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The tremendous growth in demand for

service provider-based,dial access to VPNs

is being driven by the many factors

described below.

The Internet as a Viable VPN

There is ever-increasing demand for dial

access to corporate networks,the Internet,

and other online services.Confidence

in the Internet as a viable infrastructure

for conducting business is increasing.

Meanwhile,advanced technologies make

the Internet a viable VPN infrastructure,like

the public Frame Relay and X.25 packet-

switched networks.

Growth in Mobile Computing

There is an emerging paradigm in personal

computer use featuring mobile and work-

at-home telecommuters, and an increase

in small office/home office (SOHO)

access to corporate data centers and

intranets.Much of this is being fueled by

the increased availability of inexpensive

Integrated Services Digital Network (ISDN),

which offers better performance and

reliability than analog dial services,partic-

u l a rly for Inte rnet access and te l e co m m u t i n g.

ISDN is pervasive throughout Europe.

Corporate Focus on Outsourcing

Remote Access Service

Corporate IS departments are seeking to off-

load the significant costs of purchasing and

supporting remote access infrastructures.

Small service providers,offering specialized

information services,are also becoming

interested in outsourcing their dial access

infrastructure to larger service providers.

They look to outsourcing as a way to

contain their own costs and to increase

their efficiency in receiving data from the

carrier network.

Differentiation for Service Providers

Service providers increase revenues and

attract new customers by allowing local

users to access their dial infrastructure and

tunnel through to their corporate networks.

This provides secure point-to-point commu-

nications for corporate users.With tunneling,

data is encapsulated inside IP packets and

routed from the tunnel origination point,

such as a sales representative’s laptop,

through the service provider network to

the tunnel endpoint,such as the sales repre-

sentative’s enterprise network. Additionally,

VPNs are ideal for supporting extranets,

which use the public Internet and Internet

tools such as web browsers to provide

value-added services to end users. An

extranet can be used by a company to give

its preferred customers access to internal

resources such as online ordering or inven-

tory tracking systems that may reside on

the company’s intranet.More and more

companies are implementing extranets as

one way to improve customer satisfaction.

Other example applications include distance

learning and online gaming in which autho-

rized users have access to specific resources.

Congestion in the PSTN

Traditional voice carriers,including many

of the Regional Bell Operating Companies

(RBOCs),report that the circuit switches that

co m p rise the P S T N a re be c oming ove rl o a d e d.

This congestion is due to the long hold

times of computer users accessing corpo-

rate networks,the Internet,and other online

services.Dial VPNs can be used by phone

companies to alleviate congestion at the

end point.

Carriers are playing a key role in providing

dial access to the Internet,whether or not

they provide IP routing or Internet services.

There is tremendous interest among the

telcos in offering both remote access and

whole network outsourcing services to

corporate customers,as well as direct

Internet access using a common remote

access infrastructure.

Applications for the Market

Service providers have evolved a variety

of models for offering VPN solutions

that provide secure,point-to-point data

communications to their users.In fact,

different providers define VPNs in different

ways and the diversity of their offerings

reflect this.For the purposes of this paper,

however,two primary types of VPN services

are most relevant.

The first type of VPN service is one in

which a company outsources its remote

access resources,including modem banks

and analog or digital circuits.The company

might also outsource the personnel

resources required to support a remote

access user community.The second is a

service in which an ISP“wholesales”its

remote access out to a larger provider.The

motivating factors are primarily cost and

efficiency.With many ISPs now offering low

cost or even free Internet access,profit

margins for “plain old”access have eroded

significantly.Instead, many ISPs focus on

content-related services such as gaming,

Internet fax,multicasting, and others.

Additionally,the same T1 facilities that

previously delivered 24 analog modem-

connected subscribers can support many

more subscribers since the data is now

delivered via a statistically multiplexed

network such as Frame Relay.

The Need For Dial VPNs

4 White Paper Understanding and Implementing Dial VPN Services

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