How hard is the CCNP Enterprise ENCOR exam?
The CCNP Enterprise ENCOR (350-401) is a significantly harder exam than CCNA, covering advanced topics in dual-stack IPv4/IPv6 architecture, virtualization, infrastructure, network assurance, security, and automation. Most candidates need 4-6 months of preparation with hands-on lab practice. The exam costs $400 USD and is 120 minutes long with a passing score of approximately 825 out of 1000.
The CCNP Enterprise 350-401 ENCOR (Implementing and Operating Cisco Enterprise Network Core Technologies) exam is the core exam required for the CCNP Enterprise certification and is also one of two exams required for the CCIE Enterprise Infrastructure written requirement. It validates advanced-level networking skills across enterprise infrastructure, virtualization, security, and automation.
CCNP Enterprise certification significantly increases earning potential, with certified network engineers reporting salaries of $100,000-$145,000 in the United States. The exam is widely recognized by enterprises as the benchmark for senior network engineer competency. The exam costs $400 USD and requires approximately 825 out of 1000 to pass.
Exam Overview
| Detail | Information |
|---|---|
| Exam Code | 350-401 ENCOR |
| Full Name | Implementing and Operating Cisco Enterprise Network Core Technologies |
| Number of Questions | 90-110 |
| Time Limit | 120 minutes |
| Passing Score | ~825/1000 |
| Cost | $400 USD |
| Prerequisites | CCNA recommended but not required |
| Certification | CCNP Enterprise (with one concentration exam) |
| Validity | 3 years |
The exam covers six domains:
- Architecture (15%)
- Virtualization (10%)
- Infrastructure (30%)
- Network assurance (10%)
- Security (20%)
- Automation (15%)
"ENCOR is not an exam you pass with flashcards. You need to understand how protocols actually work, be able to troubleshoot when they do not work, and understand the design trade-offs between different implementations. Candidates who understand the 'why' behind each technology consistently outperform those who just memorize configurations." -- Network Chuck, networking educator
Domain 1: Architecture (15%)
Enterprise Network Design Principles
Hierarchical network design organizes the network into three layers:
- Core layer: High-speed backbone providing fast switching between distribution blocks. No policy enforcement; optimized for speed and redundancy.
- Distribution layer: Aggregates access layer connections, applies routing and QoS policies, provides gateway redundancy (HSRP, VRRP, GLBP).
- Access layer: Connects end devices (workstations, IP phones, APs) to the network. Applies security (port security, 802.1X), PoE, and VLAN assignment.
Spine-leaf architecture is the modern data center topology replacing the traditional three-tier design:
- Every leaf switch connects to every spine switch
- No connections between spines or between leaves
- Any-to-any traffic crosses only two hops (leaf-to-spine-to-leaf)
- Provides predictable latency and easy horizontal scaling
SD-WAN and SD-Access
Cisco SD-WAN (Viptela) separates the WAN control and data planes:
- vManage: Centralized management and policy orchestration
- vSmart: Centralized control plane handling routing policies
- vBond: Orchestration plane for initial device onboarding
- vEdge/Catalyst SD-WAN routers: Data plane devices at branch locations
Cisco SD-Access automates campus network provisioning using intent-based networking:
- Fabric: VXLAN-based overlay transporting traffic across the underlay
- DNA Center (Catalyst Center): Management and orchestration platform
- ISE: Policy and identity engine providing dynamic segmentation
Domain 2: Virtualization (10%)
Network Function Virtualization
NFV (Network Function Virtualization) replaces dedicated hardware appliances with software running on standard servers. Examples: virtual routers, virtual firewalls, virtual load balancers.
VXLAN (Virtual Extensible LAN) encapsulates Layer 2 Ethernet frames in UDP packets, allowing Layer 2 network extension across Layer 3 boundaries. Used extensively in data center and SD-Access fabrics.
Virtual Machines and Containers
The exam tests understanding of hypervisors (Type 1 bare-metal vs. Type 2 hosted) and containers (shared OS kernel, more lightweight than VMs). Network engineers must understand how VMs and containers are connected to networks through virtual switches and how networking changes in virtualized environments.
Domain 3: Infrastructure (30%)
Advanced Routing Protocols
OSPF (Open Shortest Path First):
- Uses Dijkstra's SPF algorithm to calculate lowest-cost paths
- Organizes routers into areas to limit LSA flooding scope
- Router types: Internal router, ABR (Area Border Router), ASBR (Autonomous System Boundary Router)
- LSA types 1-7 and their propagation rules across areas
- OSPF authentication (null, clear-text, MD5, SHA)
EIGRP (Enhanced Interior Gateway Routing Protocol):
- Cisco-proprietary advanced distance vector protocol using DUAL algorithm
- Maintains feasibility condition to prevent routing loops
- Successor (primary path) and feasible successor (backup path) concepts
- K-values for metric calculation (bandwidth, delay, load, reliability, MTU)
BGP (Border Gateway Protocol):
- Path-vector protocol used for inter-AS routing and enterprise multi-homing
- EBGP (between different ASes) and IBGP (within an AS)
- BGP attributes and path selection process (Weight, Local Preference, AS-path, MED, and others)
- BGP route filtering with prefix-lists, route-maps, and community strings
Switching Technologies
| Technology | Purpose |
|---|---|
| STP (802.1D) | Classic spanning tree, 30-50 second convergence |
| RSTP (802.1w) | Rapid spanning tree, sub-second convergence |
| MST (802.1s) | Multiple spanning tree instances for VLAN groups |
| VTP | VLAN propagation between switches (use with caution) |
| EtherChannel (LACP/PAgP) | Link aggregation for bandwidth and redundancy |
| MACsec (802.1AE) | Layer 2 encryption for data in transit |
QoS
Quality of Service prioritizes critical traffic to ensure performance:
- DSCP marking: 6-bit differentiated services code point classifies traffic
- Queuing: Priority Queue (PQ), Weighted Fair Queuing (WFQ), Low Latency Queuing (LLQ)
- Traffic shaping vs. policing: Shaping buffers excess traffic; policing drops or marks excess traffic
- NBAR: Network-Based Application Recognition identifies applications for classification
Domain 4: Network Assurance (10%)
Cisco DNA Center (Catalyst Center) Assurance
Catalyst Center provides network assurance through:
- Client 360 and Device 360: Per-client and per-device health views
- Issue correlation: Automated root cause analysis for network issues
- AI-driven insights: Predictive insights about network health trends
Traditional Monitoring Tools
- SNMP: V1/V2c (community string authentication) and V3 (user-based security model with auth and encryption)
- NetFlow/IPFIX: Flow-based traffic analysis for visibility into application flows
- Syslog: Event logging from network devices, severity levels 0-7
- IP SLA: Synthetic traffic generation for measuring network performance (RTT, jitter, packet loss)
Domain 5: Security (20%)
Network Access Control
802.1X provides port-based network access control:
- Supplicant: The end device requesting access
- Authenticator: The switch or wireless AP enforcing access control
- Authentication server: RADIUS server (Cisco ISE) making the access decision
Cisco ISE (Identity Services Engine) provides:
- 802.1X authentication for wired and wireless
- MAB (MAC Authentication Bypass) for devices that do not support 802.1X
- Profiling to automatically identify device types
- SGT (Security Group Tags) for TrustSec microsegmentation
Infrastructure Security
- Control Plane Policing (CoPP): Rate-limiting traffic destined to the router CPU to prevent DoS attacks
- Management Plane Protection: Restricting which interfaces and protocols can be used for management access
- DHCP snooping, Dynamic ARP Inspection, IP Source Guard: Layer 2 security features preventing DHCP/ARP spoofing
Domain 6: Automation (15%)
Network Programmability
Automation tools tested on ENCOR:
- Ansible: Agentless automation using YAML playbooks and SSH/NETCONF
- Python with Netmiko/NAPALM: Library-based network automation
- Cisco IOS-XE REST API: Programmatic interface to router/switch configuration
- NETCONF/YANG: Standards-based network configuration protocol with structured data models
Data Formats
- JSON: Key-value pairs and arrays, widely used for API data exchange
- XML: Hierarchical markup language used in NETCONF
- YAML: Human-readable data serialization used in Ansible playbooks
"Automation is the domain where many experienced network engineers struggle with ENCOR because it requires a different mindset. You do not need to be a software developer, but you need to understand what REST APIs are, how to interpret a basic Python script that talks to a network device, and how YANG data models structure network configuration." -- Cisco certification community
Frequently Asked Questions
Do I need CCNA before attempting CCNP ENCOR? CCNA is not a formal prerequisite for CCNP, but the knowledge from CCNA is assumed in ENCOR exam questions. Candidates without CCNA-level understanding of routing, switching, and networking fundamentals will struggle significantly with the advanced topics. Most training programs recommend earning CCNA first.
How many exams are required for CCNP Enterprise? CCNP Enterprise requires two exams: the core exam (350-401 ENCOR) and one concentration exam of your choice (ENARSI for routing/switching specialists, ENWLSD for wireless design, ENSDWI for SD-WAN, etc.). The concentration exam focuses your certification on a specific technology area.
What is the best lab environment for CCNP ENCOR study? Options include Cisco DevNet Sandbox (free, cloud-based labs), Cisco Modeling Labs (CML, subscription-based virtual lab platform), EVE-NG with Cisco images, or GNS3 with Cisco images. Physical hardware (used Cisco 3850 switches and ISR 4000 routers) provides the most realistic experience but is expensive. Most successful candidates use CML or EVE-NG for topology flexibility.
References
- Cisco. (2025). CCNP Enterprise Certification. https://www.cisco.com/c/en/us/training-events/training-certifications/certifications/professional/ccnp-enterprise.html
- Odom, W. (2023). CCNP and CCIE Enterprise Core ENCOR 350-401 Official Cert Guide. Cisco Press.
- Cisco. (2025). SD-Access Design Guide. https://www.cisco.com/c/en/us/solutions/enterprise-networks/software-defined-access/
- Cisco. (2025). Catalyst Center Documentation. https://developer.cisco.com/docs/dna-center/
- Doyle, J., & Carroll, J. (2022). Routing TCP/IP, Volume 1 (3rd ed.). Cisco Press.
- Cisco DevNet. (2025). Network Programmability Fundamentals. https://developer.cisco.com/