This Frequently Asked Questions (FAQ) document provides concise answers and practical guidance for using UCM RemoteConnect. It is intended to assist administrators and end users in understanding features, remote connectivity behavior, service limitations, and common troubleshooting scenarios.
Product Overview & Service Scope
UCM RemoteConnect (UCMRC) is a cloud-based service that enables secure remote access to Grandstream UCM6300 series IP PBXs and their extensions without requiring manual port forwarding or complex firewall configuration. It is part of GDMS (Grandstream Device Management System) which runs on Amazon AWS with 99.999% reliability and virtually unlimited scalability.
UCM RemoteConnect removes the need for exposing the UCM to the public Internet, configuring static NAT rules, or maintaining VPN tunnels. It allows remote users, Wave clients, IP phones, and SIP trunks to connect securely to a UCM deployed behind NAT or firewall devices.
UCM RemoteConnect is supported on Grandstream UCM6300 series IP PBXs. Feature availability may vary depending on the UCM model, firmware version, and subscribed RemoteConnect plan.
Yes. UCM RemoteConnect is managed through GDMS Unified Communications. GDMS is used for device onboarding, plan management, monitoring, backup operations, and remote access to UCM RemoteConnect features.
Depending on the subscribed plan, UCM RemoteConnect provides remote endpoint registration, secure SIP signaling and media relay, NAT traversal services, WebRTC access, Wave client connectivity, cloud backup integration, and call quality reporting.
No. Emergency calls placed through the UCM are not restricted by UCM RemoteConnect plan specifications. Call duration limits and concurrency limits do not apply to emergency calls.
Plans & Subscription
Yes. After a paid plan or Open Beta plan expires, the UCM RemoteConnect service is automatically downgraded to the free Basic plan. No manual action is required.
No. After the Open Beta plan expires, the UCM RemoteConnect plan will be downgraded to Basic plan automatically and the user cannot apply for the Plus plan free trial. If the UCM63xx is a new device which has no UCM RemoteConnect plan applied before, the user can apply for the Plus plan free trial for 3 months.
No. The user can only purchase 1 main UCM RemoteConnect plan for each UCM63xx and the user cannot transfer the UCM RemoteConnect plan to another UCM63xx device. If the UCM63xx device is damaged and eligible for RMA, please contact Grandstream support for help.
The UCM RemoteConnect subscription plans are sold by authorized dealers. Please contact the dealer from whom you originally purchased the UCM device to order a UCM RemoteConnect plan.
Yes. In an HA deployment, both UCM devices must have the same UCM RemoteConnect plan with HA capability. If one device’s plan expires, the HA relationship becomes invalid and service disruptions may occur.
After downgrade to the Basic plan, unsupported features such as cloud storage, WebRTC trunks, call quality reporting, alert synchronization, and custom branding are disabled. Data retention behavior varies by feature and may include delayed deletion.
Device Onboarding & GDMS Integration
Log in to GDMS Unified Communications, select the appropriate organization, navigate to UCMRC→On-Premise PBX, and click Add Device. Enter the UCM’s MAC address, serial number, and site. The device should appear online within a few seconds.
Verify that TR-069 is enabled on the UCM under System Settings→TR-069 and that the ACS URL is set to https://acs.gdms.cloud. Also ensure outbound UDP traffic on port 3478 to stun1.gdms.cloud is allowed by the firewall.
Yes, but only if the UCM device has an active paid UCM RemoteConnect plan. Devices on the Basic plan are not visible or manageable through the GDMS mobile application.
If the user wants to manage UCM6300 devices on the GDMS mobile application, the user needs to ensure that each UCM6300 device has a paid plan.
Remote access to the UCM Web UI through GDMS requires a paid UCM RemoteConnect plan. Devices downgraded to the Basic plan cannot be accessed remotely via GDMS.
Yes. GDMS supports bulk importing UCM devices using an XLS or XLSX file with the required device information. This is useful for onboarding multiple UCMs at the same time.
Endpoint Registration & Remote Connectivity
Yes. Endpoints can register to the UCM using the UCM RemoteConnect address. This allows IP phones, Wave clients, and other supported endpoints to register securely without exposing the UCM’s public IP address.
Yes. Both IP phones and Wave clients (desktop, mobile, and web) can register using the UCM RemoteConnect address. Registration and call usage are counted based on the RemoteConnect plan rules.
The following scenarios are considered as registration using UCMRC plan:
- The user’s IP phone registers to UCM63xx’s extension using the UCM RemoteConnect address.
- The user’s Wave client registers to UCM63xx’s extension using the UCM RemoteConnect address.
- On UCM63xx trunk configurations (for register trunk), the UCM RemoteConnect address of the register UCM63xx is used. All trunks are counted into registered users if there are multiple register trunks configured this way,
If the same UCM63xx’s extension is registered on multiple endpoints including Wave app/IP phones/SIP trunks using the UCM RemoteConnect address, each endpoint is counted as a remote registered user. For example, if the same extension is registered on Wave Android app and Wave PC, they are counted as 2 registered users.
In UCMRC plan, the number of remote calls is calculated using the following method:
- The caller and callee lines are counted separately when using UCMRC remote server address in both clients.
- As long as the caller or callee party uses UCMRC remote server address, the call is counted as a remote call and caller/callee are counted separately.
- Trunk is also counted as a caller or callee party. Each call party via the trunk is counted as one remote call separately.
Please see below table for illustration of examples.
Assuming UCM X and UCM Y have SIP trunk configured using UCM’s local address, UCM X and UCM Z have SIP trunk configured using UCM RemoteConnect address. When a call is established between user A and user B, the number of remote calls in each UCM will be counted as follows:
If multiple users make multiple calls on the same trunk, all calls will be counted towards the number of remote calls.
User A | User B | Remote calls on UCM X | Remote calls on UCM Y | Remote calls on UCM Z |
Register to UCM X using RemoteConnect address | Register to UCM X using RemoteConnect address | 2 | / | / |
Register to UCM X using RemoteConnect address | Register to UCM X using local address | 1 | / | / |
Register to UCM X using local address | Register to UCM X using local address | 0 | / | / |
Register to UCM X using RemoteConnect address | Register to UCM Y using local address | 1 | 0 | / |
Register to UCM X using RemoteConnect address | Register to UCM Y using RemoteConnect address | 1 | 1 | / |
Register to UCM X using local address | Register to UCM Y using local address | 0 | 0 | / |
Register to UCM X using local address | Register to UCM Y using RemoteConnect address | 0 | 1 | / |
Register to UCM X using RemoteConnect address | Register to UCM Z using local address | 2 | / | 1 |
Register to UCM X using RemoteConnect address | Register to UCM Z using RemoteConnect address | 2 | / | 2 |
Register to UCM X using local address | Register to UCM Z using local address | 1 | / | 1 |
Register to UCM X using local address | Register to UCM Z using RemoteConnect address | 1 | / | 2 |
“RemoteConnect Sessions” indicates the number of currently active calls that are using the UCM RemoteConnect service.
After the paid UCMRC plan expires, if the Wave client uses the UCM63xx’s public IP address as SIP server, the login operation will not be counted as remote registration. However, if the user makes a call on Wave, the call will be counted as a remote session unless the UCM admin disables the option “Media NAT Traversal Service” on UCM630x Web UI→RemoteConnect→Plan Settings.
If you prefer the calls not counted as RemoteConnect sessions by the UCMRC plan, please disable the option “Media NAT Traversal Service” on UCM web UI. After the option is disabled, the UCM admin needs to ensure that STUN server and TURN server have been configured in the UCM63xx device so that calls can be established successfully.
For more configuration details, please refer to UCM6300 Remote Work Environment – Setup Guide.
No. No matter whether the UCM option “Media NAT Traversal Service” is enabled or not, the registration and calls on IP phones will not be considered as using UCM RemoteConnect service even though the phone is using the UCM’s public IP address as the SIP server.
However, the user may encounter media NAT traversal issues and audio may be blocked. To resolve this issue, the user can configure STUN/TURN server on the IP phone. Please note if the STUN/TURN server addresses are provided by UCM RemoteConnect service, the call on the non-Wave endpoints will still be counted as a remote session.
SIP Accounts & Synchronization
Yes, if the UCM has an active UCM RemoteConnect plan that supports SIP extension synchronization and the option SIP Extension Sync is enabled on the UCM Web UI. Extensions created on the UCM will then be synchronized to GDMS.
The SIP Extension Sync option is disabled when the UCM RemoteConnect plan is the Basic plan. To enable SIP extension synchronization, the UCM must be upgraded to an Open Beta or paid RemoteConnect plan.
After plan expiration, previously synchronized SIP extensions remain visible in GDMS. However, newly created extensions on the UCM will no longer be synchronized unless SIP Extension Sync is re-enabled with a supported plan.
If the disabled extension was synced to the GDMS platform previously, it will be removed from the GDMS platform after it is disabled on the Web UI of the UCM6300 series device.
No. SIP extensions are managed on the UCM itself. GDMS only reflects synchronized data and cannot create, delete, or modify SIP extensions directly.
Calling, Meetings & Wave Clients
On the Basic UCM RemoteConnect plan, remote calls are subject to a maximum call duration. When this limit is reached, the call is automatically terminated.
No. WebRTC trunk functionality is not supported on the Basic plan. After plan expiration, the WebRTC trunk URL will no longer be accessible.
No. Wave CRM and third-party add-ins are supported only on Business and Enterprise plans. After plan expiration, these integrations are disabled.
Yes. UCM RemoteConnect allows users to join voice and video meetings remotely using Wave clients or supported browsers, depending on the subscribed plan.
No. Emergency calls are not subject to UCM RemoteConnect plan limitations, including call duration and concurrency limits.
Calling & Telephony Features
UCM RemoteConnect supports standard UCM telephony features including inbound and outbound calls, call hold, blind and attended transfer, call park, voicemail, ring groups, and call queues, subject to UCM configuration and endpoint capability.
Yes. Remote users registered through UCM RemoteConnect use the same extensions, dialing rules, and call routing logic as local users.
Yes. Call hold, blind transfer, attended transfer, and call park are supported for remote users when using compatible endpoints or Wave clients.
Yes. Video calls and video meetings are supported via Wave clients and compatible Grandstream endpoints, depending on endpoint capability and UCM configuration.
Yes. Paging and intercom features work for remote endpoints registered via UCM RemoteConnect, provided the endpoint model supports these functions.
Yes. Remote users can participate in call queues and ring groups as long as they remain registered to the UCM.
Network & Security
UCM RemoteConnect provides built-in NAT traversal by routing SIP signaling and media through Grandstream cloud services. This eliminates the need for manual port forwarding or public IP exposure on the UCM.
The UCM must be able to establish outbound connections to GDMS and UCM RemoteConnect servers. This includes UDP port 3478 for STUN connectivity and TLS-based SIP and management traffic as required by the service.
When Media NAT Traversal Service is enabled, media streams may be relayed through the UCM RemoteConnect service to ensure reliable audio and video. If disabled, administrators must configure STUN and TURN servers manually.
Yes. UCM RemoteConnect uses TLS for SIP signaling to provide secure communication between endpoints, the UCM, and the RemoteConnect service.
Yes. GDMS supports IP address access rules that allow administrators to restrict login access by IP address or subnet for enhanced security.