(a) . Access to the back-end database will be an important part of the network design. Research and discuss the different possibilities for virtual private network (VPN) access to the back-end database. Include in your discussion the different types of VPNs, their key characteristic, and how they would be set up and used for database access. 

Outline your ideas in a 3–5-paragraph posting. 

Be sure to document your references using APA format. 

(b) 

The command office has asked for a presentation on security mechanisms including access control models, authentication, authorization and encryption. Describe differences between them and identify situations where appropriate. Discuss how encryption relates to storage, network traffic, secure Web access, and the e-mailing of documents. One topic of concern is symmetrical versus public key.

The presentation should include the following information: 

• Comparison of security mechanisms
• An explanation of public key cryptography
• Historical background of the development of encryption
• Typical uses of public key cryptography
• Symmetrical versus public key
• Encryption and how it relates to storage, network traffic, secure Web access and e-mail 

Prepare an 8–15-slide presentation to address these points. Include speaker notes in the presentation. Plan the presentation and speaker notes so that someone else could actually give the presentation.  

Be sure to document your references using APA format.