Configuring Maximum Information Rate (MIR) Profiles on a RADIUS Server

Maximum Information Rate (MIR) profiles may be created to limit a subscriber module's maximum rate of data transfer - many operators use these profiles to offer differentiated levels of service in their networks.  

These profiles may either be configured separately on each subsciber, or operators may also utilize a RADIUS server in the management network to automatically configure subscriber modules with MIR profiles.  In this case, upon network entry subscriber modules are passed MIR configuration values from the RADIUS server to enact the corresponding rate-limiting.  Examples of interactions between AP GUI MIR settings and RADIUS configuration are detailed in the table below.  This article focuses on creating profiles for an operational RADIUS server.

To begin configuring the MIR profiles, follow these steps:

1.  Create a blank dictionary file which will contain the MIR profiles to be assigned to the subscriber modules:

# touch dictionary.cambium           

2.  Edit dictionary.cambium according to the formatting that you can find under the RADIUS server file /usr/local/etc/raddb/dictionary

For example:

ATTRIBUTE    Cambium-ePMP-ULMB 110            integer   #Max Burst Uplink Rate

ATTRIBUTE   Cambium-ePMP-DLMB 110            integer   #Max Burst Downlink Rate


VENDOR                     Cambium                                         17713



# Cambium vendor-specific attributes.



BEGIN-VENDOR         Cambium


ATTRIBUTE   Cambium-ePMP-ULMB   26            integer   #Max Burst Uplink Rate

ATTRIBUTE   Cambium-ePMP-DLMB   27            integer   #Max Burst Downlink Rate

3.  Create a symbolic link to your custom dictionary file.  This will ensure that the RADIUS server is configured with your profiles when reading file dictionary.local

#ln -s dictionary.cambium dictionary.local

4.  To assign MIR profiles and their corresponding rates to subscribers, edit RADIUS server file usr/local/etc/raddb/users .  Once this file is updated and saved with your custom configuration, upon network entry the rate-limited will be implemented for the subscribers defined in file usr/local/etc/raddb/users . (May require a RADIUS process reset).

For example:

SubscriberModule33 Cleartext-Password := "cambium33"

Cambium-ePMP-ULMB = 100,

Cambium-ePMP-DLMB = 100


SubscriberModule34 Cleartext-Password := "cambium34"

Cambium-ePMP-ULMB = 110,

Cambium-ePMP-DLMB = 110


SubscriberModule35 Cleartext-Password := "cambium35"

Cambium-ePMP-ULMB = 120,

Cambium-ePMP-DLMB = 120

Example scenarios of MIR and RADIUS interactions are described below:



No MIR control via RADIUS

In a scenario where RADIUS is not in use for MIR profiles, the GUI will be the only place to configure MIR profiles and apply them to the corresponding SMs. Configure the MIR profiles in the Configure =-> Quality of Service menu option on the AP GUI and apply the corresponding profile number in the SM under the same menu option on SM.

MIR control using only RADIUS

In the case where only the RADIUS server is being used for MIR profiles, all settings in the GUI will be overridden for any SM being managed by the Radius Server. In this case, create the MIR profile with Subscriber Module usernames and password on the Radius server. At the time of registration, the AP uses the radius information and applies the corresponding profile to the SM. In the wireless statistics page ( => Wireless Status), the MIR profile number from the Radius server along with UL and DL rate information will show up. In this scenario the QOS profiles in the AP GUI are irrelevant. Multiple SMs across multiple APs can then be managed via Radius.

Hybrid control using both RADIUS and MIR profile on the AP GUI

The system also supports a hybrid mode where RADIUS and the GUI QOS profiles can be used simultaneously as long as the same SM does not have a profile number associated from the AP and Radius. In case where it is redundant, the RADIUS server setting will override the MIR profile settings from the GUI.

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