A Three Star designation indicates that the device has undergone all of the Two Star and One Star tests as well as a full Physical and Environmental (P&E) evaluation. Such full P&E testing indicates that all P&E tests were performed and that these tests were overseen in person. This is the highest and most thorough level of testing available
This level of testing demonstrates the device functionality on the network – it works. If the device fails to function (at the home or office), it is not a reflection of the modem, but it's in direct relationship with the quality of line and signal strength going into the office/home. DOCSIS 3.0 requires a higher frequency level. Poor line quality will impact the signal strength and cause a failure for the device to sync with the network. Modulation and demodulation functions (MODEM) defaults the attempt to negotiate speeds at the fastest level, upon failure to negotiate a current speed results in the negotiation dropping to the next available rate, repeating the process until a speed is negotiated. DOCSIS 3.0 does operate with a minimum frequency requirement. Once failure to negotiate at the minimum occurs the next subsequent step is change out the protocol and drop to DOCSIS 2.0. Due to a substantial amount of old lines in the MAN, Comcast will be forced to continue supporting DOCSIS 2.0 until the physical network upgrade reaches substantial completion. The real question is; does substantial completion reflect the last mile of physical line entering the premises? My point is there are a lot of homes and offices with aged lines entering the house. Who is responsible for the upgrade of the cable?