How do I implement rate-limiting at the SM for large network deployments?

ePMP Rate-Limiting via MIR (Maximum Information Rate) Profiles

The limiting of data rates at the SM is achieved by configuring the MIR Profiles table on the AP and assigning these profile IDs to the SMs by using the SM configuration parameter MIR Profile Setting.  Operators may add up to 16 MIR profiles on the AP, each with unique limits for uplink and downlink data rates.

As your ePMP networks grow, it may become more efficient to manage MIR profile settings in a centralized RADIUS server in the management network.  Operators may configure the RADIUS server to automatically provide MIR profile rate-limiting configurations to new SMs deployed into the network instead of configuring each SM MIR profile setting individually.

Configuring MIR Profiles on a RADIUS Server

To configure the MIR profiles, follow these steps:

  • Create a dictionary file with the MIR Profiles:

# touch dictionary.cambium          

  • Edit cambium according to the instructions that you can find under /usr/local/etc/raddb directory in file 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


  • Create link on your dictionary:

#ln -s dictionary.cambium dictionary.local

  • To configure MIR profiles, edit usr/local/etc/raddb/users and add profiles for each client below users configuration :

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

A few example scenarios of MIR and RADIUS configurations 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 # 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 # 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 # associated from the AP & Radius. In case where it is redundant, Radius server setting will override the MIR profile settings from the GUI.

For information regarding the configuration of a RADIUS server for operation in an ePMP network, please see section "Radius Server" in the ePMP User Guide.