CST3607 Class Notes 2021-12-02

News & Tools

Exam 3

Chapter 10: Security: Access Control Lists (ACL)

  • You will need to decode an ACL to determine:
    • which IP addresses or networks are being denied or allowed,
    • which protocols are being denied or allowed,
    • whether the rule applies to inbound our outbound traffic,
    • etc.
  • Standard Access Lists
    • Standard Access Lists can check for what in the IP packet?
    • Is a Standard ACL applied closest to the destination or closest to the source?
    • What are the access-list numbers for a Standard ACL?
  • Extended Access Lists
    • Extended Access Lists can check for what in the IP packet?
    • Is an Extended ACL applied closest to the destination or closest to the source?
    • What are the access-list numbers for an Extended ACL?
  • What is an Implicit Deny?
  • An Inbound access list is applied to inbound packets on an interface, before being routed.
    • Why is an inbound access list applied before the packet is routed?
  • An Outbound access list is applied to outbound packets on an interface.
  • Why must an access list must be applied to an interface to be effective?
  • Configuring ACLs
    • access-list
    • access-group
    • access-class
  • Security Appliances
  • Determine the Subnet Block Sizes
    • Use the block size to determine the subnet ranges

Chapter 11: Network Address Translation (NAT)

Network Address Translation (NAT) allows many inside IP addresses to be represented by some smaller number of outside/public IP addresses.

Types of NAT, and how they work:

  • Static
  • Dynamic
  • Port Address Translation (PAT) a.k.a. NAT Overload
  • What type of address translation can use only one address to allow thousands of hosts to be translated globally?
  • In the following output, what type of NAT is being used? 
    ip nat pool todd-nat 170.168.10.10 170.168.10.20 netmask 255.255.255.0
  • Instead of the netmask command, you can use the _____________ statement.

NAT terms

  • An inside local address is before or after translation?
  • An inside global address is before or after translation?
  • Outside Local
  • Outside Global

CCNA CCNP Training – No confusion with IP NAT Inside Outside Local Global

  • Using ACLs with NAT
    • What are the Cisco IOS commands to define the NAT ACL, and then to apply the ACL to an interface?
  • Configure and verify NAT for given network requirements
    • NAT Diagnostic Commands and output
    • Which command will show you the translation table?
    • Which command can you use to show the NAT translations as they occur on your router?
    • Which command will clear all your NAT entries from the translation table?
    • Which command can be used for troubleshooting and displays a summary of the NAT configuration, as well as counts of active translation types, and hits to an existing mapping?
    • Which commands must be used on your router interfaces before NAT will translate addresses?
    • Once you create a pool for the inside locals to use to get out to the global Internet, what is the command to allow them access to the pool?
  • Operation of IP Data Networks
    • Predict the data flow between two hosts across a network
  • Identify the basic operation of NAT
    • Purpose
    • Pool
    • Static
    • one-to-one
    • Overloading
    • Source addressing
    • One-way NAT

Chapter 12: IP Services

  • SNMP
    • Which version of SNMP provides the best security?
    • Which layer of the OSI Reference Model does SNMP function?
    • What is the MIB?
    • How does SNMP use the MIB?
  • syslog
    • What message types are sent to the syslog server?
    • What is the default syslog facility level?
    • What is the command to enable syslog with debugging?
  • NTP
    • What’s command to specify the source to synchronize time with?
  • ICMP
  • Cisco Discovery Protocol (CDP)
    • What is the command to determine the IP address of a directly connected neighbor?
  • Link Layer Discovery Protocol (LLDP)
  • Secure Shell (SSH)
    • What commands are required when configuring SSH on your router?

OSI Reference Model

Cisco IOS Diagnostic Commands

  • show ip interface brief
    • What would the “status” and “protocol” columns display if an interface was not enabled?
    • What would the “status” and “protocol” columns display when an interface is “shutdown?”
    • What would the “status” and “protocol” columns display if an Ethernet interface is enabled, and configured, but the other end of the connection was shutdown?
    • What would the “status” and “protocol” columns display if a Serial interface is enabled, and configured, but the other end of the connection was shutdown?
    • What would the “status” and “protocol” columns display if an interface is enabled, and configured, but the interface was not connected to another device?
    • What would the “status” and “protocol” columns display for a Serial DCE interface, where the clock rate was not set or was zero?

Read / Watch / Do

CCNA Certification Study Guide, Volume 2

  • Read Chapter 14 HSRP
  • Do the Written Labs
  • Answer the Review Questions
    • Do not submit your answers for this chapter. The answers are in Appendix.

Better Focus and Efficient Studying When Not Multitasking