---
description: vpn
---

# 12

### 2 kinds of connections over public network

1. List line

* ISP gives a dedicated link&#x20;
* Very expensive link

1. VPN

* Creates tunnels that allow users to connect over a public network

### VPN Architecture

Remote Access VPN/ Client-to-site VPN

* External users connecting to an internal network through one VPN gateway/server.
* Only one VPN device
* Normally, a piece of software is installed in the user's device



Site-to-Site VPN

* Two VPN appliances
* Connects two separate networks
* No requirement to download any software to access resources in the other network.



### VPN Encryption Protocols

TLS/SSL VPN&#x20;

* Used in client-to-site VPN

IPSec VPN

* Contains several protocols

#### Key IPSec Protocols

Authentication Header (AH) Protocol

* provides authentication, does not support encryption
* mildly obsolete

Encapsulation Security Payload (ESP) Protocol

* provides encryption and authentication\


Internet Key Exchange (IKE) Protocol

* Negotiation of VPN connection tunnel (called security association)
*   Has two phases - Phase 1 and Phase 2

    * Phase 1 - establish a secure channel for communication
    * Phase 2 - Data packets will go through



Configuration Steps

{% hint style="warning" %}
Both IP address of firewall in IKE Protocol should be in the same subnet
{% endhint %}

Checklist

1. Configure L3 Interface
2. Configure Tunnel Interface
3. Configure a new Static Route
4. Setup Crypto Profile&#x20;
5. Setup IKE Gateway
6. Setup IPSec Tunnel
7. Security Policy
8. Test Connection

