This is a service that I have been waiting for some time to become open to the public; Skype for SIP.

This benefits of this service allow for:

1. Skype users to call your UC500 using your Skype username
2. Allow UC500 users to make outbound calls to Skype or PSTN users using the Skype SIP trunk
3. Allow inbound PSTN calls over the Skype SIP trunk when there is a phone number assocviated with the Skype SIP trunk.

This article will outline the configuration steps.

1. First you must setup a Skype for SIP account. Once you have completed that, you will see you SIP account details in your Skype business control panel.
2. WAN QoS Configuration - Next, open up CCA Version 2.2 and navigate to the Internet Connection section, select the interface and click Modify, then click on Traffic Shaping tab to configure QoS settings for the WAN connection. On the Traffic Shaping tab, check Enable Traffic Shaping, enter the appropriate upstream bandwidth for your WAN connection in Kbps and reserve the appropriate bandwidth for
   Skype for SIP calls over the WAN.
3. Configuring Firewall on the UC500 - Navigate to Firewall and DMZ. The Firewall settings can be set via CCA to either HIGH, MEDIUM or LOW levels based on the desired customer requirement. Please ensure the firewall is always enabled – if the UC500 is not the firewall device in
   the network, you can disable the firewall but be sure to have the appropriate restrictions on your upstream firewall device to restrict traffic to the UC500.
4. Configure SIP Trunking - Navigate to SIP Trunk. On the Service Provider drop down, scroll down to Skype to SIP and select Add.The SIP Trunk service provider drop down will have Skype for SIP an option. Select thatand enter various fields based on your SIP trunk account as below:
   
   • Proxy Server (primary): sip.skype.com (Skype for SIP address)
   • Registrar Server: sip.skype.com (same as above)
   • Digest Authentication: Enter SIP User & password from Skype for SIP account
   • SIP Domain name: any valid domain name for the system
   • User Credentials: Click Add and enter SIP User & password from Skype for SIP account
   • Click “OK” when complete.
   
5. CCA will prompt to enter a main trunk number - enter the SIP Username as the main trunk number for now & check the box to add Skype for SIP to the outgoing dialplan, then hit OK.
6. Inbound Dialplan Configuration - After the voice configuration is saved, navigate to Configure > Telephony > Dial Plan > Incoming and select the Direct Dialing tab. This has two sections:
   
   Direct Dial to Internal Extensions – which is direct mapping between external PSTN number and internal extension
   
   In the “Direct Dialing to Internal User Extensions” section, click on Add. In the dialog box, enter below:
   Enter a Description such as DID-SIP
   Enter DID range start / end as the Skype for SIP numbers (9905…….)
   Pick Internal Extension Start / End Numbers which are the internal extensions
   on the system
   Click OK
   Additional DIDs if purchased from Skype can be added and mapped to internal extensions as required.
   
   Direct Dial to Auto Attendant, Groups, Operator – which is mapping one or more external PSTN numbers to a single internal extension (eg. operator) In the “Direct Dialing to Auto Attendant, Groups, Operator” section, click on Add. In the dialog box, enter below:
   Enter a Description such as AA-SIP Enter DID range start / end as the Skype for SIP number Pick Internal Number Extension Type as Auto attendant Click OK
7. Outgoing Dialplan - Navigate to Configure > Telephony > Dial Plan > Outgoing and setup the appropriate preferences for outbound dialing. As Skype for SIP does not support emergency numbers it is recommended to change the Trunk Priority to PSTN only for emergency calls. Similar configuration would apply to any dial patterns that you do not want to route over the Skype for SIP network. Also, it may make sense to chance the access code for calls over Skype for SIP to use 8 instead of 9.
   
   Once done – click “OK” at the bottom.
8. Outbound Caller ID - Make sure the Caller ID on Telephony > Dial Plan > Outgoing > Caller ID tab is setup to Use Main PSTN number under the Caller ID option field. Using any other option is not supported at this time.
9. Save Configuration - Click on the “Save” button on the CCA top bar to save the configuration on the UC500: This completes the CCA configuration for Skype for SIP Trunking.