Discuss Both Advantages And Disadvantages Of Remote Authentication Protocols.
Access Control, Authentication, and Public Key Infrastructure
Lesson 12
Access Control Solutions for Remote Workers
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Access Control, Authentication, and PKI
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1
Learning Objective
Implement a secure remote access solution.
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Access Control, Authentication, and PKI
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2
Key Concepts
Remote access solutions
Remote access protocols with their respective applications
Virtual private networks (VPNs), Secure Sockets Layer (SSL), and Citrix
Secure Web authentication examples
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3
Remote Access Methods
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RADIUS
RAS
TACACS+
VPN
Identification, Authentication, and Authorization (IAA)
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USB Tokens:
Password required(second authentication factor) to gain access to the computer system
Hard to duplicate and tamper resistant
Ability to store digital certificates that can be used in a public key infrastructure (PKI) environment
Key Questions to Discuss:
Does second authentication factor assure complete security?
Even though USB devices are hard to duplicate and tamper resistant, what factors still allow sensitive information stored in USBs vulnerable?
Can you come up with more weaknesses or strengths of USBs???
Smart Cards—Advantages
Contains a microprocessor–enables storage and processing of data and use of more robust authentication schemes:
Valid recognition of smart card (first authentication factor)
Requirement of password (second authentication factor)
Smart Cards—Disadvantage Requires installation of a hardware reader and associated software drivers on the consumer’s home computer
Why is it a disadvantage? Let’s discuss!!!!
Password Generating Tokens
Unique pass-code, also known as a one-time password (OTP)—ensures that the same OTP is not used consecutively
User name and regular password (first authentication factor)
OTP generated by the token (second authentication factor)
What makes password generating tokens so secure ???
Password-generating tokens are secure because of the time-sensitive, synchronized nature of the authentication. The randomness, unpredictability, and uniqueness of the OTPs substantially increase the difficulty of a cyber thief capturing and using OTPs gained from keyboard logging.
Biometric Techniques and Identifiers
Fingerprint Recognition
Face Recognition
Voice Recognition
Keystroke Recognition
Handwriting Recognition
Finger and Hand Geometry
Retinal Scan
Iris Scan
Key Questions to Discuss for Biometrics
How can biometrics help financial institutions in replacing the use of Automated Teller Machine (ATM) cards?
Currently, some financial institutions, domestic and foreign, that use fingerprint recognition and other biometric technologies to authenticate ATM users, are eliminating the need for an ATM card and the expense of replacing lost or stolen cards.
Once enrolled, customers interact with the live-scan process of the biometrics technology. The live scan is used to identify and authenticate the customer.
Web Browsers
Today, Web browsers such as Internet Explorer, Mozilla Firefox, and Apple Safari (to name a few), are installed on almost all computers. Because Web browsers are used so frequently, it is vital to configure them securely.
Often, the Web browser that comes with an operating system is not set up in a secure default configuration.
Not securing your Web browser can lead quickly to a variety of computer problems caused by anything from spyware being installed without your knowledge to intruders taking control of your computer.
Vulnerabilities
Ideally, computer users should evaluate the risks from the software they use. Many computers are sold with software already loaded. Unfortunately, it is not practical for most people to perform this level of analysis.
There is an increasing threat from software attacks that take advantage of vulnerable Web browsers.
We have observed a trend whereby new software vulnerabilities are exploited and directed at Web browsers through use of compromised or malicious Web sites.
This problem is made worse by a number of factors, including the following:
Many users have a tendency to click on links without considering the risks of their actions.
Web page addresses can be disguised or take you to an unexpected site.
Many Web browsers are configured to provide increased functionality at the cost of decreased security.
http://www.cert.org/tech_tips/securing_browser
Key Questions to Discuss
Are Web browsers secure?
What are the vulnerabilities of Web browsers?
Why do we need to secure the Web browsers?
How can Web browsers be made secure?
Reducing Risks in Web Browsers Force authentication(strong authentication preferred)
Configure browser for safe operation
Use remote access server (RAS) to validate access
Use secure protocols
Use host and network firewalls
Use antivirus (update it frequently)
Guard against malware
8/20/2018
5
Identification
The process of uniquely distinguishing an individual
Authentication
The process of verifying that users are who they say they are
Authorization
Determining which actions are allowed or not allowed by a user or system
Access Protocols to Minimize Risk
Authentication, Authorization, and Accounting (AAA)
Remote Authentication Dial In User Service (RADIUS)
Remote Access Server (RAS)
Terminal Access Controller Access Control System Plus (TACACS+), XTACACS, and TACACS+
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Authentication, Authorization, and Accounting (AAA)
Network services that provide security through:
A framework of access controls and policies
Enforcement of policies
Information needed for billing purposes
Framework that multiple protocols are based on
Example: RADIUS protocol uses the AAA framework to provide the three AAA components, but supports authentication and authorization separately from accounting
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Remote Authentication Dial In User Service (RADIUS)
A client/server protocol that provides authentication and authorization for remote users
Also provides accounting capabilities
A network protocol providing communication between a network access server (NAS) and an authentication server
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RADIUS Infrastructure
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Remote Access Server (RAS)
Provides authentication for remote access in an Internet and dial-up scenario
Process:
User connects to the RAS
Credentials are compared against database
If credentials match, authentication has occurred, and user is granted access to the network
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TACACS+
A Cisco-proprietary protocol developed to provide access control for routers, network access servers, and other network devices via one or more centralized servers
Utilizes TCP, ensuring message delivery
Is an extension of TACACS but differs by:
Separating authentication, authorization, and accounting architecture
Encrypts the communication
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RADIUS vs. TACACS+
Attributes RADIUS TACACS+
Transport Protocol User Datagram Protocol (UDP) Transmission Control Protocol/Internet Protocol (TCP/IP)
Encryption Encrypts only password Encrypts the entire body of the packet
Authentication, authorization, and accounting (AAA) Not considered a pure AAA architecture Pure AAA
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Remote Authentication Protocols
Point-to-Point Protocol (PPP)
Challenge Handshake Authentication Protocol (CHAP)
Extensible Authentication Protocol (EAP)
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EAP over RADIUS
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Virtual Private Networks (VPNs)
A secure connection over an unsecure network—the Internet
Security over VPN is provided through encryption
Tunneling protocols
Point-to-Point Tunneling Protocol (PPTP)
Layer 2 Tunneling Protocol (L2TP)
Internet Protocol Security (IPSec)
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Web Authentication
Ensuring users are who they say they are through a Web application
User ID and password is the basic form of authentication
Other forms of authentication:
One-time password authentication
Digital certificates
Knowledge-based authentication (KBA)
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Best Practices for Remote Access Controls to Support Remote Workers
Determine the security risk associated with remote access
Select a remote access option that addresses security needs
Determine the appropriate level of authentication based on the security risk
Ensure the systems that are accessing the network meet the security policies of the organization
Ensure protection of the systems that remote workers access
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Access Control, Authentication, and PKI
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Summary
Remote access methods
Remote access management
RADIUS versus TACACS+
Remote access implementation requirements
Security concerns in remote access
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Access Control, Authentication, and PKI
© 2015 Jones and Bartlett Learning, LLC, an Ascend Learning Company
www.jblearning.com