NET-NEXUS // Cybernetic Network Simulator & Visual Academy

Interactive Encapsulation Engine (TCP/IP vs OSI Model)

See how raw text payload gets wrapped into headers layer by layer before turning into electrical/optical bits!

Payload Data (Application Layer Text)

Target Protocol

Protocol Stack Layer Inspection

7-5

APPLICATION / PRESENTATION / SESSION

Generates raw user payload data (HTTP, SSH, DNS).

4

TRANSPORT LAYER (TCP / UDP)

Adds Port Numbers (Src Port: 54321, Dst Port: 80) & Sequence Numbers.

3

NETWORK LAYER (IP Address)

Adds Logical IPs (Src IP: 192.168.1.50, Dst IP: 8.8.8.8) & TTL.

2

DATA LINK LAYER (Ethernet / MAC)

Adds Physical Hardware MAC Addresses (00:1A:2B:3C:4D:5E) & FCS Trailer.

1

PHYSICAL LAYER (Bits & Voltage)

Converts frame into binary bits (0s and 1s) sent over copper cables or optical light.

assembled PDU Frame Structure STAGE: IDLE

Ethernet Frame Header (Layer 2)

IP Header (Layer 3)

TCP Header (Layer 4)

"HELLO_NETWORK_WORLD_2026"

Physical Wire Signal (Bits):

00000000 00000000 00000000

💡 Key Concept: Encapsulation When sending data, every layer wraps the data with its own control header (like nesting envelopes inside a bigger envelope). At the receiving end, the reverse happens (**Decapsulation**).

Switching Lab: VLAN Tagging & MAC Address Table Simulator

Configure switch ports into VLANs, send frames, and watch MAC Learning and 802.1Q tagging isolate broadcast domains!

NEXUS-24P-MANAGED-SWITCH [L2/L3]

VLAN 10 (Sales) VLAN 20 (Eng) TRUNK (802.1Q)

PORT Gi0/1

VLAN 10

PC-A (00:0A)

PORT Gi0/2

VLAN 10

PC-B (00:0B)

PORT Gi0/3

VLAN 20

DEV-1 (00:0C)

PORT Gi0/4

VLAN 20

DEV-2 (00:0D)

PORT Gi0/5

TRUNK

ROUTER L3

PORT Gi0/6

UNUSED

PORT Gi0/7

UNUSED

PORT Gi0/8

UNUSED

CAM / MAC Address Table

LIVE CAM

VLAN	MAC ADDRESS	TYPE	PORT
10	00:0A:CD:11:22:33	DYNAMIC	Gi0/1
10	00:0B:CD:44:55:66	DYNAMIC	Gi0/2

Switch Event Logs

REALTIME

%SWITCH-6-LINKUP: Interface Gi0/1 changed state to UP

%SWITCH-6-LINKUP: Interface Gi0/2 changed state to UP

%CAM-5-LEARN: Learned MAC 000A.CD11.2233 on Gi0/1 (VLAN 10)

Routing Arena: Dijkstra OSPF & BGP Pathfinding Simulator

Select source/destination nodes, choose routing algorithms, or sever links to witness dynamic failover convergence!

Click nodes to change Source/Destination:

ACTIVE ROUTE SEVERED LINK

R1 (HQ)

10.0.1.1

R2 (ISP-A)

Cost: 10

R3 (ISP-B)

Cost: 50

R4 (DEST)

8.8.8.8

Selected Best Path

R1 ➔ R2 ➔ R4

Total Metric Cost / AS Path

OSPF Cost: 20 (100Gbps Link)

Convergence Status

STABLE (LSA Synchronized)

Modern Enterprise Stack (SD-WAN, Starlink, Wi-Fi 7 & Zero Trust)

Experience modern network innovations: Sub-second WAN failover, Multi-Link Operation Wi-Fi 7, and Zero Trust security.

SD-WAN Dynamic Steering

STEERING

Simulate fiber line degradation and watch SD-WAN seamlessly steer VoIP & ERP traffic to Starlink LEO Satellite in <100ms!

WAN1 (Primary Fiber): HEALTHY (12ms)

WAN2 (Starlink Satellite): STANDBY / ACTIVE

Wi-Fi 7 (802.11be) MLO

320 MHz

Wi-Fi 7 allows devices to transmit simultaneously over multiple bands (2.4GHz, 5GHz, and 6GHz) at once for zero latency!

2.4 GHz Band (Range) ACTIVE (40 MHz)

5 GHz Band (Speed) ACTIVE (160 MHz)

6 GHz Band (Ultra-Fast) ACTIVE (320 MHz)

🚀 Aggregate Speed: Up to 46 Gbps Throughput

Zero Trust Architecture

ZTNA

"Never Trust, Always Verify." Every user and device request is authenticated, authorized, and encrypted before granting access.

Identity Verification (MFA)

Device Posture & Health Check

Micro-segmented Per-App Tunnel

NETWORK_CLI_CONSOLE_v4.0

INTERACTIVE

Welcome to NET-NEXUS Cyber Terminal.

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Network Knowledge Quest

SCORE: 0 PTS

Question 1 of 4

At which layer of the OSI model does a Layer 2 Switch operate and inspect MAC addresses?