VPN extends a private network over a public network, enabling secure data transfer
A tunnel is established between the client and VPN Server this tunnel encrypts all the data
We are assigned a private IP Address on the VPN Servers network
Types of VPN Configuration
Site-to-site VPN
Establishes secure tunnels over the public internet for interconnecting remote sites
Alternative to having dedicated lease line between sites
Client-to-site VPN
Connects individual devices directly to an organizations office
Allows remote access to company network
Clientless VPN
Secures remote access through browser-based VPN tunnels
No software or hardware configuration is required
e.g. HTTPS
VPN Tunnel Types
Supported by site-to-site VPN and client-to-site VPN
Full Tunnel
Maximizes security by encrypting all traffic
When connected to VPN wont be able to access local network devices
Half Tunnel
Divides traffic and network requests and routes them to the appropriate network
Traffic to office will be sent over VPN while other traffic will be over public internet
Not as secure as Full Tunnels but provides better performance
VPN Security Protocols
Transport Layer Security (TLS)
Protocol that provides cryptographic security for secure connections and is used for secure web browsing and data transfer
TCP is used by TLS to establish secure connections between client and server
This can slow down the connection
Datagram Transport Layer Security (DTLS)
UDP-based version of TLS protocol
Same security as TLS while providing faster operations
Useful for video-streaming over VPN
Internet Protocol Security (IPSec)
A protocol suite for secure communication that provides authentication and encryption of data packets on IP networks
Used in site-to-site VPN and client-to-site VPN
IPsec Protocol Suite
VPN Concentrator
Allows to manage multiple VPN connections in a single location
Used by organization to allows remote users to connect to the work network from anywhere in the world
VPN Headend is a special type of concentrator used to terminates IPSec VPN tunnels