By RSVP’s

What is a VPN?

A virtual network overlaid on top of the ubiquitous interconnection of the Internet

and a private network for confidential communications and exclusive usage.

VPNs

In a virtual private network (VPN), "virtual" implies that there is no physical network infrastructure dedicated to the private network.

Instead, a single physical network infrastructure is shared among various logical networks

In VPNs, various networking technologies are applied toward the goal of providing private communications within the public Internet infrastructure

 

Separate Private Networks.

Private Networks

Why VPNs?

Separate private networking solutions are expensive and cannot be updated quickly to adapt to changes in business requirements.

The Internet is inexpensive but does not by itself ensure privacy.

Virtual Private Networking: the collection of technologies applied to a public network—the Internet—to provide solutions for private networking needs.

The Internet

Ubiquitous Coverage - wider coverage compared with the private data network infrastructures offered by telecommunication providers

Cost Reduction - based on the system's economy of scale

Security – using cryptographic technology

E-Commerce - VPNs provide both interconnectivity and security.

VPN Motivation

The VPN MarketPlace

VPN Products: Hardware and Software that make VPNs possible – A VPN gateway is a stand-alone device that

enables authorized access to the protected network resources. The resources are not located on the same physical device with the VPN gateway

– A VPN client, on the other hand, is installed on the same network device it is supposed to protect. Usually, the client is a software package installed on the host computer.

The VPN MarketPlace

VPN SERVICES:

– Contracted VPN service – Service level agreements (SLAs)

VPN Barriers

Lack of interoperability of IPSec* implementations.

????????Lack of widely used quality of service (QoS) standards, as well as the sparse deployment of QoS-capable infrastructures

Security services in support of VPNs must be constructed from additional hardware and software components as Internet infrastructure is still largely focused on providing connectivity and does not yet offer services beyond connectivity.

*IPSec: Internet Security standards established by IAB

VPN Technologies

Tunneling – using encapsulation Authentication Access Control Data Security

VPN SolutionsVPN solution consists of multiple, appropriately configured VPN devices that are placed in the appropriate locations within the network.VPN Gateway Interface

The VPN client is software used for remote access for a single computer or user.VPN Network and Service Management.

VPN Vendors

Layer 2 Tunneling Protocol (L2TP): utilizing Cisco Systems” Layer-2 Forwarding and Microsoft’s Point-o-Point Tunneling Protocol (PPTP)– Supports IP, IPX, AppleTalk, frame relay, ATM,

S.25 and Sonet

IBM Nways Multiprotocol Routing Services (MRS), Nways Multiprotocol Access Services(MAS) and Access Integration Services(AIS)– Supports IP, APPN,TN3270

And there are many more………

Types of VPNs

Site to Site VPNs– Using ISDN, Frame Relay or ATM– Designed to replace a WAN

Remote Access VPNs– Using the Internet– Provide remote access to mobile or branch

employees

Site-to-Site VPN

VPNs Based on ISDN, Frame Relay or ATM

Site-to-Site VPN vs WAN

Remote Access VPNVPNs Based on IP Tunnels/Internet VPNs

What are the costs?

Using the Cisco website calculator a comparison of three scenarios was made.

Not for small enterprises!!

* www.cisco.com/warp/public/779/largeent/learn/technologies/vpn/site2site.html

Monthly Cost Savings for Site-to-Site VPN

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134055

678255

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0 2000 4000 6000

Number of users

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VPN Directions

Integration of VPN and firewall functions into a single device.

Incorporating routing and quality of service features into the VPN device will make it even more versatile and more attractive to businesses.

Adding intelligence to the network – Currently the routers and switches merely forward the packets without knowing what is inside them or how to process them accordingly. ??

Questions?????

Questions

What is L2TP? PPTP? IPSec?

What types of VPNs are there?

Name two advantages of VPNs?

Name two disadvantages of VPNs?

At which layer of the OSI model do VPNs interact?

And Answers

What is – L2TP? Layer2 Tunneling Protocol from

Cisco and Microsoft.– PPTP? MS Point-to-Point Tunneling

Protocol – IPSec? IP Security, a set of standards for

the Internet security; also implementations of VPN using the set of standards for Internet security

What types of VPNs are there?– Two were described, remote access VPNs

and Site-to-Site VPNs

More Answers

Name two advantages of VPNs?– Cost savings and good way to handle

remote access are two

Name two disadvantages of VPNs?– Security risk and lack of QofS

At which layer of the OSI model do VPNs interact?– Layer 2 or Layer 3