- •Using Your Sybex Electronic Book
- •Acknowledgments
- •Introduction
- •Assessment Test
- •Answers to Assessment Test
- •Types of Network Security Threats
- •Types of Security Weaknesses
- •Technology Weaknesses
- •Configuration Weaknesses
- •Policy Weaknesses
- •Types of Network Attacks
- •Eavesdropping
- •Denial-of-Service Attacks
- •Unauthorized Access
- •WareZ
- •Masquerade Attack (IP Spoofing)
- •Session Hijacking or Replaying
- •Rerouting
- •Repudiation
- •Smurfing
- •Password Attacks
- •Man-in-the-Middle Attacks
- •Application-Layer Attacks
- •Trojan Horse Programs, Viruses, and Worms
- •HTML Attacks
- •The Corporate Security Policy
- •Summary
- •Exam Essentials
- •Key Terms
- •Written Lab
- •Review Questions
- •Answers to Written Lab
- •Answers to Review Questions
- •Authentication Methods
- •Windows Authentication
- •Security Server Authentication
- •PAP and CHAP Authentication
- •PPP Callback
- •Configuring the NAS for AAA
- •Securing Access to the Exec Mode
- •Enable AAA Locally on the NAS
- •Authentication Configuration on the NAS
- •Authorization Configuration on the NAS
- •Accounting Configuration on the NAS
- •Verifying the NAS Configuration
- •Troubleshooting AAA on the Cisco NAS
- •Summary
- •Exam Essentials
- •Key Terms
- •Commands Used in This Chapter
- •Written Lab
- •Review Questions
- •Hands-On Labs
- •Lab 2.1: Setting the Line Passwords
- •Lab 2.2: Setting the Enable Passwords
- •Lab 2.3: Encrypting your Passwords
- •Lab 2.4: Creating Usernames and Logging In
- •Lab 2.5: Configuring AAA Authentication on the NAS
- •Answers to Written Lab
- •Answers to Review Questions
- •Introduction to the CiscoSecure ACS
- •Using User Databases for Authentication
- •Populating the User Database Population
- •New ACS Features
- •Installing CiscoSecure ACS 3.0
- •Administering CiscoSecure ACS
- •TACACS+ Overview
- •Configuring TACACS+
- •Using RADIUS
- •CiscoSecure User Database NAS Configuration for RADIUS
- •Verifying TACACS+
- •Summary
- •Exam Essentials
- •Key Terms
- •Commands Used in This Chapter
- •Written Lab
- •Review Questions
- •Answers to Written Lab
- •Answers to Review Questions
- •Solving Eavesdropping and Session Replay Problems
- •Fighting Rerouting Attacks
- •Fighting Denial-of-Service Attacks
- •Turning Off and Configuring Network Services
- •Blocking SNMP Packets
- •Disabling Echo
- •Turning Off BOOTP and Auto-Config
- •Disabling the HTTP Interface
- •Disabling IP Source Routing
- •Disabling Proxy ARP
- •Disabling Redirect Messages
- •Disabling the Generation of ICMP Unreachable Messages
- •Disabling Multicast Route Caching
- •Disabling the Maintenance Operation Protocol (MOP)
- •Turning Off the X.25 PAD Service
- •Enabling the Nagle TCP Congestion Algorithm
- •Logging Every Event
- •Disabling Cisco Discovery Protocol
- •Disabling the Default Forwarded UDP Protocols
- •Summary
- •Exam Essentials
- •Key Terms
- •Commands Used in This Chapter
- •Written Lab
- •Review Questions
- •Hands-On Lab
- •Lab 4.1: Controlling TCP/IP Services
- •Answers to Written Lab
- •Answers to Review Questions
- •Understanding the Cisco IOS Firewall
- •Authentication Proxy and IDS
- •Context-Based Access Control
- •CBAC Compared to ACLs
- •CBAC-Supported Protocols
- •Introduction to CBAC Configuration
- •Using Audit Trails and Alerts
- •Configuring Global Timeouts and Thresholds
- •Configuring PAM
- •Defining Inspection Rules
- •Applying Inspection Rules and ACLs to Router Interfaces
- •Configuring IP ACLs at the Interface
- •Testing and Verifying CBAC
- •Summary
- •Exam Essentials
- •Key Terms
- •Commands Used in This Chapter
- •Written Lab
- •Review Questions
- •Hands-On Labs
- •Lab 5.1: Configure Logging and Audit Trails
- •Lab 5.2: Define and Apply Inspection Rules and ACLs
- •Lab 5.3: Test and Verify CBAC
- •Answers to Written Lab
- •Answers to Review Questions
- •Introduction to the Cisco IOS Firewall Authentication Proxy
- •Configuring the AAA Server
- •Configuring AAA
- •Configuring the Authentication Proxy
- •Testing and Verifying Your Configuration
- •show Commands
- •Clearing the Cache
- •Introduction to the Cisco IOS Firewall IDS
- •Initializing Cisco IOS Firewall IDS
- •Configuring, Disabling, and Excluding Signatures
- •Creating and Applying Audit Rules
- •Setting Default Actions
- •Creating an Audit Rule
- •Applying the Audit Rule
- •Verifying the Configuration
- •Stopping the IOS Firewall IDS
- •Summary
- •Exam Essentials
- •Key Terms
- •Commands Used in This Chapter
- •Written Lab
- •Review Questions
- •Hands-On Labs
- •Lab 6.1: Enabling the IOS Firewall Authentication Proxy
- •Lab 6.2: Enabling the IOS Firewall IDS
- •Answers to Written Lab
- •Answers to Review Questions
- •What is a Virtual Private Network?
- •Introduction to Cisco IOS IPSec
- •IPSec Transforms
- •IPSec Operation
- •The Components of IPSec
- •IPSec Encapsulation
- •Internet Key Exchange (IKE)
- •Summary
- •Exam Essentials
- •Key Terms
- •Written Lab
- •Review Questions
- •Answers to Written Lab
- •Answers to Review Questions
- •Configuring Cisco IOS IPSec for Pre-Shared Keys Site-to-Site
- •Preparing for IKE and IPSec
- •Configuring IKE
- •Configuring IPSec
- •Testing and Verifying IPSec
- •Configuring IPSec Manually
- •Configuring IPSec for RSA-Encrypted Nonces
- •Configuring Cisco IOS IPSec Certificate Authority Support Site-to-Site
- •Configuring CA Support Tasks
- •Preparing for IKE and IPSec
- •Configuring CA Support
- •Configuring IKE Using CA
- •Configuring IPSec for CA
- •Testing and Verifying IPSec for CA
- •Summary
- •Exam Essentials
- •Key Terms
- •Commands Used in This Chapter
- •Written Lab
- •Review Questions
- •Hands-On Labs
- •Lab 8.1: Configure IKE on Lab_A and Lab_B
- •Lab 8.2: Configure IPSec on Lab_A and Lab_B
- •Answers to Written Lab
- •Answers to Review Questions
- •Answers to Hands-On Labs
- •Answer to Lab 8.1
- •Answer to Lab 8.2
- •Introduction to Cisco Easy VPN
- •The Easy VPN Server
- •Introduction to the Cisco VPN 3.5 Client
- •Easy VPN Server Configuration Tasks
- •Pre-Configuring the Cisco VPN 3.5 Client
- •Summary
- •Exam Essentials
- •Key Terms
- •Written Lab
- •Review Questions
- •Hands-On Lab
- •Lab 9.1: Installing the Cisco VPN 3.5 Client Software on Windows
- •Answers to Written Lab
- •Answers to Review Questions
- •Network Separation
- •Three Ways through a PIX Firewall
- •PIX Firewall Configuration Basics
- •Configuring Interfaces
- •Saving Your Configuration
- •Configuring Access through the PIX Firewall
- •Configuring Outbound Access
- •Configuring Inbound Access
- •Configuring Multiple Interfaces and AAA on the PIX Firewall
- •Configuring Multiple Interfaces
- •Implementing AAA on the PIX Firewall
- •Configuring Advanced PIX Firewall Features
- •Failover
- •Outbound Access Control
- •Logging
- •SNMP Support
- •Java Applet Blocking
- •URL Filtering
- •Password Recovery
- •Glossary
136 Chapter 4 Cisco Perimeter Router Problems and Solutions
Review Questions
1.Which routing protocols can use MD5 authentication? (Choose all that apply.)
A.EIGRP
B.BGP
C.OSPF
D.IGRP
E.RIPv1
2.Which IOS feature should be used when hiding multiple hosts behind a single IP address?
A.IPX
B.PAT
C.BGP
D.IPSec
E.DHCP
3.Which IOS feature best prevents rerouting attacks?
A.IPSec
B.TCP Intercept
C.MD5 authentication
D.ACLs
4.Which IOS feature best prevents the lack of legal IP address problem?
A.NAT
B.TCP Intercept
C.MD5 authentication
D.ACLs
5.Which IOS feature best prevents unauthorized access, data manipulation, and malicious destruction problems?
A.NAT
B.TCP Intercept
C.MD5 authentication
D.ACLs
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Review Questions |
137 |
6.You have just configured TCP Intercept. Which type of problem are you trying to solve?
A.DoS attacks
B.Rerouting attacks
C.Lack of legal IP addresses
D.Eavesdropping
7.Which IOS feature best prevents eavesdropping?
A.NAT
B.TCP Intercept
C.MD5 authentication
D.ACLs
E.IPSec
8.You have just configured ACLs at the perimeter router of your network. Which problem are you trying to solve?
A.DoS
B.Rerouting
C.Lack of legal IP addresses
D.Unauthorized access, data manipulation, and malicious destruction problems
E.Eavesdropping
9.Which of the following can use a single IP address to address up to 64,000 internal hosts?
A.NAT
B.PAT
C.IPSec
D.TCP Intercept
10.Which TCP Intercept mode will proxy-answer incoming SYN requests and not notify the server until the originating host is verified?
A.Intercept mode
B.Secure mode
C.Monitor mode
D.None of the above
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138 Chapter 4 Cisco Perimeter Router Problems and Solutions
11.Which command would you configure on the perimeter router if you do not want it to announce to external hosts which subnets are not configured?
A.no source-route
B.no ip unreachables
C.no ip route-cache
D.no service udp-small-servers
12.You want to disable Finger replies on a perimeter router. Which command do you want to use?
A.no finger
B.no finger reply
C.no service finger
D.disable finger
13.Which commands would you use on your router to prevent a chargen attack? (Choose all that apply.)
A.no ip redirects
B.no tcp-small-servers
C.no ip-source route
D.no chargen enable
E.no udp-small-servers
F.no service finger
14.___________ can be used to encrypt data between two networks, which prevents eavesdropping.
A.CBAC
B.Lock and Key
C.IPSec
D.TCP Intercept
15.In a rerouting attack, the ___________ table is modified or prevented from being updated.
A.ARP
B.Address
C.Routing
D.Bridging
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Review Questions |
139 |
16.Which command disables Cisco Discovery Protocol on a perimeter router?
A.no cdp enable
B.no cdp forwards
C.no cdp redirects
D.no cdp run
17.What command is used to enable an HTTP server on a router for AAA?
A.http server
B.http-server
C.ip http server
D.ip http-server
18.Which command disables Cisco Discovery Protocol on a perimeter router interface?
A.no cdp enable
B.no cdp forwards
C.no cdp redirects
D.no cdp run
19.What command will disable proxy ARP on a perimeter router?
A.disable proxy-arp
B.disable ip proxy-arp
C.no proxy-arp
D.no ip proxy-arp
E.no ip proxy arp
20.What command is used to disable the sending of redirect messages?
A.no redirects
B.no ip redirects
C.no interface redirects
D.disable ip redirects
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