Before learning anything you needs to learn the basic vocabulary of a subject you are trying to master. This way when reading the rest of the documentation you have a basic understanding of key concepts. A added benefit is you also know you can look back at this section to refresh you memory if a concepts confuses you.

• Default Gateway - The device that passes traffic from the local subnet to devices on other subnets.
• Subnet Mask - a number that defines a range of IP addresses that can be used in a network
• Subnetting - The process of dividing a network into smaller network sections. This can be useful for many different purposes and helps isolate groups of hosts together and deal with them easily.
• Netmask - a 32-bit mask used to divide an IP address into subnets and specify the network's available hosts.
• Connection - In networking, a connection refers to pieces of related information that are transfered through a network.
• Packet - A packet is, generally speaking, the most basic unit that is transfered over a network. When communicating over a network, packets are the envelopes that carry your data (in pieces) from one end point to the other.
• Protocol - A protocol is a set of rules and standards that basically define a language that devices can use to communicate. There are a great number of protocols in use extensively in networking, and they are often implemented in different layers.
• Port - A port is an address on a single machine that can be tied to a specific piece of software. It is not a physical interface or location, but it allows your server to be able to communicate using more than one application.
• Firewall - A firewall is a program that decides whether traffic coming into a server or going out should be allowed. A firewall usually works by creating rules for which type of traffic is acceptable on which ports. Generally, firewalls block ports that are not used by a specific application on a server.
• NAT - NAT stands for network address translation. It is a way to translate requests that are incoming into a routing server to the relevant devices or servers that it knows about in the LAN. This is usually implemented in physical LANs as a way to route requests through one IP address to the necessary backend servers.
• VPN - VPN stands for virtual private network. It is a means of connecting separate LANs through the internet, while maintaining privacy. This is used as a means of connecting remote systems as if they were on a local network, often for security reasons.
• IP address - An Internet Protocol address (IP address) is a logical numeric address that is assigned to every single computer, printer, switch, router or any other device that is part of a TCP/IP-based network.

In mathematics and digital electronics, a binary number is a number expressed in the base-2 numeral system or binary numeral system, which uses only two symbols: typically "0" (zero) and "1" (one). Critical elements of computer networks like addresses, masks, and keys all involve binary or hexadecimal numbers. Understanding how such binary and hexadecimal numbers work is essential in building, troubleshooting, and programming any network

All binary numbers have equivalent decimal representations and vice versa. To convert binary and decimal numbers manually, you must apply the mathematical concept of positional values.You know that an IP address is numbers that represent a device on a network, as a mailing address represents your home's location. But in order to actually assign and use IP addresses, you must understand the format of these "numerical identifiers" and the rules that pertain to them. You may also have heard people referring to the four numerical values in an IP address as "octets". Octet is, in fact, the correct term for describing the four individual numbers that make up an IP address.

Above, you can see that the bits with the values 64, 32, 8, 4 and 2 are all turned on. As mentioned before, calculating the value of a binary number means totaling all the values for the "on" bits. So for the binary value in the table, 01101110, we add together 64+32+8+4+2 to get the number 110. Binary arithmetic is pretty easy once you know what's going on.

The Open Systems Interconnection model (OSI model) is a conceptual model that characterizes and standardizes the communication functions of a telecommunication or computing system without regard to its underlying internal structure and technology. Its goal is the interoperability of diverse communication systems with standard communication protocols. The model partitions a communication system into abstraction layers. The original version of the model defined seven layers.

A layer serves the layer above it and is served by the layer below it. For example, a layer that provides error-free communications across a network provides the path needed by applications above it, while it calls the next lower layer to send and receive packets that constitute the contents of that path. Two instances at the same layer are visualized as connected by a horizontal connection in that layer.

A layer serves the layer above it and is served by the layer below it. For example, a layer that provides error-free communications across a network provides the path needed by applications above it, while it calls the next lower layer to send and receive packets that constitute the contents of that path. Two instances at the same layer are visualized as connected by a horizontal connection in that layer.

Layer 1. Physical Layer - The first layer of the seven layers of Open Systems Interconnection (OSI) network model is called the Physical layer. Physical circuits are created on the physical layer of Open Systems Interconnection (OSI) model. Physical layers describe the electrical or optical signals used for communication. Physical layer of the Open Systems Interconnection (OSI) model is only concerned with the physical characteristics of electrical or optical signaling techniques which includes the voltage of the electrical current used to transport the signal, the media type (Twisted Pair, Coaxial Cable, Optical Fiber etc), impedance characteristics, physical shape of the connector, Synchronization etc.

Layer 2. Datalink Layer - The Data Link layer resides above the Physical layer and below the Network layer. Datalink layer is responsible for providing end-to-end validity of the data being transmitted. The Data Link Layer is logically divided into two sublayers, The Media Access Control (MAC) Sublayer and the Logical Link Control (LLC) Sublayer.

Layer 3. Network Layer - The third layer of the seven layers of Open Systems Interconnection (OSI) network model is the Network layer. The Network layer of the OSI model is responsible for managing logical addressing information in the packets and the delivery of those packets to the correct destination. Routers, which are special computers used to build the network, direct the data packet generated by Network Layer using information stored in a table known as routing table. The routing table is a list of available destinations that are stored in memory on the routers. The network layer is responsible for working with logical addresses. The logical addresses are used to uniquely identify a computer on the network, but at the same time identify the network that system resides on. The logical address is used by network layer protocols to deliver the packets to the correct network. The Logical addressing system used in Network Layer is known as IP address.

Layer 4. Transport Layer - The Transport layer handles transport functions such as reliable or unreliable delivery of the data to the destination. On the sending computer, the transport layer is responsible for breaking the data into smaller packets, so that if any packet is lost during transmission, the missing packets will be sent again. Missing packets are determined by acknowledgments (ACKs) from the remote device, when the remote device receives the packets. At the receiving system, the transport layer will be responsible for opening all of the packets and reconstructing the original message. Another function of the transport layer is TCP segment sequencing. Sequencing is a connection-oriented service that takes TCP segments that are received out of order and place them in the right order.

Layer 5. Session Layer - The session layer is responsible for establishing, managing, and terminating connections between applications at each end of the communication. In the connection establishment phase, the service and the rules (who transmits and when, how much data can be sent at a time etc.) for communication between the two devices are proposed. The participating devices must agree on the rules.

Layer 6. Presentation Layer - When the presentation layer receives data from the application layer, to be sent over the network, it makes sure that the data is in the proper format. If it is not, the presentation layer converts the data to the proper format. On the other side of communication, when the presentation layer receives network data from the session layer, it makes sure that the data is in the proper format and once again converts it if it is not.

Layer 7. Application Layer - Application Layer is the top-most layer of the seven layered Open Systems Interconnection (OSI) network model. Real traffic data will be often generated from the Application Layer. This may be a web request generated from HTTP protocol, a command from telnet protocol, a file download request from FTP protocol etc.

Amazon Web Services (AWS) provides the Networking tools and resources that enable you to securely connect to the cloud and then isolate, control, and distribute your applications across EC2 compute resources and all other relevant services in AWS. Networking Solutions available from AWS Partner Network (APN) partners can help you establish your secure, scalable, cost-effective cloud presence more rapidly. Whether you are planning to migrate to AWS or are looking to expand your established network capabilities on the cloud, there are readily available tools and resources at your disposal to accelerate the realization of your goals.

• VPC A virtual private cloud - a private network space in which you can run your infrastructure. It has an address space (CIDR range) which you choose e.g. 10.0.0.0/16. This determines how many IP addresses you can assign within the VPC. The 10.0.0.0/16 address space can use the addresses from 10.0.0.0 to 10.0.255.255, which is 65,536 IP addresses.
• Availability Zones - is an isolated location inside a region, at least one zone should be able to operate, even if others suffer outages
• Security Groups - specifies ingress (inbound) and egress (outbound) traffic rules, limiting them to certain sources (inbound) and destinations (outbound). They are associated with EC2 instances rather than subnets.

The complete picture of your virtual private network looks something like the picture below, with public and private subnets spread across availability zones, network address translation sitting in the public subnets and route tables to specify how packets are routed. EC2 instances are run in any subnet and have security groups attached to them.

ifconfig is used to configure network interface parameters.

traceroute print the route packets take to network host.

dig (Domain Information Groper) is a flexible tool for interrogating DNS name servers.

• Everything You Need To Know About Networking On AWS -- Graham Lyons
• Networking Solutions -- AWS
• An Introduction to Networking Terminology, Interfaces, and Protocols -- Justin Ellingwood via Digital Ocean
• 10 Useful Linux Networking Commands -- Chandan Kumar via Geek Flare
• Seven Layers of OSI Model and functions of seven layers of OSI model -- OmniSecu.com