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In this setup, wireless users are separated in different VLANs: VLAN906 for administrative users and VLAN909 for normal eduroam users. The next table describes each VLAN used in this document:

Table 3.1: VLAN description

The next table describes the IP configuration for the router sub-interfaces and what networks are configured for each VLAN:

Table 3.2: Router Configuration

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The next table describes the VLAN associated with each Port of the switch and what equipment will be connected to that specific port.

Table 3.3: Ethernet Switch Configuration

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switch(config)#interface fastethernet0/48
switch(config-if)#switchport trunk encapsulation dot1q
switch(config-if)#switchport trunk native vlan 901
switch(config-if)#switchport trunk allowed vlan 901, 902, 909
switch(config-if)#switchport mode trunk

The following equipment was used for this section:

Cisco AP 1200 Series (802.11g Radio).

The configuration examples used in this document were tested and made on a Cisco Series 1200 with an 802.11g Radio Module and with the following Cisco software:

IOS Version:
Cisco IOS Software, C1200 Software (C1200-K9W7-M), Version 12.3(8)JA2,
RELEASE SOFTWARE (fc1)

Bootloader:
C1200 Boot Loader (C1200-BOOT-M) Version 12.2(8)JA, EARLY DEPLOYMENT RELEASE
SOFTWARE (fc1)

Setting the Name and IP address

First, an IP address on the BVI interface (the IP address that this Access Point will have for accessing
resources like the RADIUS server) needs to be configured. Also a unique name for this Access Point (ap1200)
will be configured.

ap#configure terminal
ap1200(config)#hostname ap1200
ap1200(config)#interface BVI 1
ap1200(config-if)# ip address 192.168.10.200 255.255.255.0

RADIUS/AAA section

In the authentication, authorisation and accounting configuration parameters (AAA), at least one group needs to
be defined (radsrv), which will be assigned later for the several AAA operations. More groups can be defined if
needed for various purposes; one for authentication, another for accounting, and so on. In this example the
RADIUS server has the IP address 192.168.10.253.

ap1200(config)#aaa new-model
ap1200(config)#radius-server host 192.168.10.253 auth-port 1812 acct-port 1813 key <secret>
ap1200(config)#aaa group server radius radsrv
ap1200(config-sg-radius)#server 192.168.10.253 auth-port 1812 acct-port 1813
ap1200(config-sg-radius)#!
ap1200(config-sg-radius)#aaa authentication login eap_methods group radsrv
ap1200(config)#aaa authorization network default group radsrv
ap1200(config)#aaa accounting send stop-record authentication failure
ap1200(config)#aaa accounting session-duration ntp-adjusted
ap1200(config)#aaa accounting update newinfo periodic 15
ap1200(config)#aaa accounting network default start-stop group radsrv
ap1200(config)#aaa accounting network acct_methods start-stop group radsrv

Configuring the SSIDs

For each SSID one dot11 ssid <SSID NAME> must be configured. In this section the default VLAN for the SSID
will be configured as well as the authentication framework, the accounting and, if desired, the SSID to be
broadcast (guest-mode).

ap1200(config)#dot11 ssid eduroam
ap1200(config-ssid)#vlan 909
ap1200(config-ssid)#authentication open eap eap_methods
ap1200(config-ssid)#authentication network-eap eap_methods
ap1200(config-ssid)#authentication key-management wpa optional
ap1200(config-ssid)#accounting acct_methods
ap1200(config-ssid)#guest-mode

More SSIDs can be configured. An open SSID for giving information about the institution and/or how to
connect to the eduroam SSID:

ap1200(config)#dot11 ssid guest
ap1200(config-ssid)#vlan 903
ap1200(config-ssid)#authentication open
ap1200(config-ssid)#accounting acct_methods

The Radio Interface

Now the configured SSID's will be mapped to the radio interface, and it will be specified what ciphers will be
used/allowed on each VLAN. If dynamic VLANs are planned, the ciphers for those VLANs must also be
configured even if there is no direct mapping on any SSID (this example shows the usage of the VLANs 906
and 909 for eduroam users)

ap1200(config)#interface Dot11Radio 0
ap1200(config-if)# encryption vlan 906 mode ciphers aes-ccm tkip wep128
ap1200(config-if)# encryption vlan 909 mode ciphers aes-ccm tkip wep128
ap1200(config-if)#ssid eduroam

To bind extra SSID's the previous command, for each SSID to be bound, needs to be repeated.
The following command sets the maximum time (e.g. 300 seconds, which is recommended) for
rekeying/reauthentication:

dot1x reauth-period 300

VLAN interfaces

For each VLAN to be used for wireless clients, two virtual interfaces need to be defined: one on "the air"
(DotRadio) and another on the "wire" (FastEthernet) then they need to be bridged together with the same
bridge group. These VLANs are always tagged with the proper VLAN identifier.

An administrative VLAN needs to be configured as well (for maintenance/management and
authentication/accounting traffic). This VLAN is usually untagged (the command defining the VLAN has to be
suffixed with the keyword "native") and belongs to bridge-group 1. The Radio virtual interface for this VLAN
does not need to be defined since the default will keep the physical interface (Dot Radio 0) in bridge-group 1.

Because VLANs can be from 1 to 4094 and bridge-groups from 1 to 255, it is not necessary to have the same
bridge-group id as the vlan id.

ap1200(config)#interface dot11Radio 0.903
ap1200(config-subif)#encapsulation dot1Q 903
ap1200(config-subif)#bridge-group 3
ap1200(config)#interface fastEthernet 0.903
ap1200(config-subif)#encapsulation dot1Q 903
ap1200(config-subif)#bridge-group 3
ap1200(config)#interface dot11Radio 0.909
ap1200(config-subif)#encapsulation dot1Q 909
ap1200(config-subif)#bridge-group 9
ap1200(config)#interface fastEthernet 0.909
ap1200(config-subif)#encapsulation dot1Q 909
ap1200(config-subif)#bridge-group 9

The multiple (dynamic) VLAN assignment

The example configuration above did not configure dynamic VLAN assignment. Availability of this feature varies between models of the 1200 Series, so please exercise caution when procuring if you wish to make use of this feature. If multiple VLANs are configured on the Cisco AP, it is mandatory to associate each SSID to at least one VLAN, otherwise the Access Point will not activate the SSID's. It is possible however, to put different users who are connected to the same SSID (e.g. eduroam) on different VLANs based, for instance, on the user profile. To activate this feature it is necessary to enter

 "aaa authorisation network default group radiusgroup"

in the Access Point's configuration. The AP then gives priority to the VLANs returned by RADIUS over the ones statically associated with the SSID. This enables the feature dynamic VLAN assignment.

Cisco's Access Points require that two virtual interfaces (a radio and an Ethernet port interface) are configured for each VLAN. If, for example, four VLANs are to be used for eduroam users (for students, admin staff, teachers and visiting eduroam users from other institutions for example) then it is necessary to define one Dot11Radio0.vlanID, and one FastEthernet0.vlanID, and ensure that both have the same encapsulation dot1Q vlanID and the same bridge-group for each VLAN.

Two commands that are also needed are the below, otherwise the access point will not change the user to the received VLAN:

encryption vlan vlanID mode ciphers aes-ccm

broadcast-key vlan vlanID change 600 membership-termination capability-change

Sample configuration

The required configuration can be downloaded as a file fromhttp://www.eduroam.org/downloads/docs/eduroam-cookbook-scripts.zip. You must then amend the file as indicated by the comments in the file, and then copy and paste the commands into the Access Point in configuration mode (telnet or console access).

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