I am not sure I understand what you are asking. If you are asking how are VoIP packets sent to a polycom phone, well it depends on the phone.
In the case of the soundpoint 300, this is an IP phone already, so you need to subscribe to a service that provides you VoIP services to your soundpoint, or you need to setup a VoIP system to send & receive your calls.
I want to create a Voip Soft phone.
on the PC.I.e When a customer speaks to the agent. The agent must be able to record the voice of the customer.
The system used is a Polycom soundpoint 300.Polycom supports VOIP.A cable plug in to the Ethernet Card from the phone.