Mnemonic for remembering OSI layers
1 → 7: Please Do Not Throw Sausage Pizza Away
Mnemonic for remembering DoD TCP/IP models
1 → 4: Missing In The Action
What is this?
A wired router
What is this?
A wireless router
What is this?
A switch
What is this?
A W.A.P (Wireless access point)
What is this?
A firewall
What is this?
The internet
What is this?
A server
What is a UTP (Unshielded Twisted Pair)?
TCP/IP Layer:
Network Layer
Function:
Used for connection network devices and transmitting data with less interference. It is a type of copper cable used in many ethernet networks. It consists of wires twisted together to reduce electromagnetic interference.
Technical Details:
Categories: Cat 5e, Cat 6, Cat 6a, Cat 7 (each supporting increasing data rates and bandwidth). Typical use in LAN environment
What is a Fiber Optics?
TCP/IP Layer:
Network Layer
Function:
Transmits data as light pulses, ideal for long distances and high data rates. It is immune to electromagnetic interference.
Technical Details:
Types: Single-mode (long distances and high bandwidth) and multimode (short distances and less bandwidth).
Standards: OS1, OS2 (single mode); OM1, OM2, OM3, OM4, OM5 (multiple modes)
What is the meaning of Wireless as a network component?
TCP/IP Layer:
Network Layer
Function:
Uses electromagnetic waves to transmit data, allowing for mobile connections and infrastructure flexibility. It includes radio signals/infrared signals to transmit data across air and no physical wires.
Technical Details:
Frequencies: 2.4 GHz (wider coverage, slower speed), 5 GHz (faster speed, shorter range).
Standards: IEEE 802.11a/b/g/n/ac/ax
What is a Router?
TCP/IP Layer:
Internet Layer
Function:
Directs data packets between networks based on IP addresses, managic traffic within interconnected networks. It examines the destination IP address of a pocket and determines the best route for it and forwards it accordingly.
Technical Details:
Routing Protocols: OSPF, BGP, EIGRP. Capable of layer 3 switching, QOS, IPv4 and IPv6 support.
What is a Switch?
TCP/IP Layer:
Network Layer
Function:
Connects devices on the same network segment, using MAC addresses to send data packets directly to devices, reducing unnecessary traffic. It is used to connect devices within the same network segment. A switch can identify which device the data needs to be sent to using MAC addresses.
Technical Details:
Types: Managed (configurable options), unmanaged (plug and play), PoE (Power over Ethernet).
Standards: IEEE 802.3 (Ethernet), IEEE 802.1D (STP), IEEE 802.1Q (VLAN)
What is a Wireless Access Point (WAP)?
TCP/IP Layer:
Network Layer
Function:
Connects wireless clients to a wired network, extending user mobility and network availability. It bridges the gap between a wired network and wireless clients.
Technical Details:
Modes: Bridge, Repeater, Client mode. Supports security standards like WEP, WPA, WPA2.
What is a Firewall?
TCP/IP Layer:
Internet Layer
Function:
Monitors and controls incoming and outgoing network traffic based on security rules, blocking unauthorised access. It can operate at multiple layers and essentially provides a barrier between a secure internal network and the internet.
Technical Details:
Types: Hardware (stand-alone unit), software (program on computer), UTM (Unified Threat Management).
Features: Packet filtering, stateful inspection, proxy services and VPN supports.
What is a Gateway?
TCP/IP Layer:
Internet Layer
Function:
Provides a point of access between different networks, often using different protocols and allows networked devices to communicate. Gateways are crucial for protocol conversation, data format transformation and routing between different network architectures like between a corporate network and the internet.
Technical Details:
N/A
Packet Architecture - Data
Refers to the application-level content that needs to be transmitted across a network, such as files, emails or web pages and is process at the Application Layer of the OSI model and is the actual user-generated content.
Packet Architecture - Segments
Units used at the Transport Layer and includes essential control information and manages the data into manageable chunks that facilitate efficient and secure data transmission.
Packet Architecture - Packets
Operate at the Network Layer and are essential for delivering segments across different networks and subnetworks and routing decisions are made based on the information in the packet headers.
Packet Architecture - Frames
Used at Data Link and ensures packets are delivered over a single link node to another.
Packet Architecture - Bits
Smallest units of data represented by binary digits (0 or 1). Grouped together to form all higher-level structures.
Role of IP Addresses
Identification
Location Addressing
Role of Subnet Masks
Network Partitioning (Separates the network or street for example, to the host or house)
Traffic Routing to help routers to determine whether the destination IP is in a local network or outside of it.
MAC Address and Layer 2 Switching
Unique identifier which does not change no matter which network you are connected to
Switches operate at Layer 2 and use MAC addresses to redirect packets within LAN segments.
IP Address and Layer 3 Routing
Every device has an IP address to identify the device on the network
Routers operate at this layer and use IP addresses to determine the best path for forwarding these packets.
TCP vs UDP
• TCP (Transmission Control Protocol): Provides reliable, ordered, and error-checked delivery of a stream of packets on the network. Uses acknowledgments and retransmissions to ensure complete data transfer.
• UDP: Faster, simpler, and does not guarantee message delivery. Best used for video streaming, gaming, and live broadcasts where speed is crucial, and loss is tolerable.
Reliability between TCP and UDP
TCP:
Reliable (guarantees delivery)
UDP:
Unreliable (does not guarantee delivery)
Speed between TCP and UDP
TCP:
Slower due to setup and management.
UDP:
Faster due to minimal overhead
Use Cases between TCP and UDP
TCP:
Web browsing, email and file transfers
UDP:
Streaming, online gaming and VoIP
Use Cases between TCP and UDP
TCP:
Data → Segment → Packet → Frame → Bits
UDP:
Data → Datagram → Packet → Frame → Bits
IPv4 vs IPv6 - Address Length
IPv4:
32-bit
IPv6:
128-bit
IPv4 vs IPv6 - Address Format
IPv4:
Displayed as a dotted decimal (e.g., 192.168.1.1). Each number can be from 0 to 255.
IPv6:
Displayed in Hexadecimal
IPv4 vs IPv6 - Security
IPv4:
Initially did not integrate encryption and authentication
IPv6:
Has IPsec security built into the protocol, ensuring a higher level of security.
IPv4 vs IPv6 - Configuration
IPv4:
Requires manual or DHCP
IPv6:
Stateless address autoconfiguration (SLAAC) or DHCPv6
Public vs Private IP addresses - Definition and IP range
Private IP Addresses:
IP addresses used within a single private network. Not routable on the global internet.
10.0.0.0 to 10.255.255.255 (10/8 prefix) OR 172.16.0.0 to 172.31.255.255 (172.16/12 prefix) OR 192.168.0.0 to 192.168.255.255 (192.168/16 prefix)
Public IP Addresses:
Unique IP addresses used across the entire internet. Routable globally.
No specific ranges; each IP is unique on the internet.
Subnetting
Divides a network into smaller networks (subnets) and for values:
Class A: 0.0.0.0 to 127.255.255.255 - the subnet is 255.0.0.0
Class B: 128.0.0.0 to 191.255.255.255 - the subnet is 255.255.0.0
Class C: 192.0.0.0 to 223.255.255.255 - the subnet is 255.255.255.0
CIDR Notation
Determine the size of the network
Based on the size you need to calculate how many bits are needed. For example if you have 4 subnets, you need at least 2 bits (2² = 4 subnets). To have 254 hosts, you need 8 bits (2^8 - 2 = 254 subnets)
Divide the network
Remember, 2 addresses are unusable as one is the network address and the other is the broadcast address.
Network Performance
Bandwidth: The maximum rate at which data can be transmitted over a network connection. Higher bandwidth allows more data to be transmitted in a given time, leading to faster transmission speeds.
Network Design: Encompasses the overall architecture of a network, including the hardware used and the protocols in place. Efficient network design can optimise data flow.
Data Collisions: Occur when two or more devices attempt to send a packet across a network segment at the same time but using a Collision Detection system helps.
Excess Broadcast Traffic: Refers to the network traffic that is sent to all the nodes on the network and excessive broadcast traffic can consume a lot of bandwidth leading to network slowdowns.
Network Performance Management and Troubleshooting - Ping
Function:
Sends ICMP echo requests to a target host to measure the availability and round trip time of messages
Use:
Primarily used to check if a device is reachable across a network and to measure how long it takes data to travel to and from the device
Network Performance Management and Troubleshooting - Traceroute
Function:
Traces the path data packets take from the source to the destination. It provides the sequence of hops that the packet travels, identifying where delays or drops occur.
Use:
Useful for pinpointing where data paths are inefficient or where data is getting lost.