Firewall is one of best security mechanism that monitor and control the network traffic incoming and outgoing, based on predefined security rules. The firewall is always established between trusted internal and some other outside network (can be internet), assuming that outside network unsecured and untrusted. There are mainly two kinds of firewalls, host-based firewalls and network firewalls. Some of firewall provide additional services like DHCP (Dynamic Host Configuration Protocol) or VPN (Virtual Private Network) services for the internal network. There are Three generations of firewalls named First, Second and Third. First generation firewalls were based on packet filtering. Looking at the network address (IP) and the port of the packet, it determined whether packet is to block or allowed. If a particular packet or series of packets did not match for packet filtering rules, those were simply dropped. In 1988 first packet filter firewall was developed from Digital Equipment Firewalls. If packets do not match the rules, the filter will reject or drop the packet. These filtering works on the first three layers (physical layer, data link layer and network layer) of the OSI (Open Systems Interconnection) model.

Secure Shell (SSH) is a cryptographic protocol with the focus for secure data communication over a network. It's most common application is for remote login by users onto other systems; usually servers. The protocol was designed to be the successor and replacement to Telnet and other similar unsecured remote shell protocols as they all sent information in plain text which made them privy to attacks. As this information was user login credentials, the demand for the encryption of this data was something deeply sought after to ensure security. While the protocol does achieve this function, recent incidents involving the files leaked by Edward Snowden has revealed that the National Security Agency (NSA) is actually capable of sometimes decrypting the protocol.

The File Transfer Protocol (FTP) is a protocol used in the Internet Protocol (IP) Suite used for the transferring of files across a network between a server and a client. The protocol was built from the ground up with the client-server model in mind and utilizes different connections for data and control between the two. Users can authenticate themselves with a clear-text sign-in protocol which is usually in the form of a username and password or they can connect to the server anonymously if it is configured to allow it. Transmissions of a user's login credentials can be secured by Transport Layer Security / Secure Sockets Layer (TLS/SSL); which can also encrypt the content of transmissions. Should this not be the case, the information is transmitted unencrypted which leaves it susceptible to a sniffing attack. In some scenarios, SSH File Transfer Protocol (SFTP) might be used but it should be noted that the protocol is technologically different than TLS/SSL.

In the last two decades or so, a number of new ways through which we can access the internet have been introduced. Traditionally, the internet could be accessed via telephone wires, satellites, cables, and mobile devices. Often, tethering and hotspot are confused with each other.

InterPlanetary File System (IPFS) is a protocol which seeks to replace the Hypertext Transfer Protocol (HTTP) with the goal of having a truly decentralized Internet by changing how data is communicated across the World Wide Web (WWW). This is accomplished by a decentralized network where all devices on the network have hypermedia content stored and content-addressed for sharing. This process makes it similar to the World Wide Web (WWW), however, it is very different as it creates another network which works alongside a file system. The protocol was realized in 2014 by using the Bitcoin blockchain protocol and network as its framework which allowed it to store immutable data, handle duplicated files, and obtain addressing information across the network. This led to achieving faster speeds, more reliable performance, and better security than HTTP and HTTPS although it is not popular nor commonplace.

The Hypertext Transfer Protocol (HTTP) is a protocol at the application layer of the Internet Protocol (IP) Suite. The protocol is used for distributed, collaborative, and hypermedia information systems which put it at the core of data communication across the World Wide Web (WWW). This means that when a user goes to a (distributed or collaborative information systems) website or loads any form of interactive media (hypermedia information systems), it is this protocol which transfers the information back and forth. Hypertext is structured text which has the feature of logical links (hyperlinks) between endpoints. This means that HTTP is literally the protocol to handle the transfer of hypertext.

It's now very easy doing online transactions on the go than ever before. Thanks to a mobility of devices and smartphones. However, if you are a person who likes connecting to free public Wi-Fi hotspots you need to be careful or avoid it altogether.

An Internet Service Provider (ISP) is an organization which provides internet services to users. These organizations can be commercial, non-profit, private, or even community-owned. One of the key services they provide is the ability for their users to access the Internet. Laptops, computers, mobile devices, and any smart device that is capable of connecting to the Internet will require an ISP to connect to the Internet. To accomplish this, the ISP will provide the user with their own IP Address, which may be static or dynamic, to use as identification while surfing the internet. The user would then browse a website from their web browser by typing in its website name; let's say, iplocation.net. This website name (domain name) would be translated into its own IP Address which uniquely identifies the website via DNS. This IP Address is then sent to the user's local router which is then forwarded to the user's ISP and then from there; to iplocation's ISP via ISP Switching centers like Metropolitan Area Exchange (MAE). Other services an ISP may provide include Internet transit, web hosting, Usenet service, and co-location services. Internet transit is a service provided to allow a smaller ISP to connect to the Internet and have their network traffic "transit" over a network. Web Hosting is provided to users who require a means to keep their website active and available but lack the equipment to do it themselves. Usenet was one of the first means of communication on the Internet that was designed back in the 70s and is no longer used. Finally, co-location is the service of providing server space and equipment for rental to hosting customers.

The Domain Name System (DNS) is a decentralized naming schema of resolving domain (host) names into numerical IP Addresses. The IP Addresses are assigned to various computing devices and services on the Internet but because remembering a series of numbers is difficult for people, it's easier to remember them by their corresponding domain names and have the DNS translate it into the relevant IP address.

The term intranet is comprised of two words: "Intra" means internal and the "net" represents the network. The Intranet, therefore, can be defined as the internal network. It is a private network with access limited to the authorized users only. The Intranet can be as simple as a private website or it can be as big as private organizational infrastructure, accessed by only the authorized users. The intranet may not necessarily be connected to the Internet but they usually do. In typical intranet architecture, there are specific computers in a defined parameter where each computer in the intranet plays a specific role to provide common tools and features to every computer connected to the intranet. There are vendors that provide the intranet portal software like Share Point, Igloo, and Huddle.