# Introduction

## What is a VPN?

Virtual private network (VPN) - is a technology that extends a private network across a public network (Internet) and enables users to send and receive data across shared or public networks as if their computing devices were directly connected to the private network (no matter of the physical location of those devices).

Generally speaking, VPN is a concept and there are various implementations for it. The main difference between those is **a network protocol** (a set of rules on sequence and structure for the requests and responses between a client machine and a server), which defines the qualities (**stability**, **integrity**, **security**, and **speed**) of the connection.

Our solution is based on "[WireGuard](https://www.wireguard.com/)" protocol. It is a **modern**, **fast**, and **reliable** VPN protocol with following benefits:

* supports **modern cryptography** standards
* uses really **fast cryptography** code
* **connects and reconnects faster** than other VPN protocols, even when you are roaming across networks 

## Why do you need it?

### To provide a secure data channel for your customers

All the data is **encrypted** during the VPN session, which **guarantees** no third person can have access to the data your clients' are sending or receiving through the network. The connection process itself is also protected with the **Transport Layer Security** protocol.

This is especially important due to the increasing availability and popularity of **free WiFi networks** in the world. Those are **often used to** compromise the connection and **steal the data**.

### To keep your customers' physical location private

These days, Internet users are **constantly at risk** of collecting and reselling any information about themselves or their activities. This fact creates **an increased demand** to keep such information confidential. When a user connects to the VPN server, his location looks **the same as the location of this VPN server** to anybody over the Internet. 

## How do you get one?

There are severals ways you can embed **a reliable VPN in your application**:

### Use our SDK

Cover the **whole market with our SDK** for the two most popular mobile operating systems. SDK is **a ready-to-go set of functions** you can use in your applications' code. You just need to **download the SDK**, add it to your project and use it according to the **up-to-date documentation**:

{% content-ref url="apple-ios-sdk" %}
[apple-ios-sdk](https://fendai.gitbook.io/fendvpn-docs/apple-ios-sdk)
{% endcontent-ref %}

{% content-ref url="broken-reference" %}
[Broken link](https://fendai.gitbook.io/fendvpn-docs/broken-reference)
{% endcontent-ref %}

{% hint style="info" %}
Windows and macOS SDK are on the way
{% endhint %}

### Use our API

In case you do not want to include our SDK in your application, we provide a **powerful REST API**. It allows you to do everything from the user authentication to VPN connection establishment, so you can **build** **your own SDK** on-top.

{% content-ref url="client-api" %}
[client-api](https://fendai.gitbook.io/fendvpn-docs/client-api)
{% endcontent-ref %}

### Ask us to build an application for you

Sometimes it may be a better choice to rely on the experienced team. We can provide **a full-cycle production** including: 

* Requirements gathering 
* UI design 
* Development 
* Quality assurance 
* Documentation 
* Maintenance

## Why are your customers safe with us?

Because of the several things we do and do not:

* we provide **best possible encryption** during the VPN session
* we keep our servers up to date for the **best protection** of your clients
* we hire **best engineers** on the market to provide our service
* we **do not gather** the exact location of your clients
* we **do not keep** personal identifiable information about your clients
* we **do not log** your clients' network requests

## How can you be sure our system is reliable?

We are so confident in our system that we are ready to provide you with a demo version of the backend that you can run and test on your own:

{% content-ref url="backend-demo-kit" %}
[backend-demo-kit](https://fendai.gitbook.io/fendvpn-docs/backend-demo-kit)
{% endcontent-ref %}