Home > Articles > Home & Office Computing > Microsoft Windows Desktop

This chapter is from the book

This chapter is from the book

VPN Support

A Virtual Private Network (VPN) enables you to extend the functionality of your private network to a remote network by using the Internet as the backbone. VPNs can be used in several different scenarios. ISA Server uses Windows 2000's Routing and Remote Access service to manage VPNs and offers wizards to configure VPNs in two of the most popular scenarios:

  • A branch office connecting to another branch office

  • Employees connecting to the corporate network remotely

A VPN enables users to exchange information between two computers as if they were connected via a point-to-point link. Even though these computers can be located in remote sites, the information exchanged is encrypted and therefore secure. For example, let's assume that your Human Resources (HR) director, Shannon, wants to be able to work from home. With a VPN, you could allow her to access your corporate network via her Internet connection at home by creating a virtual "tunnel," as shown in Figure 3.12. First Shannon will use her modem to connect to her ISP. Then she will make a second connection to create a VPN tunnel to the corporate network. Once connected to the network, Shannon will be able to perform most of the tasks that she normally does while she is on the corporate network at work. She will be able to access the HR database, print to the network printers, access files in her home folder, and surf the Internet. Because Shannon handles confidential employee information, it is imperative that the data traveling between her home computer and the corporate network is secure. Creating a virtual tunnel encrypts data traveling inside the tunnel and offers the level of security that she needs.

Figure 3.12 A VPN tunnel from home to corporate network through an ISP.

In addition to the users, entire networks, such as branch offices, can access your corporate network via a VPN. Again, data is encrypted between both ends of the VPN tunnel; therefore all communication is secure. For example, if you have offices in Seattle and San Francisco and you want to use the Internet as a secure tunnel between the two offices, you can set up an ISA Server in both cities and create a virtual tunnel between them, as shown in Figure 3.13.

Figure 3.13 VPN tunnel between two offices across the Internet.

NOTE

For additional reading, check out my article "VPN Deployment Using Windows 2000" on the Microsoft TechNet CD, or online at http://www.microsoft.com/technet/treeview/default.asp?url=/technet/columns/profwin/pw0201.asp. The article covers configuring a VPN server, levels of encryption supported by VPNs, and the PPTP and L2TP packet structure.

PPTP, L2TP, and IPSec

In order to create VPNs that are secure, ISA Server supports the use of several protocols that will help you develop your VPN infrastructure. ISA server uses Point-to-Point Tunneling Protocol (PPTP) and Layer 2 Tunneling Protocol (L2TP) to create VPNs across TCP/IP-based networks. The use of IP Security protocol (IPSec) is also supported to help ensure secure data transfer across the Internet, or between computers within a local area network. Let's look at these protocols in more depth.

PPTP

PPTP is an extension to the Point-to-Point Protocol (PPP) and supports multiple protocols that will communicate over the Internet. A PPTP tunnel encapsulates IP, IPX/SPX and NetBEUI protocols inside PPP datagrams. This means that you can use a NetBEUI application on a server across the Internet, even though NetBEUI is not a routable protocol and therefore cannot be used to communicate directly on the Internet. PPTP doesn't require any dial-up connections. For example, if you already have a T1 or DSL connection to the Internet, you simply create a PPTP tunnel. In a typical scenario, a home user can dial into the ISP's server with a modem, which will connect the user to the Internet, and then create a second connection using PPTP and establish a VPN.

As mentioned earlier, PPTP can encrypt data passing through the VPN tunnel. It uses Microsoft Point-to-Point Encryption (MPPE) to encrypt data either with the default 40-bit encryption, or the stronger 128-bit encryption. Installing Windows 2000 Service Pack 2 on Windows 2000 computers will automatically upgrade the encryption level to 128-bit.

TIP

If you want MPPE to encrypt data, use MS-CHAP, MS-CHAP v2, or EAP/TLS authentication. MS-CHAP v2 and EAP/TLS support mutual authentication; therefore, if these protocols are the only protocols configured, make sure that both the server and the clients support them. The connection will be disconnected if, for example, the server doesn't identify itself to the client.

L2TP

L2TP is a combination of Layer 2 Forwarding (L2F) and PPTP. It provides similar functionality as PPTP to establish VPN connections. Although configuring PPTP on the server is much simpler, L2TP offers a higher level of security. With PPTP, you can use MPPE to encrypt data. With L2TP, you use IPSec to encrypt data. When using L2TP, you need to ensure that both the VPN client and the VPN server support L2TP and IPSec. In addition, keep in mind that only Windows 2000 and Windows XP support L2TP and IPSec; Windows NT and Windows 9x don't.

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.

Overview


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information


To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.

Surveys

Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.

Newsletters

If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information


Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.

Security


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.

Children


This site is not directed to children under the age of 13.

Marketing


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information


If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.

Choice/Opt-out


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information


Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents


California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure


Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.

Links


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact


Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice


We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020