Cisco Certified Network Associate (CCNA) IP Services Syllabus

IP Services syllabus — full chapter and topic list

Expand any chapter to see its topics and sub-topics. This is the whole examinable outline for IP Services in Cisco Certified Network Associate (CCNA), not a summary of it.

1. 1

   Network Address Translation

   4 topics

   • NAT concepts and terminology
     • Inside/outside local and global
     • Use cases for NAT
   • Static NAT configuration
   • Dynamic NAT and PAT (overload)
     • NAT pools
     • Port address translation
   • Verifying and troubleshooting NAT translations
2. 2

   Time and Logging Services

   3 topics

   • NTP operation in client/server mode
     • Stratum levels
     • Configuring NTP clients and servers
   • Syslog severity levels and configuration
     • Severity 0-7 meanings
     • Logging to console, buffer, and server
   • SNMP function in network operations
     • Managers, agents, and MIBs
     • Traps and informs
     • SNMPv2c vs SNMPv3
3. 3

   Address Assignment Services

   3 topics

   • DHCP role and operation
     • DORA process
     • Configuring a router as DHCP server
     • DHCP relay (ip helper-address)
   • DNS role and resolution process
     • Name-to-IP resolution
     • DNS record types overview
   • Verifying client address services
4. 4

   Quality of Service and File Transfer

   3 topics

   • QoS forwarding concepts
     • Classification and marking
     • Congestion management and queuing
     • Policing and shaping
   • Per-hop behavior and trust boundaries
   • Remote file transfer with TFTP and FTP

IP Services flashcards for Cisco Certified Network Associate (CCNA)

25 of 65 cards from the IP Services deck — real questions with worked answers.

1. What is the primary purpose of Network Address Translation (NAT)?

   To translate private IP addresses into public (globally routable) IP addresses, conserving public address space and allowing internal hosts to access the Internet.

2. In NAT terminology, what is an 'inside local' address?

   The private IP address assigned to a host on the inside network, as seen from inside the network (before translation).

3. In NAT terminology, what is an 'inside global' address?

   The public IP address that represents an inside host to the outside world (the translated address used on the Internet).

4. In NAT terminology, what is an 'outside global' address?

   The real public IP address of an outside (Internet) host, as assigned by its owner.

5. In NAT terminology, what is an 'outside local' address?

   The IP address of an outside host as it appears to the inside network (often the same as the outside global address).

6. Which RFC 1918 private address ranges are commonly translated by NAT?

   10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16.

7. What is static NAT?

   A fixed one-to-one mapping between a single inside local address and a single inside global address, configured manually.

8. What is a typical use case for static NAT?

   Allowing inbound access to an internal server (e.g., web/mail server) by giving it a permanent public address mapping.

9. What Cisco command creates a static NAT mapping?

   ip nat inside source static <inside-local> <inside-global> (in global config mode).

10. How do you designate router interfaces for NAT?

    Use 'ip nat inside' on the internal-facing interface and 'ip nat outside' on the external-facing interface, in interface config mode.

11. What is dynamic NAT?

    NAT that maps inside local addresses to public addresses drawn from a pool, on a first-come first-served basis (one-to-one but not fixed).

12. What happens in dynamic NAT when the address pool is exhausted?

    Additional hosts requesting translation are denied (packets dropped) until an existing translation times out and frees an address.

13. What is PAT (NAT overload)?

    Port Address Translation maps many inside local addresses to a single inside global address by using unique source port numbers to distinguish sessions (many-to-one).

14. How does PAT differentiate multiple internal hosts sharing one public IP?

    By assigning a unique TCP/UDP source port number to each translation, tracked in the NAT table.

15. What keyword enables PAT (overload) on a Cisco dynamic NAT configuration?

    The 'overload' keyword, e.g., ip nat inside source list 1 pool POOLNAME overload.

16. How can PAT use the outside interface's IP address directly instead of a pool?

    ip nat inside source list <ACL> interface <outside-interface> overload.

17. What command defines the address pool used by dynamic NAT/PAT?

    ip nat pool <name> <start-ip> <end-ip> netmask <mask> (or prefix-length).

18. What identifies which inside hosts are eligible for dynamic NAT translation?

    A standard access control list (ACL) referenced by the ip nat inside source list command.

19. Which command displays the current active NAT translation table?

    show ip nat translations.

20. Which command shows NAT statistics such as hits, misses, and configured interfaces?

    show ip nat statistics.

21. Which command clears dynamic NAT translation entries?

    clear ip nat translation * (or specify a particular entry).

22. What debug command shows NAT activity in real time for troubleshooting?

    debug ip nat.

23. A NAT translation works but the host has no Internet access; what common cause should you check?

    Verify correct ip nat inside/outside interface assignments, the ACL matches the hosts, the pool/route is valid, and the default route exists.

24. What is the purpose of NTP (Network Time Protocol)?

    To synchronize the clocks of network devices to a common, accurate time source for accurate logging, certificates, and timestamps.

25. What transport protocol and port does NTP use?

    UDP port 123.

See more IP Services flashcards →

Planning IP Services for Cisco Certified Network Associate (CCNA)

IP Services (Cisco Certified Network Associate (CCNA)) FAQ