Abstract: A Packet Processor for a communication apparatus, for processing received and transmitted data streams made of packets. Each packet includes a header and a payload section, which includes a receiving part, a transmitting part, a Backbone Bus for conveying management data, instructions and addresses between various components of the Packet Processor, and a timing and control unit for administering the operation of the Packet Processor, and for timing of using transmission slots for the transmit path. The receiving part includes a receiving PHY interface by which a flow of data stream is conveyed from a Modulator-Demodulator section of the modem to the Packet Processor. The receiving part further includes a receiving Tubular Bus which received the flow of data stream, conveyed from the modem to the Packet Processor, the receiving Tubular Bus conveys data, while processed, the direction from the receiving PHY interface to a host interface.