Configuring the Device for Skype for Business Presence

The following procedure describes how to configure the device for notifying Skype for Business Server of presence status of Skype for Business users when making and receiving calls using third-party, endpoint devices. To help you understand the configuration, the following lists in chronological order the main processing steps:

1. The device receives an incoming call.
2. The device uses a Call Setup Rule to perform LDAP queries on the Microsoft Active Directory to retrieve Skype for Business usernames (Request URIs) for the corresponding calling (source) and/or called (destination) number. For SBC calls, the Call Setup Rule is associated with the classified source IP Group (in the IP Groups table).
3. The device routes the call to the required destination, according to the normal routing rules.
4. When the call is connected, the device sends a SIP PUBLISH message to Skype for Business Server, indicating that the users' presence status is now "On-the-Phone".
5. When the call ends, the device sends another SIP PUBLISH message to the Skype for Business Server, clearing the users' "On-the-Phone" status (the presence status changes to what it was before the call was connected).
To configure the device for Skype for Business presence:
1. Enable the Microsoft presence feature: open the SIP Definitions General Settings page (Setup menu > Signaling & Media tab > SIP Definitions folder > SIP Definitions General Settings), and then from the 'Microsoft Presence Status' drop-down list, select Enable:

2. Configure a TLS Context (TLS certificate) for secured communication (mutual authentication) between the device and the Skype for Business Server (see Configuring TLS Certificate Contexts).
3. Configure a Proxy Set to define the address of the Skype for Business Server (see Configuring Proxy Sets). Make sure you configure the following:
'TLS Context Name': Assign the TLS Context that you configured in Step 2 (above).
'Proxy Address': Configure the address (FQDN or IP address).
'Transport Type': TLS
4. Configure an IP Group to represent the Skype for Business Server (see Configuring IP Groups). Make sure that you assign it with the Proxy Set that you configured in Step 3 (above).
5. Assign the IP Group of the Skype for Business Server as the destination (presence gateway) to where the device must send the PUBLISH messages: open the SIP Definitions General Settings page (Setup menu > Signaling & Media tab > SIP Definitions folder > SIP Definitions General Settings), and then in the 'Presence Publish IP Group ID' field, enter the IP Group ID of the Skype for Business Server that you configured in Step 4 (above):

6. Configure the Skype for Business LDAP server (Active Directory) to query for the Skype for Business users' SIP URIs (see Configuring LDAP Servers).
7. Configure Call Setup Rules to perform LDAP queries in the Microsoft Active Directory for the SIP URI of the caller (source) and called (destination) parties (see Configuring Call Setup Rules). The device first needs to search the AD for the caller or called number of the third-party endpoint device. For example, to search for a called mobile number, the searched LDAP Attribute would be "mobile" set to the value of the destination number (e.g., 'mobile=+' + param.call.dst.user). If the entry exists, the query searches for the Attribute (e.g., ipPhone) where the SIP URI is defined for the corresponding mobile user. If found, the query returns the Attribute's value (i.e., URI) to the device (instructed using the special 'Condition' string "presence.dst" or "presence.src"). This is the URI that the device uses as the Request-URI in the PUBLISH message that it sends to the Skype for Business Server. The configuration of the example used in this step is shown below:

Parameter

Rule 1

Rule 2

'Request Type'

LDAP

LDAP

'Request Key'

'mobile=+' + param.call.dst.user

'mobile=+' + param.call.src.user

'Attributes To Get'

ipPhone

ipPhone

'Condition'

ldap.attr.ipPhone exists

ldap.attr.ipPhone exists

'Action Subject'

presence.dst

presence.src

'Action Type'

Add

Add

'Action Value'

ldap.attr.ipPhone

ldap.attr.ipPhone

8. Configure routing rules to route the calls in the network.
9. Configure IP Groups to represent your call party entities, and assign them the group of Call Setup Rules (Set ID) that you configured in Step 7 (above). For configuring IP Groups, see Configuring IP Groups.