Example: Setting Up VoIP with 802.1X and LLDP-MED on an EX Series Switch

Requirements

This example uses the following hardware and software components:

• Junos OS Release 9.1 or later for EX Series switches
• One EX Series switch acting as an authenticator port access entity (PAE). The interfaces on the authenticator PAE form a control gate that blocks all traffic to and from supplicants until they are authenticated.
• An Avaya 9620 IP telephone that supports LLDP-MED and 802.1X

Before you configure VoIP, be sure you have:

• Installed the switch. See the installation instructions for your switch.
• Performed the initial switch configuration. See Connecting and Configuring an EX Series Switch (J-Web Procedure).
• Performed basic bridging and VLAN configuration on the switch. See Example: Setting Up Basic Bridging and a VLAN for an EX Series Switch.
• Configured the RADIUS server for 802.1X authentication and set up the access profile. See Example: Connecting a RADIUS Server for 802.1X to an EX Series Switch.
• (Optional) Configured interface ge-0/0/2 for Power over Ethernet (PoE). The PoE configuration is not necessary if the VoIP supplicant is using a power adapter. For information about configuring PoE, see Configuring PoE (CLI Procedure).

Note: If the IP address isn't configured on the Avaya IP phone, the phone exchanges LLDP-MED information to get the VLAN ID for the voice VLAN. You must configure the voip statement on the interface to designate the interface as a VoIP interface and allow the switch to forward the VLAN name and VLAN ID for the voice VLAN to the IP telephone. The IP telephone then uses the voice VLAN (that is, it references the voice VLAN’s ID) to send a DHCP discover request and exchange information with the DHCP server (voice gateway).

Overview and Topology

Instead of using a regular telephone, you connect an IP telephone directly to the switch. An IP phone has all the hardware and software needed to handle VoIP. You also can power an IP telephone by connecting it to one of the Power over Ethernet (PoE) interfaces on the switch.

In this example, the access interface ge-0/0/2 on the EX4200 switch is connected to an Avaya 9620 IP telephone. Avaya phones have a built-in bridge that allows you to connect a desktop PC to the phone, so the desktop and phone in a single office require only one interface on the switch. The EX Series switch is connected to a RADIUS server on interface ge-0/0/10 (see Figure 1).

Figure 1: VoIP Topology

In this example, you configure VoIP parameters and specify the forwarding class assured-forward for voice traffic to provide the highest quality of service.

Table 1 describes the components used in this VoIP configuration example.

As well as configuring a VoIP for interface ge-0/0/2, you configure:

• 802.1X authentication. Authentication is set to multiple supplicant to support more than one supplicant's access to the LAN through interface ge-0/0/2.
• LLDP-MED protocol information. The switch uses LLDP-MED to forward VoIP parameters to the phone. Using LLDP-MED ensures that voice traffic gets tagged and prioritized with the correct values at the source itself. For example, 802.1p class of service and 802.1Q tag information can be sent to the IP telephone.

  Note: A PoE configuration is not necessary if an IP telephone is using a power adapter.

Configuration

To configure VoIP, LLDP-MED, and 802.1X authentication:

CLI Quick Configuration

To quickly configure VoIP, LLDP-MED, and 802.1X, copy the following commands and paste them into the switch terminal window:

Step-by-Step Procedure

To configure VoIP with LLDP-MED and 802.1X:

1. Configure the VLANs for voice and data:
   
   

   [edit vlans]
user@switch# set data-vlan vlan-id 77
user@switch# set voice-vlan vlan-id 99
2. Associate the VLAN data-vlan with the interface:
   
   

   [edit vlans]
user@switch# set data-vlan interface ge-0/0/2.0

3. Configure the interface as an access interface, configure support for Ethernet switching, and add the data-vlan VLAN:
   
   

   [edit interfaces]
user@switch# set ge-0/0/2 unit 0 family ethernet-switching vlan members data-vlan
user@switch# set ge-0/0/2 unit 0 family ethernet-switching port-mode access
4. Configure VoIP on the interface and specify the assured-forwarding forwarding class to provide the most dependable class of service:
   
   

   [edit ethernet—switching—options]
user@switch# set voip interface ge-0/0/2.0 vlan voice-vlan
user@switch# set voip interface ge-0/0/2.0 forwarding-class assured-forwarding

5. Configure LLDP-MED protocol support:
   
   

   [edit protocols]
user@switch# set lldp-med interface ge-0/0/2.0

6. To authenticate an IP phone and a PC connected to the IP phone on the interface, configure 802.1X authentication support and specify multiple supplicant mode:

   Note: If you do not want to authenticate any device, skip the 802.1X configuration on this interface.

   
   

   [edit protocols]
user@switch# set dot1x authenticator interface ge-0/0/2.0 supplicant multiple

Results

Display the results of the configuration:

Verification

To confirm that the configuration is working properly, perform these tasks:

• Verifying LLDP-MED Configuration
• Verifying 802.1X Authentication for IP Phone and Desktop PC
• Verifying the VLAN Association with the Interface

Verifying LLDP-MED Configuration

Purpose

Verify that LLDP-MED is enabled on the interface.

Action

LLDP                   : Enabled
Advertisement interval : 30 Second(s)
Transmit delay         : 2 Second(s)
Hold timer             : 2 Second(s)
Config Trap Interval   : 300 Second(s)
Connection Hold timer  : 60 Second(s)

LLDP MED               : Enabled
MED fast start count   : 3 Packet(s)


Interface      LLDP       LLDP-MED    Neighbor count
all            Enabled    -           0         
ge-0/0/2.0     -          Enabled     0         

Interface     VLAN-id     VLAN-name
ge-0/0/0.0    0           default  
ge-0/0/1.0    0           employee-vlan
ge-0/0/2.0    0           data-vlan
ge-0/0/2.0    99          voice-vlan
ge-0/0/3.0    0           employee-vlan
ge-0/0/8.0    0           employee-vlan
ge-0/0/10.0   0           default  
ge-0/0/11.0   20          employee-vlan
ge-0/0/23.0   0           default  

LLDP basic TLVs supported: 
Chassis identifier, Port identifier, Port description, System name, System
description, System capabilities, Management address.

LLDP 802 TLVs supported: 
Power via MDI, Link aggregation, Maximum frame size, Port VLAN tag, Port
VLAN name.

LLDP MED TLVs supported: 
LLDP MED capabilities, Network policy, Endpoint location, Extended power
Via MDI.

Meaning

The show lldp detail output shows that both LLDP and LLDP-MED are configured on the ge-0/0/2.0 interface. The end of the output shows the list of supported LLDP basic TLVs, 802.3 TLVs, and LLDP-MED TLVs that are supported.

Verifying 802.1X Authentication for IP Phone and Desktop PC

Purpose

Display the 802.1X configuration to confirm that the VoIP interface has access to the LAN.

Action

ge-0/0/2.0
  Role: Authenticator
  Administrative state: Auto
  Supplicant mode: Multiple
  Number of retries: 3
  Quiet period: 60 seconds
  Transmit period: 30 seconds
  Mac Radius: Disabled
  Mac Radius Restrict: Disabled
  Reauthentication: Enabled
  Configured Reauthentication interval: 3600 seconds
  Supplicant timeout: 30 seconds
  Server timeout: 30 seconds
  Maximum EAPOL requests: 2
  Guest VLAN member: <not configured>
  Number of connected supplicants: 1
    Supplicant: user101, 00:04:0f:fd:ac:fe
      Operational state: Authenticated
      Authentication method: Radius
      Authenticated VLAN: vo11
      Dynamic Filter: match source-dot1q-tag 10 action deny
      Session Reauth interval: 60 seconds
      Reauthentication due in 50 seconds

Meaning

The field Role shows that the ge-0/0/2.0 interface is in the authenticator state. The Supplicant field shows that the interface is configured in multiple supplicant mode, permitting multiple supplicants to be authenticated on this interface. The MAC addresses of the supplicants currently connected are displayed at the bottom of the output.

Verifying the VLAN Association with the Interface

Purpose

Display the interface state and VLAN membership.

Action

 Ethernet-switching table: 0 entries, 0 learned

user@switch> show ethernet-switching interfaces 
Interface   State    VLAN members           Blocking 
ge-0/0/0.0  down     default                unblocked
ge-0/0/1.0  down     employee-vlan          unblocked
ge-0/0/5.0  down     employee-vlan          unblocked
ge-0/0/3.0  down     employee-vlan          unblocked
ge-0/0/8.0  down     employee-vlan          unblocked
ge-0/0/10.0 down     default                unblocked
ge-0/0/11.0 down     employee-vlan          unblocked
ge-0/0/23.0 down     default                unblocked
ge-0/0/2.0  up       voice-vlan             unblocked
                     data-vlan              unblocked

Meaning

The field VLAN members shows that the ge-0/0/2.0 interface supports both the data-vlan VLAN and voice-vlan VLAN. The State field shows that the interface is up.