VPN by Amin Pathan

VIRTUAL PRIVATE VIRTUAL PRIVATE NETWORKS (VPN)NETWORKS (VPN)

ByByMr. Amin PathanMr. Amin Pathan

(M.Tech-CSE Pursuing, BE-IT)(M.Tech-CSE Pursuing, BE-IT)

Traditional Connectivity Traditional Connectivity

[From Gartner Consulting][From Gartner Consulting]

What is VPN?What is VPN?

Virtual Private Network is a type of private Virtual Private Network is a type of private network that uses public telecommunication, network that uses public telecommunication, such as the Internet, instead of leased lines to such as the Internet, instead of leased lines to communicate.communicate.

Became popular as more employees worked in Became popular as more employees worked in remote locations.remote locations.

Terminologies to understand how VPNs work.Terminologies to understand how VPNs work.

Remote Access Virtual Private Remote Access Virtual Private NetworkNetwork

(From Gartner Consulting)

Brief Overview of How it WorksBrief Overview of How it Works

Two connections – one is made to the Internet Two connections – one is made to the Internet and the second is made to the VPN.and the second is made to the VPN.

Datagrams – contains data, destination and Datagrams – contains data, destination and source information.source information.

Firewalls – VPNs allow authorized users to pass Firewalls – VPNs allow authorized users to pass through the firewalls.through the firewalls.

Protocols – protocols create the VPN tunnels.Protocols – protocols create the VPN tunnels.

Four Critical FunctionsFour Critical Functions

AuthenticationAuthentication – validates that the data was sent – validates that the data was sent from the sender.from the sender.

Access controlAccess control – limiting unauthorized users from – limiting unauthorized users from accessing the network.accessing the network.

ConfidentialityConfidentiality – preventing the data to be read or – preventing the data to be read or copied as the data is being transported.copied as the data is being transported.

Data IntegrityData Integrity – ensuring that the data has not been – ensuring that the data has not been altered altered

EncryptionEncryption

Encryption -- is a method of “scrambling” data Encryption -- is a method of “scrambling” data before transmitting it onto the Internet.before transmitting it onto the Internet.

Public Key Encryption TechniquePublic Key Encryption Technique

Digital signature – for authenticationDigital signature – for authentication

TunnelingTunneling

A virtual point-to-point connectionA virtual point-to-point connection

made through a public network. It transportsmade through a public network. It transports

encapsulated datagrams.encapsulated datagrams.

Encrypted Inner Datagram

Datagram Header Outer Datagram Data Area

Original Datagram

Data Encapsulation [From Comer]

Two types of end points: Remote Access Site-to-Site

Four Protocols used in VPNFour Protocols used in VPN

PPTP -- Point-to-Point Tunneling ProtocolPPTP -- Point-to-Point Tunneling Protocol

L2TP -- Layer 2 Tunneling ProtocolL2TP -- Layer 2 Tunneling Protocol

IPsec -- Internet Protocol SecurityIPsec -- Internet Protocol Security

SOCKS – is not used as much as the ones SOCKS – is not used as much as the ones above above

VPN Encapsulation of PacketsVPN Encapsulation of Packets

Types of ImplementationsTypes of Implementations

What does “implementation” mean in VPNs?What does “implementation” mean in VPNs?

3 types3 typesIntranet – Within an organizationIntranet – Within an organizationExtranet – Outside an organizationExtranet – Outside an organizationRemote Access – Employee to BusinessRemote Access – Employee to Business

Virtual Private Networks (VPN)Basic Architecture