Remote extensions and remote offices The remote extension feature gives PBX users the freedom to attend to office calls irrespective of their geographic location. It enables remote access to the enterprise's PBX/IP PBX regardless of employee's whereabouts or telephony device (IP phone, WiFi phone, Smartphone, laptop, or any other VoIP devices). Remote office feature allows enterprise users to integrate two or more CooVox IPPBX systems located in different locations together as one integrated IP phone system. Phone calls amount those offices are totally free of charge. Users also can utilize the trunk lines on the other office site to make outbound phone calls. If you found remote office feature is an excellent solution for your multi-site offices, but you have more than 3 or even more offices to be integrated please consider deploying the CTMS solution. Copyright 2016 ZYCOO. All Rights Reserved.
Contents Remote extensions...1 Remote SIP extensions...1 Remote IAX extensions...2 Remote Web Extensions...3 Remote extensions via VPN...4 Remote Offices...5 Remote office over SIP trunks...5 Remote office over IAX trunk...7 Inter-branch phone calls...9 Remote office via VPN... 10 Copyright 2016 ZYCOO. All Rights Reserved.
Remote extensions Remote SIP extensions To register remote SIP extensions please follow the steps below: Step 1: Port forwarding A remote SIP extension requires the IPPBX system s SIP signaling port 5060 and RTP port range 10001-10500 to be opened to the Internet. So the SIP endpoints can register to the IPPBX system and make phone calls. Step 2: NAT support To help VoIP traffic passing through NAT, you have to configure NAT support on the CooVox IPPBX system. Navigate to Web menu Advanced->Options->SIP Settings. In the NAT Support section specify your public IP and local network addresses. Specifications: External IP/External Host: Here in these 2 blanks you should give your public IP address. If you don t have a fixed public IP you can use the DDNS feature on the CooVox IPPBX system, after DDNS is successfully configured then you give your DDNS domain name here. External TCP Port/External TLS Port: If you are going to run SIP over TCP or TLS for remote extensions, you should enable TCP or TLS support in the General section upper on this page, and port forwarding on the router/firewall should be with TCP protocol. The port number here you have to specify is the external port number you defined on the router/firewall. External Refresh (sec): The refresh interval of the External Host Local Network Address: Your local network address/addresses. Step 3: Register remote extensions Here we take Coofone D60 for example: 1
Almost the same as you register a local extension, but in the server address blank you should use public IP or the DDNS domain name instead of private IP address. If it runs on TCP or TLS, please click Advanced SIP Settings and choose TCP or TLS in the Transport Protocol dropdown list. Notice: SIP extension over TCP/TLS protocol also needs to enable TCP/TLS for the extension. Please select the transmission protocol on the extension configure page before registering from the phone. And also NAT needs to be enabled. Remote IAX extensions IAX carries both signaling and media on a unique port 4569. The advantage of IAX is it has good NAT traversal than SIP. So if you want to register a remote IAX extension, all you have to do is open port 4569 on the router for the IPPBX system. NAT support is not needed to be configured. First you have to create IAX extension/extensions. Navigate to Web menu Basic->Extensions page, click New User button to create an IAX extension. You can register IAX extensions on both Zycoo Coofone D30 and D60. 2
Notice: IAX only works on UDP transmission. So when you are doing port forwarding on your router/firewall please apply UDP only. Remote Web Extensions Web extension (WebRTC) feature doesn t require any IP phones or softphones, it utilizes only a Web browser even without any plugins to register to your CooVox V2 IPPBX system as an extension. Step 1: Upgrade WebRTC patch The WebRTC patch upgrading will build the JS WebRTC GUI into CooVox V2 system. Please download it from here. Step 2: Port Forwarding WebRTC carries both signaling and media on port 8089, CooVox IPPBX Web interface works on port 9999. So you have to open these 2 ports on your router/firewall. Step 3: Create Web Extension Navigate to Web menu Advanced->Web Extensions page. Click New User to create a Web Extension number. 3
Step 4: Access the JS WebRTC GUI and register Web extension With the URL https://117.176.159.157:9999/webrtc you can access the WebRTC GUI to register remote web extensions as below. For more details about Web extensions please click here. Remote extensions via VPN The above approaches of implementing remote extensions will expose your IPPBX system to the Internet which may incur your IP phone system become a target of the malicious users and hackers. So it is recommended you do remote extensions over VPN connections. With VPN connections you only have to open the VPN service port on the VPN server side, SIP port, RTP ports, IAX port and NAT support are all not needed. Please refer to the CooVox V2 user manualin chapter 5.3 to setup VPN connections between your CooVox V2 IPPBX system and the endpoints then register remote extensions over the encrypted VPN tunnels. An example of remote SIP extension over PPTP VPN as below: 4
You have setup PPTP VPN server on the CooVox V2 IPPBX system. The server VPN IP address is 172.168.0.1. And you can connect your iphone via PPTP VPN to the VPN server (CooVox V2 IPPBX). Then you need to register the extension using server IP 172.168.0.1. Remote Offices You can utilize SIP or IAX trunk to integrate 2 or more CooVox IPPBX systems together on the remote office sites. Once they have been integrated the inter-branch phone calls are totally free of charge. First of all, make sure at least one of the offices has a fixed public IP address. If not, you have to configure DDNS first. In the following examples, we call the office with public IP address office A, the other one we call it office B. Please follow the steps below to do the integration. Notice: Before integrating the IPPBX systems, please make sure they use different extension ranges. For this integration if there are same extension numbers on both sides the inter-branch phones will fail. Remote office over SIP trunks Step 1: Port forwarding and NAT support for office A IPPBX system It s the same as you register remote extensions you have to open SIP signaling port 5060 and RTP port 10001-10500 on your router/firewall for the IPPBX system. NAT support is also required for remote office integration, please refer to the instructions of remote extensions Step 2. 5
Step 2: Create A SIP peer trunk on office A IPPBX system Navigate to office A IPPBX Web menu Basic->Trunks->VoIP Trunks page, click on New VoIP Trunk to create a peer trunk. This trunk will be used for the other IPPBX to connect. You have to give this trunk a name and tick Peer Mode then define a username and password. NAT also needs to be enabled. And click Save and the trunk is ready. Step 3: Create a dial rule for office A IPPBX System Navigate to office A IPPBX Web menu Basic->Outbound Routes->DialRules page. Click New DialRule to add a new dial rule. 6
This dial rule is dedicated to call office B, please make sure the dial pattern is different from other dial rules within this IPPBX system. The above example means the extension users from office A dial the number with prefix 5, the call will go through peer trunk OfficeA. Before the call is finally sent the prefix will be removed. After this new dial rule is created remember to enable it in the dial plan. Step 4: Create a SIP VoIP trunk on office B IPPBX system Navigate to office B IPPBX Web menu Basic->Trunks->VoIP Trunks page. Click on New VoIP trunk to add a new VoIP trunk. This trunk will be used to connect to office A. Give it a name and in the Host blank fill in the public IP or domain of office A. Credentials are what you have defined on the office A IPPBX system. Step 5: Create a dial rule for office B IPPBX system Navigate to office B IPPBX Web menu Basic->Outbound Routes->DialRule page. Click New DialRule to add a new dial rule. Please refer to Step 3. After the dial rule is created don t forget to enable it in the dial plan. Remote office over IAX trunk Step 1: Port forwarding for office A IPPBX system IAX runs both signaling and media on a single port 4569. So you just have to open this port on your router/firewall for remote office IAX trunk integration. Step 2: Create an IAX peer trunk on office A IPPBX system Navigate to office A IPPBX Web menu Basic->Trunks->VoIP Trunks page. Click New VoIP Trunk to add a new VoIP trunk. 7
Give this trunk a name, select IAX in the Protocol dropdown list, tick Peer Mode, and define a username and password. This trunk will be used for office B IPPBX system to connect. Step 3: Create a dial rule for office A IPPBX system Navigate to office A IPPBX Web menu Basic->Outbound Routes->DialRule page. Click New DialRule to add a new dial rule. With this dial rule the extension users from office A will be able to call office B extension users using a prefix 5. After the rule is created remember to enable it in the dial plan. Step 4:Create an IAX VoIP trunk on office B IPPBX system 8
Navigate to office B IPPBX Web menu Basic->Trunks->VoIP Trunks page. Click New VoIP Trunk to add a new trunk. This trunk will be used to connect to office A. In the Protocol dropdown list select IAX, in Host blank fill in the public IP or domain of office A, and the credentials are what you have defined office A IPPBX system. Step 5: Create a dial rule for office B IPPBX system Navigate to office B IPPBX Web menu Basic->Outbound Routes->DialRule page. Click New DialRule to add a new dial rule. Please refer to Step 3. After the dial rule is created don t forget to enable it in the dial plan. Inter-branch phone calls With the remote office integration you can make inter-branch extension calls and inter-branch outbound calls. For inter-branch extension calls, it is as easy as dialing local extensions, just one more prefix needs to be dialed in front of the other office s extension number, and then the call can go through. About inter-branch outbound calls, it means you can dial external phone numbers from local office via the IPPBX system of the remote office site. Before it works, one more configuration needs to be done. Navigate to Basic->Trunks->VoIP Trunk page. Edit the trunk (SIP or IAX) properties, in the Advanced section choose a dial plan in the Context dropdown list. When done you are able to dial from one office to the other side and use the trunk lines of the other office to place an outbound calls. It will only charge at a local city 9
phone call rate. The dialing principle is prefix+prefix+number. For example, office A calls office B with a prefix 5, and office B calls outbound with a prefix 9, the number in B city is 1234567, so extension user of office A dials 591234567 to make the call. Remote office via VPN The above mentioned approaches of integrating remote offices with SIP/IAX trunks will expose your IPPBX system to the Internet which may result in your IP phone system becoming a target of the malicious users and hackers. It s the same as remote extensions, so establishing a secured VPN connection between the IPPBX systems first, then build the trunks over the VPN connection is recommended. Please refer to the CooVox V2 user manual in chapter 5.3 to setup VPN connections between the remote offices, and then establish the SIP/IAX trunk connection. All the trunk settings are the same as instructed previously, only in the remote office IPPBX system you have to use the VPN server IP instead of public IP or domain name. 10