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Commands used in Dockefile - Part4

  Docker is an opensource tool used for virtualization and deliver software in the form of packages called Containers. It is one of the most important tools used in networking domain.  Dockerfile  is a template for building the image which contains commands needed to package the software. In this post, I am going to explain the commands ADD & COPY used in  Dockerfile .   ADD Command:   ADD command is used to copy files, directories or files from remote URLS to destination path in the image. The source paths can contain wildcards.   If the destination has relative path, it is relative to the Working directory of the image. Note that source path is always relative to the Docker build context.   ADD command will not support authentication. So, if there are any protected files to be added in  Dockerfile  building, use other tools like curl or  wget   Dockerfile  copying Single & Multiple files, directory using ADD inst...

Important Terminologies in Computer Networking

In this article, the basic important terminologies in the networking are explained: 

Connection: 
A connection is nothing but successful completion of arrangements so that two or more parties can communicate with each other at a long distance. It is deconstructed at the end of the data transfer.

Packet: 
A packet is the basic unit of the data that is transferred over a network. In communication using network, these packets carry data from one endpoint to another endpoint. The packet contains header which contains information about the source, destination, hops etc. and main data which is called as payload. 

Networking Interface: 
Networking Interface is nothing but a piece of software that can be used to configure and control the networking hardware of the system. 

Local Area Network (LAN): 
Local Area Network is a network that is not accessible to the greater internet. An example of a LAN network may be a home or office network. 

Wide Area Network (WAN): 
Wide Area Network is a network that is greater than LAN and is generally used to describe large and dispersed networks. If a network interface is connected to WAN, it is reachable through the internet.

Protocol: 
A protocol is a set of rules and standards based on which the network devices can communicate with each other.  Examples of protocols include TCP, UDP, SMTP, HTTP etc. 

Port: 
Port is nothing but an address on the single machine linked with a piece of software. It is not a physical location or interface. It allows the server to be able to communicate with more than a single application.

Firewall: 
Firewall is a program that controls the allow or disallow of incoming and outgoing traffic.  It works on the basis of rules which defines the type of traffic acceptable on which ports. It blocks the ports that are not used by the server or any application.

Network Address Translation (NAT): 
Network Address Translation is a process in which network device generally firewall assigns a public IP address to a group of computers inside a private network. The main goal of NAT is to limit the number public IP addresses used for an organization for economy and security purposes.

Virtual Private Network (VPN): 
Virtual Private Network is the process of connecting separate Local Area Networks through the internet while maintaining security. This is generally used for connecting remote systems as if they were on a LAN. 

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