CNPA study plan

Diagram the OSI and TCP/IP models side by side, labeling the PDU, addressing, and representative protocols at each layer.

Explain the encapsulation and de-encapsulation process for a web request from browser to server, naming each header added or removed.

Classify ten common network devices and protocols (switch, router, firewall, ARP, DNS, DHCP, HTTP, TLS, ICMP, VLAN) by the OSI layer(s) they operate at and justify each placement.

Calculate the effect of adding a Layer 2 switch versus a router on broadcast domains and collision domains in a small topology.

Compare cut-through, store-and-forward, and fragment-free switching and state one scenario where each is preferred.

Trace a frame through a three-switch topology, showing how the MAC address table is built, aged, and used for forwarding, flooding, and filtering.

Configure VLANs, 802.1Q trunking, and access ports on a simulated or real switch, then verify with show commands.

Explain the purpose and operation of STP/RSTP, including root bridge election, port roles, and one convergence improvement in RSTP.

Differentiate collision domains and broadcast domains and calculate their counts for a given switched topology.

Convert between binary, decimal, and hexadecimal for IPv4 addresses and subnet masks without a calculator.

Subnet a given Class C and Class B network into a specified number of subnets and list network, broadcast, and usable host ranges.

Apply VLSM to allocate addresses for a topology with point-to-point links and LANs of different sizes, documenting the allocation plan.

Identify private, loopback, link-local, and multicast IPv4 ranges and explain when each is used.

Summarize IPv6 address types (global unicast, link-local, unique local, multicast) and the purpose of SLAAC.

Explain the difference between static and dynamic routing and list two use cases for each.

Describe how a router builds its routing table and selects the best path using longest-prefix match and administrative distance.

Compare distance-vector and link-state protocols, naming at least one example of each and their loop-prevention mechanisms.

Configure and verify static routes and a single-area OSPF adjacency in a lab, then interpret the output of show ip route and show ip ospf neighbor.

Trace the DHCP DORA process and explain how a DHCP relay allows clients on different subnets to obtain addresses.

Describe the DNS resolution process from stub resolver to recursive resolver to authoritative server, and distinguish A, AAAA, CNAME, and MX records.

Explain how HTTP/HTTPS, SMTP, and SSH use TCP versus UDP, and identify the default port for each.

Capture a DNS query and an HTTP request in a lab or with a local tool, and annotate the key fields in each.

Compare 2.4 GHz and 5 GHz bands on range, throughput, and channel overlap, and recommend a band for a given scenario.

Explain the purpose of SSIDs, BSSIDs, and association, and describe how a client roams between access points.

Differentiate WPA2-Personal, WPA2-Enterprise, and WPA3, including the role of 802.1X/EAP in enterprise authentication.

Identify common wireless interference sources and propose two configuration changes to reduce co-channel interference.

Explain the CIA triad and map three common attacks (phishing, on-path attack, DoS) to the triad component each primarily threatens.

Describe how a stateful firewall differs from a stateless ACL and give one rule that demonstrates the difference.

Explain the role of NAT and PAT in reducing exposure of internal addresses, and configure a basic NAT rule in a lab.

Outline how TLS provides confidentiality and integrity for HTTPS, naming the roles of certificates and the handshake.

Apply a structured troubleshooting method (identify, hypothesize, test, resolve, document) to three simulated faults: no link, no DHCP address, and unreachable remote subnet.

Use ping, traceroute, ipconfig/ifconfig, and show interface/route commands to isolate faults at Layers 1–3.

Interpret common interface counters (CRC errors, late collisions, duplex mismatch) and state the likely cause of each.

Create a final one-page quick-reference of commands and concepts across all eight domains.