The voice services come pre-configured on Huwaei hg8245q, all you need to do is switch it on from the Internet interface of your router. I will discuss the steps involved in the process below.
Default username is: !!Huawei
Default password is: @HuaweiHgw
Local Port: 5060
Use outbound: un-ticked
User secondary server: un-ticked
Save the settings