JNCIA-Design study plan
JNCIA-Design · Give each week a clear focus.
8 weeks · About 7 hours per week
Network Design Fundamentals & Campus and Enterprise LAN Design
Define the three-tier and collapsed-core campus models and state two trade-offs of each in writing
Sketch a /24-to-/26 subnetting plan for a 200-host floor and verify every broadcast address by hand
Explain how STP, LACP, and VRRP/HSRP interact in a redundant access-distribution pair
List the design inputs (user count, growth, PoE, uplink oversubscription) you would collect before sizing an access switch
Your checkpoint
A one-page campus reference sheet with the two hierarchy models, a verified subnet table, and a redundancy call-flow diagram
Network Design Fundamentals & Campus and Enterprise LAN Design
Compare OSPF area design choices for a multi-building campus and justify one in a short memo
Size distribution-to-core uplinks using a stated oversubscription target and show the arithmetic
Design a wireless coverage and capacity plan for an open office and a warehouse, noting different AP density drivers
Identify where QoS classification and marking should first occur in an enterprise LAN
Your checkpoint
A campus LAN design document (2-3 pages) covering topology, addressing, uplink sizing, and wireless AP counts with calculations
WAN and Service Provider Connectivity Design & Campus and Enterprise LAN Design
Match three WAN options (MPLS L3VPN, internet with IPsec overlays, dedicated Ethernet) to three stated business requirements
Diagram a hub-and-spoke versus a partial-mesh overlay and identify where traffic tromboning occurs
Explain how BGP route selection order changes the exit path in a dual-homed branch
Describe how MTU and fragmentation behave across an overlay tunnel and what to set on the underlay
Your checkpoint
A WAN option comparison matrix with scoring against cost, latency, availability, and change lead time for three scenarios
WAN and Service Provider Connectivity Design
Draft an IP addressing and summarization scheme that keeps branch routes aggregatable at the provider edge
Explain the difference between provider-assigned and provider-independent address space and the operational consequence
Design a resilient single-branch WAN edge with two providers and state the failover detection mechanism
Describe how CoS/QoS markings must be mapped across an MPLS handoff
Your checkpoint
A branch WAN design with an address plan, two-provider failover logic, and a route summarization table
Data Center Design
Compare spine-leaf and traditional three-tier in a data center and state which workloads favor each
Size an oversubscription ratio for a leaf-spine fabric given a stated east-west traffic profile
Explain VXLAN encapsulation and why an IP underlay is used instead of relying on STP
Describe how server NIC teaming and MLAG/MC-LAG differ in failure behavior
Your checkpoint
A leaf-spine reference design with port counts, oversubscription math, and a failure-domain table
Data Center Design & Network Security Design
Place firewall, load balancer, and DCI boundaries in a data center diagram and justify each insertion point
Compare active-active and active-standby firewall deployment for stateful failover
Identify where east-west security controls differ from north-south and give one enforcement example of each
Describe storage network design considerations (lossless Ethernet or Fibre Channel) at a summary level
Your checkpoint
An annotated data center topology diagram showing security insertion points and traffic flows for three application tiers
Network Security Design
Segment a campus into zones (user, guest, management, DMZ) and define the policy between each pair
Explain zero-trust segmentation versus perimeter-only defense using a concrete example
Design remote access with MFA and describe where the enforcement point sits
List the logging and monitoring sources a security design must feed and what each detects
Your checkpoint
A zone-based security policy matrix with allow/deny rules and a logging source inventory
Network Design Fundamentals & Campus and Enterprise LAN Design & WAN and Service Provider Connectivity Design & Data Center Design & Network Security Design
Re-derive the key sizing formulas (subnetting, oversubscription, AP count) from memory without notes
Review every prior deliverable and correct at least three errors or gaps you find
Answer a timed set of mixed-domain practice questions and categorize each miss by domain
Write a one-page summary of the design trade-offs you would defend in an interview
Your checkpoint
A consolidated design portfolio of all seven prior deliverables plus a scored practice-test log with remediation notes
Milestones
Week 2: Can produce a correct subnet table and justify an uplink oversubscription number unaided in under 15 minutes
Week 4: Can explain BGP exit-path selection and two-provider failover to a non-engineer without notes
Week 6: Can draw a leaf-spine fabric with correct oversubscription math and name three security insertion points
Week 7: Zone policy matrix is complete with no implicit allow rules left undefined
Week 8: Practice-test score is at or above 80% overall with no single domain below 70%