This is a step-by-step guide to implement a Skype for Business Cloud Connector Edition Server which directly connects to an Internet SIP Trunk Provider without the need of an on-premise PSTN Gateway device.

Skype for Business Cloud Connector Edition Topology and port requirements

Skype for Business Cloud Connector network layout / topology

Note: The ports between the Internet SIP Trunk Provider and your Mediation Server may vary depending on the Provider you use. The ports mentioned in the picture are valid for Netstream AG (Switzerland).

Hardware requirements

https://technet.microsoft.com/en-us/library/mt605227.aspx#BKMK_Requirements

Certificate requirements

The certificate must contain the Edge Server Public FQDN as common Name. For each SIP Domain there must be an entry sip.domain.ch.

Example

CN=accessedge.ptschumi.ch

DNS Name = accessedge.ptschumi.ch DNS Name = sip.ptschumi.ch DNS Name = sip.philippetschumi.ch

DNS requirements

Cloud Connector

DNS RecordPublic IP
accessedge.domain.comEdge Server Public IP
media.domain.comEdge Server Public IP

Skype for Business Online

For each SIP Domain:

TypeHostDestinationTTL
SRVsip.domain.comsipdir.online.lync.com1h
SRVlyncdiscover.domain.comwebdir.online.lync.com1h
TypeServiceProtocolPortWeightPriorityTTLHostDestination
SRV_sip_tls44311001hdomain.comsipdir.online.lync.com
SRV_sipfederationtls_tcp506111001hdomain.comsipfed.online.lync.com

Installation

Enable Hyper-V

According the prerequisites you need to install the Skype for Business Cloud Connector VMs on a dedicated hardware with Windows Server 2012 R2 Datacenter Edition (English).

You then need to enable the Hyper-V role.

Enable-WindowsOptionalFeature -Online -FeatureName Microsoft-Hyper-V -All

Note: The installation on a Windows Server 2016 – even it’s not supported yet – works fine too.

Network Adapters on Hyper-V 

Create the following Virtual Switches in Hyper-V Manager:

Physical NICVirtual SwitchNetwork
NIC1SfbCCEManagementInternal Network
NIC2SfbCCEInternalExternal Network (Coorporate Network)
NIC3SfbCCEPublicExternal Network (DMZ Private)
NIC4SfbCCESIPTrunkExternal Network (DMZ Public / Public IP)

Pre-installation

  1. Verify that .NET Framework 4.6.1 or later is installed
  2. Download Source: https://aka.ms/CloudConnectorInstaller and install
  3. Open PowerShel
  4. Import Skype for Business Cloud Connector Module
    Import-Module CloudConnector
  5. Adjust Cloud Connector Directories to your needs
    Set-CcSiteDirectory "D:\CloudConnector\SiteRoot\"
    Set-CcApplianceDirectory "D:\CloudConnector\ApplianceRoot\"
  6. Set the path for the external Edge certificate
    Set-CcExternalCertificateFilePath -Path "D:\Sources\edge.pfx" -Target EdgeServer
  7. Set the path for the SIP Trunk certificate (optional, necessary when using encryption)
    Set-CcExternalCertificateFilePath -Path "D:\Sources\mediation.pfx" -Target MediationServer
  8. Create CloudConnector.ini sample file
    Export-CcConfigurationSampleFile

Define parameters in CloudConnector.ini 

In the CloudConnector.ini file you need to set the necessary parameters. For an explanation of CloudConnector.ini parameters and example file visit this blog post. You can copy the previously created sample file and rename it to CloudConnector.ini.

Main Installation

  1. Change the excecution policy if restricted
    Set-ExecutionPolicy RemoteSigned
  2. Download the binaries
    Start-CcDownload
  3. Create Base VM Image
    Convert-CcIsoToVhdx -IsoFilePath "D:\Sources\Windows2012R2.iso"
  4. Register the appliance with Office 365
    Register-CcAppliance
  5. Start the installation
    Install-CcAppliance

Additional configuration for internet SIP Trunk

If you configure an Internet SIP Trunk the only supported scenario is to have two network adapters where one has assigned a public IP for the connection to the SIP Trunk Provider.

To get this done, follow these steps:

  1. Connect one Hyper-V network interface to public DMZ/IP Zone.
  2. Create another Virtual Switch in Hyper-V Manager. In my case I called it SfbCCESIPTrunk.
  3. Modify the Settings of your Mediation Server VM and add a new Virtual Network Adapter
  4. Connect it to the previously created Virtual Switch (SfbCCESIPTrunk)
  5. Sign-in to the Mediation Server VM
  6. Configure the newly added network Adapter with your public IP (fill in only IP and subnet mask)
  7. Configure a static route for your SIP trunk:
    route -p ADD 'SIP Provider IP' MASK 255.255.255.255 'Default Gateway IP'

In some cases you need to configure some more parameters on the SIP Trunk as requested by the SIP provider:

  1. Add the Domain Administrator to the CsAdministrator Group in Active Directory.
  2. Edit the Parameters of the trunk if necessary with
    Set-CsTrunkConfiguration

Office 365 configuration

  1. Download and install Skype for Business Online PowerShell Module: https://www.microsoft.com/en-us/download/details.aspx?id=39366
  2. Connect to Skype for Business Online:
    Set-ExecutionPolicy RemoteSigned
    Import-Module SkypeOnlineConnector
    $credential = Get-Credential
    $sfboSession = New-CsOnlineSession -Credential $credential
    Import-PSSession $sfboSession
  3. Set up Hybrid connectivity:
    Set-CsTenantHybridConfiguration -PeerDestination 'External Access Edge FQDN' -UseOnPremDialPlan $false
    Set-CsTenantFederationConfiguration -SharedSipAddressSpace $True

Enable users

To assign a phone number to a user, you must first assign a Skype for Business and a Phone System license to the user.

Set-CsUser -Identity "username" -EnterpriseVoiceEnabled $true -HostedVoiceMail $true -OnPremLineURI "tel:+phonenumber"

Start your call

You’re done now with your initial Skype for Business Cloud Connector setup. Now you can sign-in with a user and call in/out through PSTN with using your internet SIP Trunk Provider.