iPSK subnet designer: Multi-tenant WiFi and DHCP scope calculator
Design private RFC 1918 IPv4 subnets, dynamic VLAN IDs, and DHCP pools for MDU and student housing using Identity Pre-Shared Keys.
Plan multi-tenant subnet allocation and DHCP scopes
1. Base IP address block
Enter the starting private IPv4 subnet block (RFC 1918) for the building estate.
2. Number of units
3. Expected devices per unit
10 Devices4. Starting VLAN ID
Base VLAN tag for 802.1Q trunkingSizing 100 units with up to 10 devices each requires 16 IPs per unit (/28 subnet). Your parent pool reserves 2,048 total IP addresses.
Subnet allocation map preview (First 6 of 100 units)
Download the full CSV or JSON file above to obtain all 100 unit records.
| Unit identifier | Subnet CIDR | Gateway IP | Usable DHCP pool range | Broadcast IP | VLAN ID |
|---|---|---|---|---|---|
| Apartment 1 | 10.0.0.0/28 | 10.0.0.1 | 10.0.0.2 - 10.0.0.14 | 10.0.0.15 | VLAN 101 |
| Apartment 2 | 10.0.0.16/28 | 10.0.0.17 | 10.0.0.18 - 10.0.0.30 | 10.0.0.31 | VLAN 102 |
| Apartment 3 | 10.0.0.32/28 | 10.0.0.33 | 10.0.0.34 - 10.0.0.46 | 10.0.0.47 | VLAN 103 |
| Apartment 4 | 10.0.0.48/28 | 10.0.0.49 | 10.0.0.50 - 10.0.0.62 | 10.0.0.63 | VLAN 104 |
| Apartment 5 | 10.0.0.64/28 | 10.0.0.65 | 10.0.0.66 - 10.0.0.78 | 10.0.0.79 | VLAN 105 |
| Apartment 6 | 10.0.0.80/28 | 10.0.0.81 | 10.0.0.82 - 10.0.0.94 | 10.0.0.95 | VLAN 106 |
Wireless controller configuration generator
Select your network hardware stack to produce ready-to-deploy CLI commands and JSON profiles.
# Cisco Meraki MX Security Appliance DHCP & Dynamic VLAN Configuration
# Property Profile: Multi-Tenant Residential WiFi (VLANs 101 to 200)
# WPA2 / WPA3 Enterprise SSID with Identity Pre-Shared Keys (iPSK)
# RADIUS Dynamic VLAN Attribute: Tunnel-Private-Group-ID
# Sample per-unit DHCP scopes (Units 1 to 6):
vlan_101:
name: "Apartment_1"
id: 101
appliance_ip: "10.0.0.1"
subnet: "10.0.0.0/28"
netmask: "255.255.255.240"
dhcp_handling: "Run a DHCP server"
dhcp_lease_time: "1 day"
dhcp_start: "10.0.0.2"
dhcp_end: "10.0.0.14"
dns_nameservers: "custom"
custom_dns: ["1.1.1.1", "8.8.8.8"]
client_isolation: true
vlan_102:
name: "Apartment_2"
id: 102
appliance_ip: "10.0.0.17"
subnet: "10.0.0.16/28"
netmask: "255.255.255.240"
dhcp_handling: "Run a DHCP server"
dhcp_lease_time: "1 day"
dhcp_start: "10.0.0.18"
dhcp_end: "10.0.0.30"
dns_nameservers: "custom"
custom_dns: ["1.1.1.1", "8.8.8.8"]
client_isolation: true
vlan_103:
name: "Apartment_3"
id: 103
appliance_ip: "10.0.0.33"
subnet: "10.0.0.32/28"
netmask: "255.255.255.240"
dhcp_handling: "Run a DHCP server"
dhcp_lease_time: "1 day"
dhcp_start: "10.0.0.34"
dhcp_end: "10.0.0.46"
dns_nameservers: "custom"
custom_dns: ["1.1.1.1", "8.8.8.8"]
client_isolation: true
vlan_104:
name: "Apartment_4"
id: 104
appliance_ip: "10.0.0.49"
subnet: "10.0.0.48/28"
netmask: "255.255.255.240"
dhcp_handling: "Run a DHCP server"
dhcp_lease_time: "1 day"
dhcp_start: "10.0.0.50"
dhcp_end: "10.0.0.62"
dns_nameservers: "custom"
custom_dns: ["1.1.1.1", "8.8.8.8"]
client_isolation: true
vlan_105:
name: "Apartment_5"
id: 105
appliance_ip: "10.0.0.65"
subnet: "10.0.0.64/28"
netmask: "255.255.255.240"
dhcp_handling: "Run a DHCP server"
dhcp_lease_time: "1 day"
dhcp_start: "10.0.0.66"
dhcp_end: "10.0.0.78"
dns_nameservers: "custom"
custom_dns: ["1.1.1.1", "8.8.8.8"]
client_isolation: true
vlan_106:
name: "Apartment_6"
id: 106
appliance_ip: "10.0.0.81"
subnet: "10.0.0.80/28"
netmask: "255.255.255.240"
dhcp_handling: "Run a DHCP server"
dhcp_lease_time: "1 day"
dhcp_start: "10.0.0.82"
dhcp_end: "10.0.0.94"
dns_nameservers: "custom"
custom_dns: ["1.1.1.1", "8.8.8.8"]
client_isolation: true
Multi-tenant network design for residential property operators
Identity Pre-Shared Keys (iPSK) and Private Pre-Shared Keys (PPSK) enable multi-dwelling properties to broadcast a single SSID while dynamically isolating each resident's devices into their own private VLAN. This designer helps network engineers size the parent CIDR block, define per-unit DHCP pools, and generate configuration commands for enterprise wireless controllers.
Core multi-tenant design parameters
- Dynamic VLAN steering per residential unit for smart TVs, games consoles, and IoT devices.
- DHCP scope sizing and lease duration optimization to prevent IP address exhaustion.
- Automated configuration script generation for Cisco Meraki, HPE Aruba Central, Ruckus SmartZone, Juniper Mist, and Extreme Networks.
The WiFi bubble architecture for multi-tenant housing
Modern residential developments - including Build to Rent (BTR), Purpose-Built Student Accommodation (PBSA), senior living, and social housing - require seamless property-wide connectivity without compromising resident privacy. Broadcasting individual SSIDs per apartment causes severe 2.4 GHz and 5 GHz channel congestion, while a single shared WPA2 password exposes devices to neighbors on the same Layer 2 broadcast domain.
The WiFi Bubble architecture solves this dilemma. A single property-wide SSID is broadcast across all enterprise access points. When a tenant authenticates using their unique Identity Pre-Shared Key (iPSK) or Private Pre-Shared Key (PPSK), the wireless controller consults a cloud RADIUS server and assigns the client to their dedicated private VLAN. Smart TVs, gaming consoles, Apple AirPlay streamers, and laptops communicate securely within the apartment bubble while remaining isolated from other residents.
Explore our comprehensive framework on resident onboarding, operational economics, and IoT device management in the Multi-Tenant WiFi Guide. For enterprise authentication mechanics, review the Enterprise WiFi Security Guide.
Subnet sizing and CIDR prefix allocation benchmarks
Selecting the correct subnet mask per apartment balances host capacity against IP address consumption. Use these sizing benchmarks to plan your parent network allocation across multi-dwelling buildings:
| Unit count | Max devices/unit | Per-unit CIDR mask | Usable hosts/unit | Parent network CIDR | Total parent IPs |
|---|---|---|---|---|---|
| 25 Units (Boutique BTR) | Up to 5 devices | /29 (255.255.255.248) | 6 hosts | /24 (256 IPs) | 256 addresses |
| 50 Units (Student Block) | Up to 13 devices | /28 (255.255.255.240) | 14 hosts | /22 (1,024 IPs) | 1,024 addresses |
| 100 Units (Standard MDU) | Up to 13 devices | /28 (255.255.255.240) | 14 hosts | /21 (2,048 IPs) | 2,048 addresses |
| 250 Units (Large Residential) | Up to 29 devices | /27 (255.255.255.224) | 30 hosts | /19 (8,192 IPs) | 8,192 addresses |
| 500 Units (Urban Campus) | Up to 29 devices | /27 (255.255.255.224) | 30 hosts | /18 (16,384 IPs) | 16,384 addresses |
Multi-tenant wireless authentication comparison
Evaluating wireless authentication methods for multi-dwelling residential buildings requires balancing IoT device compatibility against administrative complexity and security:
| Authentication architecture | IoT & Smart TV support | Layer 2 isolation | Client onboarding experience | Controller support |
|---|---|---|---|---|
| iPSK / PPSK (Recommended) | Native WPA2/WPA3-Personal passkey. 100% compatible with headless smart devices. | Automated dynamic VLAN steering per key. Complete inter-tenant isolation. | Frictionless. Resident enters key once; smart devices discover local bubble. | Cisco Meraki, HPE Aruba, Ruckus, Juniper Mist, Extreme. |
| 802.1X Enterprise (EAP-TLS/PEAP) | Poor. Most smart plugs, game consoles, and streaming sticks lack 802.1X supplicants. | Dynamic VLAN assignment via RADIUS Tunnel attributes. | Requires certificate installation or username/password entry. High support tickets. | Universal across enterprise hardware. |
| Captive Portal Web Login | Incompatible with headless IoT without MAC authentication bypass. | Client isolation or shared guest subnet. No local device communication. | Browser pop-up required on connect. Ideal for visitors, poor for permanent residents. | Supported via Purple Cloud integrations. |
| Shared WPA2/WPA3 Pre-Shared Key | Native compatibility. | Zero isolation. All residents share the same broadcast domain (Chromecast hijacking risk). | Simple entry, but impossible to revoke a single departing tenant without re-keying all. | Consumer and enterprise APs. |
Enterprise controller implementation blueprints
Deploying multi-tenant identity keys requires configuring dynamic VLAN tags and RADIUS authorization on your wireless infrastructure:
Enable iPSK with RADIUS authentication on the MR access point SSID. The RADIUS server returns Tunnel-Private-Group-ID to dynamically place the device into the tenant VLAN routed by the MX Security Appliance.
Configure Cloud Authentication and Dynamic PSK on Aruba Central. User roles map each unique passphrase to local VLAN subnets and apply role-based access control policies at the AP edge.
Generate per-user DPSKs bound to tenant VLAN tags. Ruckus Virtual SmartZone handles encryption key matching locally and steers traffic directly into the corresponding Virtual Ethernet (VE) interface.
Mist AI provisions dynamic PSKs via API. Each resident key enforces client isolation, dynamic VLAN assignment, and per-resident bandwidth rate limiting without complex on-premise controllers.
DHCP scope and lease time engineering best practices
DHCP misconfiguration is the leading cause of connectivity failures in dense multi-tenant residential networks. Follow these engineering guidelines when deploying per-unit subnets:
Because resident devices remain on site for months, 24-hour DHCP lease times (86,400 seconds) minimize DHCP broadcast traffic and reduce CPU load on core gateway switches. For visitor or public common area SSIDs, use 2 to 4 hour leases to recycle transient MAC addresses.
Ensure switches are configured with DHCP snooping on access ports to prevent rogue DHCP servers (such as a resident accidentally connecting a consumer router backwards into an Ethernet wall jack).
iOS and Android rotate private MAC addresses by default. Allocating at least a /28 subnet (14 usable IPs) per apartment prevents pool exhaustion when residents own multiple devices that generate rotated MAC addresses.
Everything you need to know about multi-tenant iPSK subnet design
What is an Identity Pre-Shared Key (iPSK) and how does it work in multi-tenant housing?
Identity Pre-Shared Key (iPSK), also known as Private Pre-Shared Key (PPSK), allows multiple clients to connect to the same SSID using distinct, unique passphrases. When a resident connects with their assigned key, the access point queries a cloud RADIUS server, which returns the resident's specific VLAN tag (Tunnel-Private-Group-ID). This places all devices belonging to that resident onto an isolated Layer 2 broadcast domain, enabling seamless local discovery between their smart TV, phone, and laptop without exposing them to other building residents.
What is the difference between iPSK and PPSK?
iPSK (Identity Pre-Shared Key) and PPSK (Private Pre-Shared Key) refer to the same underlying architectural concept implemented under different vendor trademarks. Cisco Meraki and Juniper Mist use the term iPSK, while Extreme Networks, Ruckus (DPSK), and HPE Aruba (Dynamic PSK) use variations of PPSK/DPSK. All achieve the same outcome: mapping individual passphrases to specific VLANs and security policies over standard WPA2/WPA3-Personal protocols.
How do I choose the correct subnet mask size per residential unit?
For typical 1-bedroom or 2-bedroom apartments, a /28 subnet (255.255.255.240) provides 14 usable host addresses, accommodating laptops, smartphones, smart TVs, gaming consoles, and IoT hubs with safety buffer for MAC address randomization. For studio student units with 5 or fewer devices, a /29 subnet (6 usable hosts) conserves IP space. For large 3 to 4-bedroom penthouses or communal apartments with heavy IoT deployment, a /27 subnet (30 usable hosts) is recommended.
Why is client isolation and dynamic VLAN assignment necessary on shared residential networks?
On a traditional single-password WiFi network, all connected devices reside on the same broadcast domain. This allows malicious or curious neighbors to discover local network shares, hijack Chromecast/AirPlay video streams, access unencrypted smart home cameras, and intercept multicast packets. Dynamic VLAN assignment isolates each apartment into a dedicated private broadcast domain, providing home-like security across a commercial infrastructure.
How does Purple automate iPSK provisioning across enterprise hardware?
Purple Connect integrates directly with property management software (PMS) to generate unique iPSK passkeys automatically when a lease is signed. Through cloud RADIUS integrations with Cisco Meraki, HPE Aruba, Ruckus, and Juniper Mist, Purple dynamically assigns the correct VLAN tag, enforces bandwidth tiers, and revokes credentials instantly when a tenant moves out, eliminating manual IT overhead.
Deploying multi-tenant resident WiFi?
Purple automates resident onboarding, identity key generation, and private VLAN isolation across Cisco Meraki, Aruba, Ruckus, and Juniper Mist. Book a 20-minute architecture review.
Book a 20-min demoNetforge Network Multi-Tool
Run offline network health checks, path analysis, and latency diagnostic scans directly from your desktop.
Download Multi-Tool