How do you set up the polycom ip 6000 with sip connection to Iwatsu ECS system

You'll need a SIP device license for the ECS, a virtual card and port for the device configured, assign an extension number, use that extension number as the user on the SIP phone, use the LAN 2 address for the proxies and registrar. You may have to change the Transport setting away from Polycom default to UDP.