General Structure
Rules allow further restrictions

Rule Collection
Every Rule can have a Name, Description and is specified for a specific authentication type. Currently you can define a rule for Wi-Fi, LAN and VPN. Furthermore, you can Enable or Disable each rule.
The Rules tab lists every configured rule, its position, its type (Wi-Fi, LAN, VPN or Generic Allow), its name and description, the authentication method it accepts, the filters it applies to, what it grants, and whether it is enabled.
Creating a Rule
Clicking Add rule lets you pick a medium: Generic Allow, Wi-Fi, LAN, or VPN.
Choosing Wi-Fi, LAN or VPN opens a guided four-step wizard. A live "in plain words" summary at the bottom of the dialog rephrases the rule in plain language as it is built, for example:
IN PLAIN WORDS
A Wi-Fi request authenticating with certificate only from CN=SCEPman-SaaS-CA,O=Contoso matching Cert Subject (DN) matches OU=Printers is granted VLAN 16 (static).
The following steps show the rule editor with a simple example of the above description:
Who may authenticate (Authentication Methods)
Turn on Certificate-based and/or Username/Password-based authentication; at least one must be enabled. Enabling certificates reveals an optional Restrict root certificates toggle, which narrows the rule down to specific Trusted Roots instead of accepting any certificate trusted by the platform.

Where it applies (Filters)
Filters narrow the rule down and are combined with AND, meaning a request must satisfy every filter listed; leaving this step empty means the rule applies everywhere. The filters on offer depend on the medium, and each filter can take individual values or reference a reusable Group. See the Wi-Fi, LAN and VPN sections below for the specific filters each medium offers and a worked example.

What it grants (Assignments)
Defines the access returned when the rule matches: a VLAN and/or additional RADIUS attributes, each either Static (a fixed value) or Dynamic. Dynamic assignment reads a value out of the certificate, from its Issuer, SAN, DN, or a custom Extension, applies a regex pattern to it, and maps the result to the value that gets granted. This same regex mechanism is also used for Certificate Attribute filters in Step 3. You can also define what happens if no pattern matches: reject the request, or fall back to a default value.

Authentication Methods
The authentication methods you can define in "Who may authenticate" restricts the technical medium an authentication needs to use to be accepted.
Certificate-based authentication
You can either enable CBA alone to match all such authentications or further limit authentications for certificates signed by specific CAs.

Username/Password-based authentication
Enable this method to allow authentications that do not use certificate-based authentication.

Filters
Filters can be used to build granular rules that match only under certain circumstances. There are multiple available filters that can be used in different situations:
Available for all Rules
Client IPs
Certificate Attributes
Username/Password
Intune IDs
Available for specific Rules
SSIDs (Wi-Fi Rules)
Switch MACs (LAN Rules)
NAS Identitfiers (VPN Rules)
NAS IPs (VPN Rules)
Client IPs
Use the Client IPs filter to match a rule on the WAN-IP address of the authentications. You can use single addresses, CIDRs or a defined group.

Certificate Attributes
Use this filter type to match a rule only if a presented client certificate contains the required information. You can filter for the following attributes:
Issuer
SAN (Subject Alternative Name)
DN (Distinguished Name)
Extension

Examples:
Use a SAN filter
.*-ext@contoso\.com$to matchjohn.smith-ext@contoso.com→ contractor identity cert, VLAN 10.Use a DN
OU=Printersto match the subjectCN=PRINTER07,OU=Printers,O=Contoso→ assign VLAN 16 (printers).Use a DN
OU=Financeto match the subjectCN=jdoe,OU=Finance,O=Contoso→ VLAN 30 (Finance).Use a SAN filter
^platform:windows$to match specific platforms. Use an URI SAN with value ofplatform:windowsto match this.
Username/Password

Examples:
Username
^ext-.*matchesext-jsmith→ VLAN 50 (contractor)Owner
IT-AssetPoolmatches shared/kiosk device tag → Filter-Idkiosk-acl
SSIDs
To filter for SSIDs, you can choose to match single SSIDs per entry or add a defined group of SSIDs.

Switch MACs
To filter for Switch MACs, you can choose to match single address per entry or add a defined group of Switch MACs.

NAS-Identifiers
Similar to other filters, you can choose to match single NAS-Identifiers per entry or add a defined group of NAS-Identifiers.
NAS IPs
Similar to other filters, you can choose to match single NAS-IPs per entry or add a defined group of NAS-IPs.
Intune IDs
This is a historical filter. If your clients are authenticating with certificates that your clients received during the AAD-Join, you want to filter for your Intune Tenant ID.
In case you have entered your Tenant IDs as described here, the default behaviour of RADIUSaaS is that only machines presenting a certificate with extension OID 1.2.840.113556.5.14 and a whitelisted value for the Tenant ID will get access to the network. With the rule engine, you now have the option to further restrict the access to specific Intune IDs for a specific rule or to ignore the certificate extension. This allows you to have a multi-deployment setup, where some clients come with certificates providing the respective OID and some do not.

Assignments
If an authentication is valid and matches a rule, the returned Access-Accept packet can contain specific information to give further instructions to the authenticator.
VLAN
A VLAN ID can be assigned statically, meaning that all matching authentications will receive this VLAN ID, or dynamically by extracting the desired value from either a certificate attribute or the username/owner.
By Certificate Subject (DN)
You can also assign VLAN IDs based on properties in the Subject Name of your certificate
Therefore, specify in which property the VLAN ID is stored
Then, configure which string the VLAN ID is prefixed with
The VLAN ID is not required to have a prefix. However, it can be required to use a prefix in case your Subject Name carries the same attribute more than once (e.g. several CN's are quite common).
As an example, the following assignment will match the DN attribute of the client certificate using the regex pattern OU=vlan-(\d+) and use the first matching group as resulting value.
For a certificate subject (DN) of CN=CLIENT01,OU=vlan-15 this result in a VLAN assignment of 15.

By Certificate Extension
Select one of your created Certificate Extensions
Choose a regex pattern to get the desired value

Attributes
RADIUS return attributes allow network administrators to define specific settings for individual users or groups.
For example,
For User Profile Configuration, an attribute can specify the maximum session duration, allowed services (such as VPN or Wi-Fi), and IP address assignment method.
For Dynamic IP Address Assignment, an attribute might specify that the user should receive a static IP address or use DHCP for dynamic assignment.
For Access Control and Authorization, an attribute determines the user’s access level (e.g., guest, employee, administrator) and any restrictions (e.g., time limits).
For Session Management, an attribute can specify session timeout (how long the user can stay connected), idle timeout (disconnect after inactivity), and maximum simultaneous logins.
For Quality of Service (QoS), an attribute might prioritize voice traffic over data traffic for a specific user.
Vendors can create their own custom attributes (vendor-specific attributes or VSAs). These allow for additional functionality beyond the standard IETF attributes. VSAs are encapsulated within the standard attribute 26.
In the same manner of VLAN assignments, attributes can be returned either statically or dynamically.
You can choose from different return attributes and extend them in the attribute catalogue:
Example:
Dynamically assign the value of the certificates RDN L to the the return attribute Filter-Id

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