C Quality of Service and Firewall¶
The router is able to provide extra services like Firewall and QoS.
In our case we didn't changed definitively the configuration of the firewall or the NAT (only for learning and testing purposes) but we have set some QoS to the VoIP traffic.
There are mainly two simple ways to provide QoS in our system: Marking our traffic from the Ethernet interfaces used by the Asterisk server and the IP-DECT, or in a more elegant way, marking the VoIP traffic (UDP 5060 for signaling and UDP 10000 to 20000 for voice data). Once the packets are marked, we can set a rule to prioritize this traffic.
The automatic algorithms of the routerOs that can improve the performance and reliability of SIP are enabled, like SIP/ALG. We have provided as well the VoIP traffic with a minimum bandwidth. In our system case only one call can be established to the Internet (we had configured just one SIP account). We should consider an increase of the bandwidth if necessary, for example with the setup of a SIP trunk or several SIP accounts.
Other aspects may be optimized in the configuration of the mikrotik router, such as jitter buffering.