Home > Articles

This chapter is from the book

This chapter is from the book

3.2: Understanding Media Security

The essence of a network is that a series of computers are connected in some fashion to one another and transmitting information across some type of media. Although you might have secured your computers and other devices to the strongest extent possible, attackers might still be able to access information as it flows across the wires or from removable media such as CDs, tapes, and disks and use this information for their benefit or for pursuing more potent attacks on your network.

Exercise 3.2.1: Understanding Media Security Concepts

Networking cable types whose security concerns you need to be familiar with include coax (thinnet or 10Base-2 and thicknet or 10Base-5), twisted pair (UTP and STP), and fiber optic. In this exercise, you research the security concerns of these networking media.

  1. From a Web browser, connect to the Internet and navigate to http://www.enterasys.com/support/techtips/tk0399-9.html. This document provides a background of the specifications of the various networking media, which should all be familiar to anyone who has taken the Network+ exam.

  2. Continue to http://c0vertl.tripod.com/text/ethernet.htm and note some problems that exist with the various types of networking cable. Which troubleshooting device do the authors claim can detect tapping of a network cable?

  3. Continue to http://www.puredata.com/supports/faqs/fiber/faqs.html and find out why eavesdropping of fiber-based networks is virtually impossible.

  4. Note the table comparing characteristics of network media at http://website.lineone.net/~paulcon/70-58-2.html. Which type of media is most subject to eavesdropping?

  5. You might want to conduct a search on Google or Yahoo! for additional articles that relate to security concerns of Ethernet media, but be forewarned that not much relevant material is present.

In addition to these sources, review the material provided in the Exam Cram 2 and the Training Guide for the Security+ exam for additional information on networking media security concerns. (See the "Need to Know More?" section at the end of this chapter.)

CAUTION

Keep in mind other properties of network media when it comes to assessing security of the different media types. For example, cabling located in a location subject to electromagnetic interference should be shielded in some manner. STP or fiber optic cable is more suitable to such a location than UTP cable such as standard 10Base-T or 100Base-T installations.

Exercise 3.2.2: Securing Removable Media

Unauthorized users who can remove disks or tapes from a network can steal information from the network; they can also insert disks containing viruses, Trojan horses, sniffers, or other unauthorized software to facilitate other attacks. In this exercise, you look at some of the concerns of removable media security:

  1. Rick Cook discusses the security of backup tapes at http://searchstorage.techtarget.com/tip/1,289483,sid5_gci756807,00.html. What method does he suggest for improving the security of these tapes?

  2. A good source for information on data security management is http://www.degaussing.net/security-issues-in-data-facility-management.html. They review degaussing of magnetic media, including tapes and hard disks, and offer a large number of links to additional sources. Study this reference and enumerate all the issues they discuss related to security of data stored on tapes and disks. Also locate as many reasons as possible for performing complete data erasure on tapes and disks that are no longer required.

  3. Threats to data stored on removable media can come from within the company as well as outside. Note some of the precautions you should observe when planning backup strategies in http://www.nss.co.uk/WhitePapers/data_storage_mment/data_storage_mment.htm. Follow the two "Security" links in the article's table of contents. What is a potential loophole associated with an unattended backup taking place at a user's desktop? What is a potential security breach associated with members of the Backup Operators group also being able to restore data?

  4. Thanks to readily available hardware and software solutions, recordable CDs can present a security problem because it is easy to copy data to a CD and remove it from the premises. Data Link Associates sells a CD/optical media eraser, which they claim can erase all types of CDs. For information on this product, go to http://www.datalinksales.com/degaussers/1200.htm. A hand-cranked device described at http://www.datalinksales.com/degaussers/shredder434355.htm completely destroys CDs and DVDs.

  5. David White discusses systems security at http://www.dbmsmag.com/9711d13.html. His article includes smart card and PCMCIA card security concerns. What is one way in which an unauthorized user can obtain information from a smart card? He also discusses topics of interest related to several other Security+ objectives.

  6. Stephen Wilson discusses smart card and hardware key security at http://www.sans.org/rr/papers/20/763.pdf. We discuss certificate and hardware key security in Chapter 4. What are some of the security features that Wilson mentions? What is the biggest limitation regarding the use of smart cards, and what solution does he advocate for this limitation?

Exercise 3.2.3: Using the Encrypting File System to Encrypt Data in Windows 2000 Server

Starting with Windows 2000, Microsoft made available an easily implemented system of encrypting data on a hard disk with the Encrypting File System (EFS). This method of encryption is especially useful for portable computers that are subject to loss or theft and prevents data from being copied after removing the disk to another computer or by an intruder who does not know the username or password under which the data was encrypted. In this exercise, you encrypt a test file and then attempt to access it as an unauthorized user. Perform this exercise on a computer running Windows 2000 Server. You can also do this exercise on a computer running Windows XP Professional or Windows Server 2003. In any case, the hard disk must be formatted with the NTFS file system:

  1. Log on to the computer running Windows 2000 Server as an administrator.

  2. Open My Computer and navigate to the C: drive.

  3. Create a new folder named Encrypt.

  4. Right-click this folder and choose Properties.

  5. On the General tab of the Encrypt Properties dialog box, click Advanced.

  6. In the Advanced Attributes dialog box that opens, select the Encrypt Contents to Secure Data check box (see Figure 3.8), and then click OK.

  7. Figure 3.8Figure 3.8 Encrypt a folder in Windows 2000 Server.

  8. Click Apply to apply the change.

  9. NOTE

    If you are using Windows XP Professional or Windows Server 2003, you must select the Security tab of the Encrypt Properties dialog box, select the Users entry, select the Full Control permission under the Allow column, and then click OK. Granting this permission is necessary so that you can distinguish the effect of data encryption from that of the application of NTFS permissions, as we discussed in Chapter 1.

  10. Open the Encrypt folder and create a text document by selecting File, New, Text Document and then typing Text1.txt as the filename.

  11. Open this document and type something in the body of the document that identifies the document. Save the document and close Notepad.

  12. Log off and log on as the User1 user you created in Chapter 1.

  13. Navigate to and attempt to open the text document in the C:\Encrypt folder. What happens? You receive an "Access is denied" message because the document was encrypted by the administrator. Any user can create an encrypted document according to permissions specified on the folder in which the document is created.

  14. To prove this point, repeat Steps 8 and 9 to create another document as the User1 user. Then log off and log back on as the administrator and try to open this document. You receive the same message because this document was encrypted by the User1 user. EFS provides this second level of security that is valuable in situations where the computer might be vulnerable to theft or other unauthorized access.

What Did I Just Learn?

Now that you have looked at media concerns, let's take a moment to review all the critical items you've experienced in this lab:

  • You need to keep your network cabling media secure from intrusions such as eavesdropping by means of wiretapping, which can occur on coaxial and twisted-pair networking configurations.

  • Fiber optic cable is more difficult to compromise than coaxial or twisted-pair networking media. However, it is more expensive and difficult to work with. Its usage is mainly in places where physical security is difficult to achieve or where the need for large bandwidth or freedom from electromagnetic interference is required.

  • Removable media such as tapes, CDs, disks, flash cards, and smart cards can present security problems because of the ease of removal from work premises. The same is true with regard to hard disks, although these take more time to remove except in hot-swap configurations.

  • EFS in Windows 2000/XP/2003 provides an additional layer of data security that is especially valuable in situations where theft or loss of portable computers is possible.

Pearson IT Certification Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from Pearson IT Certification 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 Pearson IT Certification 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 Adobe Press. 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.pearsonitcertification.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