What’s causing the issue?
The Softphone sends out information to the RingCentral servers, and processed information is sent. The port numbers 5060-5090 which is standard for VOIP acts as a gateway for the Softphone to send and receive data while the port numbers 8000-8200 is the gateway to send and receive voice signals. In any case that one of these ports are not allowed within the home or office network, such issues will occur.
How to resolve the issue?
A method called port forwarding or port triggering on the routers assures that a specific port is ready to listen to all types of information that is sent and receive over the network.
A type of port forwarding where outbound traffic on predetermined ports sends inbound traffic to specific incoming ports. Port triggering "triggers" an open incoming port when a client on the local network makes an outgoing connection to a predetermined port on a server.
Port Triggering is more secure than port forwarding, because the incoming ports are not open all the time, they are open only when a program is actively using the trigger port. One major advantage of port triggering is that it allows computers behind a NAT-enabled router to provide services which would normally require a static host (one with an unchanging network address).
What is NAT?
Network Address Translation or NAT serves as a middle man between a local network or the Internet. This creates a single IP address to represent your network in the public domain (or the Internet).
The disadvantage of port forwarding is that it only allows one client on the network to use a particular service that occupies a particular port.
How to enable port forwarding/port triggering?
How to set up port forwarding on a Linksys router
How to set up port forwarding for D-Link routers
How to set up port forwarding on a Netgear router
How to set up port triggering on a Linksys router