Network engineering workspace
Plan it once. Generate it everywhere.
NetField turns device counts into a validated addressing plan and vendor-ready configuration — then checks it for the mistakes that take production down.
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One plan, seven platforms
The same intent, in each platform's own syntax
Three segments across 10.20.0.0/16, 1,786 usable addresses. Switch platform — the addressing does not change, only the commands.
! Cisco IOS / IOS-XE — generated by NetField
! 3 VLANs
! Review before applying. Interface names and trunk membership are site-specific.
configure terminal
!
vlan 10
name GUEST_WIFI
!
interface Vlan10
description GUEST_WIFI - 600 devices
ip address 10.20.0.1 255.255.252.0
no shutdown
!
ip dhcp excluded-address 10.20.0.0 10.20.0.12
ip dhcp pool GUEST_WIFI
network 10.20.0.0 255.255.252.0
default-router 10.20.0.1
dns-server 8.8.8.8
!
vlan 11
name CLINICAL
!
interface Vlan11
description CLINICAL - 420 devices
ip address 10.20.4.1 255.255.254.0
no shutdown
!
ip dhcp excluded-address 10.20.4.0 10.20.4.12
ip dhcp pool CLINICAL
network 10.20.4.0 255.255.254.0
default-router 10.20.4.1
dns-server 8.8.8.8
!
vlan 12
name VOIP
!
interface Vlan12
description VOIP - 240 devices
ip address 10.20.6.1 255.255.255.0
no shutdown
!
ip dhcp excluded-address 10.20.6.0 10.20.6.12
ip dhcp pool VOIP
network 10.20.6.0 255.255.255.0
default-router 10.20.6.1
dns-server 8.8.8.8
!
interface GigabitEthernet0/1
switchport mode trunk
switchport trunk allowed vlan 10,11,12
!
end
write memoryEach platform is a translation, not a template substitution — Cisco writes sequential lists, Juniper writes terms, FortiGate writes zone policies against named objects, RouterOS writes chain rules. The intent is shared; the syntax is not.
The problem
A VLAN plan should not take ten tabs
Subnet arithmetic in one window, vendor syntax in another, the addressing plan in a spreadsheet nobody else can find. Every project repeats the same calculations, and every calculation is a chance to typo a mask.
- Subnet calculator
- Spreadsheet
- Visio
- Notepad
- Cisco docs
- Juniper docs
- MikroTik wiki
- Firewall manual
- Terminal
- Search
A single mistyped mask can take down production. The arithmetic is deterministic — it should not be done by hand.
Vendor platforms
Cisco IOS and NX-OS, Juniper, MikroTik, Aruba, Fortinet, Ubiquiti.
Validation checks
Structural faults caught before a change window, not during one.
Calculators
Addressing, encapsulation, power and link budgets — all offline.
Documented commands
With per-vendor syntax, examples and the mistakes that cost time.
Capabilities
The whole path, in one place
Design, generate, validate, document. Every step is deterministic — the same inputs always produce the same plan. Pick one to see what it actually produces.
VLSM addressing
Device counts in, a contiguous plan out. Blocks are allocated largest-first so nothing strands unusable gaps, and each is sized for the gateway as well as the hosts.
VLAN 11 Clinical 10.20.4.0/23 gw 10.20.4.1 dhcp 10.20.4.12 – 10.20.5.254
VLAN 10 Guest WiFi 10.20.0.0/22 gw 10.20.0.1 dhcp 10.20.0.12 – 10.20.3.254
VLAN 12 VoIP 10.20.6.0/24 gw 10.20.6.1 dhcp 10.20.6.12 – 10.20.6.254Validation
Find it before the change window
Paste a configuration and it is parsed, not pattern-matched. Duplicate addresses, overlapping DHCP scopes, VLANs referenced but never created, ACLs applied but never defined, next hops nothing can reach.
VLAN 10 is used but never declared
Referenced by Vlan10 but there is no "vlan 10" statement. On most platforms the VLAN will not be created and traffic will be dropped.
Duplicate IP address 10.0.10.1
Configured on both Vlan10 (line 1) and Vlan20. One of the two interfaces will fail to come up.
Overlapping subnets on different interfaces
Vlan10 (10.0.10.0/24) overlaps Vlan20 (10.0.10.0/24). Routing between them is ambiguous.
Actual output from the validator, run against a four-interface config with three deliberate faults.
Support
Ask an engineer, not a bot
Questions about a generated config, a vendor syntax correction, or something that behaved differently on real hardware — all of it is useful.
Vendor syntax corrections are the most valuable thing you can send. Every emitter is written from documentation, and documentation and hardware disagree more often than either would like.
Please do not paste a production configuration containing live credentials. The validator runs entirely in your browser if you need to check one privately.
Start with the arithmetic. Keep the judgement.
NetField does the deterministic part — the masks, the boundaries, the syntax, the cross-checks. What to build, and whether to deploy it, stays with you.