Problems relating to SIP-ALG:
U-Verse service requires customers to use a router that was designed specifically for U-Verse Internet, TV, and phone service. This can sometimes cause problems because the router has a default setting called SIP-ALG that cannot be disabled and the router cannot be replaced while using U-Verse Internet. SIP-ALG is a router function that will cause Nextiva’s traffic to be rewritten, which can cause problems such as one-way audio, dropped calls, and inbound and outbound call failure.
Nextiva is proactively prepared for this. Our server will send traffic that avoids this disruptive SIP-ALG functionality, but the phones/devices connected to this network may need to be modified, as well.
If you are familiar with making changes to your voice over IP phone/device, you will want to modify the source port of the phone to a port other than 5060 and reboot the U-Verse router. If you are not familiar with making this change, we encourage you to contact our support at 800-285-7995 and request assistance.
Inability to use Quality of Service (Bandwidth Allocation):
Quality of Service (QoS) is a function within some routers that allows you to allocate bandwidth to specific devices as needed. Since U-Verse requires the use of their routers, you are incapable of implementing a QoS capable router while using U-Verse Internet service. If you are using U-Verse Internet, you will be required to monitor the bandwidth being used at the location. If there is too much downloading/uploading on the network it could cause the phone quality to degrade.