TLE ❤️
Hub - just a connector that connects the wires coming from different sides. There is no signal processing or regeneration.
TYPES OF HUB:
Passive Hubs - connects nodes in a star configuration by collecting wiring from nodes.
Active Hubs - amplify and regenerate the incoming electrical signals before broadcasting them.
Intelligent Hubs - provide additional network management facilities.
Switch - a point-to-point communication device. It operates at the data link layer of OSI model. It uses switching table to find out the correct destination
TYPES OF SWITCH
Unmanaged Switch - These are inexpensive switches commonly used in home networks and small businesses.
Managed Switch - These are costly switches that are used in organisations with large and complex networks
LAN Switch - Local Area Network (LAN) switches connects devices in the internal LAN of an organization. They are also referred as Ethernet switches or data switches.
PoE Switch - combine data and power transmission over the same cable so that devices connected to it can receive both electricity
Router - multiport devices and more sophisticated as compared to repeaters and bridges.
Routing tables are of two types
Static Routing Table - Here, the routes are fed manually and are not refreshed automatically. It is suitable for small networks containing 2-3 routers.
Dynamic Routing Table - Here, the router communicates with other routers using routing protocols to determine the available routes. It is suited for larger networks having large number of routers
TYPES OF ROUTERS
Wireless Router - They provide WiFi connection WiFi devices like laptops, smartphones etc.
Broadband Routers - They are used to connect to the Internet through telephone and to use voice over
Core Routers - They can route data packets within a given network, but cannot route the packets between the networks
Edge Routers - They are low-capacity routers placed at the periphery of the networks.
Brouters - Brouters are specialised routers that can provide the functionalities of bridges as well. Like a bridge, brouters help to transfer data between networks
OSI Model - describes seven layers that computer systems use to communicate over a network.
Application Layer - used by end-user software such as web browsers and email clients. It provides protocols that allow software to send and receive information and present meaningful data to users.
Presentation Layer - It defines how two devices should encode, encrypt, and compress data so it is received correctly on the other end
Session Layer - It is responsible for opening sessions, ensuring they remain open and functional while data is being transferred, and closing them when communication ends.
Transport Layer - takes data transferred in the session layer and breaks it into "segments" on the transmitting end. It is responsible for reassembling the segments on the receiving end
Network Layer - One is breaking up segments into network packets, and reassembling the packets on the receiving end. The other is routing packets
Data Link Layer - establishes and terminates a connection between two physically-connected nodes on a network. It breaks up packets into frames and sends them from source to destination
Physical Layer - is responsible for the physical cable or wireless connection between network nodes.
NETWORK PROTOCOLS - enable the exchange of information across the internet and work behind the scenes so effectively
Address Resolution Protocol (ARP)
- ARP translates IP addresses to MAC addresses and vice versa so LAN endpoints can communicate with one another.
- MEDIUM ACCESS CONTROL ADDRESS (MAC ADDRESS) - a device's physical hardware number are 12 hexadecimal digits split into six pairs.
Border Gateway Protocol (BGP)
- one or multiple networks run by a single organization or provider -- and connect to different networks.
Domain name system (DNS)
- database that includes a website's domain name and its corresponding IP addresses
Dynamic Host Configuration Protocol (DHCP)
- assigns IP addresses to network endpoints so they can communicate with other network endpoints over IP.
File Transfer Protocol (FTP)
- which a client requests a file and the server supplies it. FTP runs over TCP/IP a suite of communications protocols
Hypertext Transfer Protocol (HTTP)
- primarily works over web browsers and is commonly recognizable for most users. When a user enters a website domain and aims to access it, HTTP provides the access.
Internet Protocol (IP)
- When users send and receive data from their device, the data gets spliced into packets.
Open Shortest Path First (OSPF)
- works with IP to send packets to their destinations.
Simple Mail Transfer Protocol (SMTP)
- the most popular email protocol, is part of the TCP/IP suite and controls how email clients send users' email messages.
Transmission Control Protocol (TCP)
- arranges packets in order so IP can deliver them.
User Datagram Protocol (UDP)
- also works with IP to transmit time-sensitive data. UDP enables low-latency data transmissions between internet applications
IP ADDRESS
- is the unique identifying number assigned to every device connected to the internet
Public IP Address
- or external-facing IP address, applies to the main device people use to connect their business or home internet network to their internet service provider (ISP).
Private IP Address
- internal-facing IP address, is assigned by an office or home intranet (or local area network) to devices, or by the internet service provider (ISP).
Static IP Address
- All public and private addresses are defined as static or dynamic.
Dynamic IP Address
- automatically assigned to a network when a router is set up. The Dynamic Host Configuration Protocol (DHCP) assigns the distribution of this dynamic set of IP addresses.