This glossary will help you get a better understanding about the different features, technologies and other aspects related to smart DNS and services like it including VPN services. These various expressions and acronyms are not hard to understand, but they do require a minimal amount of knowledge with IT to process. Nevertheless, there is nothing difficult about them. For example, the terms server and host (the machine that sends data) are interchangeable and will appear throughout this article. Client refers to the recipient of information, the machine that receives data. We are however keeping in mind that since this website is mostly related to VPN and smart DNS services, technical details that are not necessarily important in the context of them will not be included.
A smart DNS, or rather a smart DNS proxy server, is a type of server that lets you access all and any of the online content it provides access to. Today, the distribution of smart DNS servers is mostly done by companies that sell such services. Connecting to a smart DNS server is always done by changing the DNS address of your internet connection either manually, or automatically with the help of a third party program.
VPN (Virtual Private Network)
The internet is a type of public network. By contrast, a VPN is a type of private network, reserved for those only who have access to it. Most VPN services are designed in a way that hides the user from plain sight – the user’s actions are much harder to detect by any party than simply going online with a subscription internet service. There are two major (and several minor) components for making a network private instead of public. The first is encryption, which is encoding your data traffic with a layer of additional data, thus making whatever you do very hard to detect.
The second major component is the IP address of your internet connection. Most VPN services change your IP address, so that you can access online content you cannot otherwise. Therefore, there are two main functions for a VPN: this, the unblocking of restricted material, and protecting this act, with encryption. This is almost always necessary, as most countries’ leaders are keen on restricting the knowledge you can get access to on the internet.
A proxy is a type of server that is a “bellboy” between other servers. A proxy is useful if there is no direct connection between two other servers, for example if internet restrictions prohibit it. In these cases, a proxy has access to both, thus creating an opportunity for the two other servers to exchange data through itself.
DDNS (Dynamic DNS)
As its name suggests, a Dynamic DNS refers to a method that changes DNS addresses automatically, or semi-automatically. Various smart DNS companies use this method in order to make their DNS network less detectable (as otherwise, a smart DNS connection is not encrypted, it is exposed).
Primary DNS & Secondary DNS
A primary DNS address is the address that determines what kind of content you are able to view on the Internet. Primary here stands for the address being the first reference point for the in- and outgoing queries of your machine. A secondary DNS is essentially a backup DNS address. If for any reason your primary address does not function, your machine will automatically refer to this secondary address.
A DNS Cache is a storage segment, designed to contain entries that translates the internet domain names you use (for example: site.com) unto IP addresses. A DNS Cache helps a lot in keeping your internet connections up to date. For example, IP addresses can change. The DNS Cache keeps any change associated with the connection info of domains up to date.
The problem of DNS leaks comes into question when you use a service like a VPN or a smart DNS. Your Internet Service Provider (ISP) can still potentially identify what you do if either your IP or DNS addresses are exposed or unchanged. Since a VPN does not change your DNS address, it can still be tracked by whoever decides to do so, giving them knowledge of what you are doing online.
Transparent HTTP Proxy
A transparent HTTP proxy is a type of proxy in which functionally, it serves as a substitute for a router. This solution processes the data that it intercepts, but does not change it in any way.
HTTPS is a web proxy and is a safer version of HTTP that is mainly used in web browsers as well. The reason for this is that is it encrypted.HTTP traffic is compatible with port 443 of your TCP protocol.
Transparent DNS Proxy
Transparent DNS proxy is a type of proxy most often used by ISPs. From a given client, it will block any DNS requests except the one(s) authorized by the ISP. This means that the Internet Service Provider forces you to use their internet connection in a way that they can completely oversee. If you are using a smart DNS service for example, but it does not seem to work after you have changed your DNS address, being proxied in this way might be one possible explanation.
Socket Secure (SOCKS) is a private proxy variant. Its main advantage is that you can authenticate the proxy, reserving its usage for select individuals only. Although it was not its intended usage, it still allows bypassing online restrictions, since a proxy server is put between the client and the server.
IPv4 is today’s most commonly used type of Internet Protocol (IP). Its main function is facilitating Internet access via providing addresses, “license plates” for different connections (for example: 18.104.22.168). In an address, each number represents one byte worth of information, meaning that IPv4 can supply a total of 232 addresses.
IPv6 is a more advanced version of IPv4, both in terms of capacity and safety. Unlike its predecessor, an address can acquire hexadecimal (a set of 16 characters instead of just 10 numbers) values, resulting in 2128 different possible identifiers for internet connections.
OpenVPN is an application of which’s main agenda is providing secure connections online. It is open-source, meaning that people can use the source code of the application freely to improve it. As a safety tool, OpenVPN works with encryptions, which in the case of VPN and smart DNS companies may vary. Today, there is one major software based on OpenVPN: SoftEther.
Point-to-Point Tunneling Protocol (PPTP) is a method of implementation, most commonly used in VPN networks. It is the least safe of the security options in online safety today, particularly in authentication. Some countries (like China) have the capability to block such connections coming in and out. We do not recommend using PPTP.
Layer 2 Tunneling Protocol (L2TP) is another type of protocol used in Virtual Private Networks. It is more commonly used with mobile devices. It is worth noting that in itself, it is not an encrypted protocol. Because of this, it is often used in unison with IPSec (see below).
Secure Socket Tunneling Protocol (SSTP) is a type of tunneling most commonly used in VPN services. Its main agenda is providing additional security to L2TP traffic in the form of encryption, and others.
IPSec is a protocol used to encrypt your data traffic. It is mostly implemented together with other protocols that are less safe or do not offer encryption at all. It is important to note that IPSec protects data from a gateway to a host, and from client to host, for example.
TCP (Transmission Control Protocol) is the most commonly used protocol to assist in data transportation on the Internet today. Together with the Internet Protocol (IP) they complement each other and are often mentioned as TCP/IP. The Transmission Control Protocol is almost always used for file transferring because of its error-checking capabilities and controlled procedure.
UDP (User Datagram Protocol) is a less reliable counterpart of TCP. It requires fewer resources to run, but it is connectionless, meaning that the data your machine sends is not guaranteed to arrive at a certain destination. Because of this, UDP is often used in openly distributing data, or broadcasting.
Re-routing is a process that is used when data fails to reach a destination through its original route. If this failure happens, the data will change its path onto a backup route, hence it “re-routes”, finds another way to reach its destination. To supply an example, imagine the data as a mole, traveling underground in a straight line, next to other straight tunnels. However, the mole hits a rock. Instead of turning back to start over in another one (which is also a re-routing), the mole bores a hole to the next closest tunnel and continues onward. In computing, this similarly involves detecting the failure, establishing a backup line and then switching onto it.