News & Tools
- AT&T Takes Steps to Mitigate Botnet Found Inside Its Network – AT&T is battling a modular malware called EwDoor on 5,700 VoIP servers, but it could have a larger wildcard certificate problem.
- ‘Double-Extortion’ Ransomware Damage Skyrockets 935%
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,
- 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
- 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:
- 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 18.104.22.168 22.214.171.124 netmask 255.255.255.0
- Instead of the netmask command, you can use the _____________ statement.
- An inside local address is before or after translation?
- An inside global address is before or after translation?
- Outside Local
- Outside 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
- Source addressing
- One-way NAT
Chapter 12: IP Services
- 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?
- 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?
- What’s command to specify the source to synchronize time with?
- 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
- 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
- Read Chapter 13: Security, Authentication
- Do the Written Labs
- Answer the Review Questions
- Do not submit your answers for this chapter. The answers are in Appendix.