A combo router combines a modem and router on one device. Some Internet Service Providers (ISPs) give their customers combo routers instead of stand-alone devices. While combo routers can be sufficient for small setups, they can lack the features and functionality that may be required for 8x8's VoIP services to work reliably. The causes for common issues with combo routers vary depending on the model, but they usually result from enabled SIP-ALG, firewall protection, SPI, or NAT.
Common combo router call quality issues that may need firewall or router settings to be changed include:
- The inability to make or receive calls
- Phones going offline
- One-way audio
Most combo routers come with SIP-ALG enabled by default, a Network Utility Test can often identify if the SIP-ALG is enabled, however, the results aren't always accurate. If the root cause is the SPI or firewall, then lowering the firewall settings can usually fix the problem—although, this is often only a short-term solution.
When 8x8 users with combo routers receive troubleshooting from their ISP, this can result in configuration issues with 8x8 services since the modem and router configuration are controlled by the ISP. Any router settings configured for 8x8 services need to be checked and possibly reset if you receive troubleshooting from your ISP.
We prefer our customers to have stand-alone modems and routers but this is not a requirement. We assume that if the router provides the customer with Internet service, it ought to work with our services as well.
For information on configuring routers, see Configuring Your Network for 8x8 service.