“The question is: can we scale to gigabit speeds? And the answer is: yes, unequivocally,” said CableLabs CTO Ralph Brown, as he presided over a demonstration of multiple-gigabits per second (Gbps) delivery using DOCSIS 3.0 and even faster rates with a prototype version of DOCSIS 3.1, with both demos performed with DOCSIS chips supplied by Broadcom.
In the 3.0 demo, CableLabs was bonding 128 channels (using four 32-channel cable modems) to crank out in excess of 4 Gbps in a total of 768 MHz. Gigabits, unequivocally, yes.
The 3.1 specification is far from done, but it is certain the spec will include OFDM modulation and LDPC error correction. So in a demo that relied on those two technologies, CableLabs was pushing data at a clip in excess of 6 Gbps, but in only 650 MHz, the better to show the spectral efficiency inherent in the move to OFDM.
Given what they’ve achieved so far, Brown said, “We think you can do 10 Gbps over 1.2 GHz.”
Bonus? MSOs should be able to easily drop DOCSIS 3.1 into their networks, with little or no tweaking of the network.
In this demonstration, next-generation cable transport – including DOCSIS 3.1 and EPoC (EPON Protocol over Coax) – will utilize technologies from Broadcom to encode digital data across multiple frequencies using OFDM (Orthogonal Frequency-Division Multiplexing) and LDPC (Low-Density Parity-Check) error correcting codes to maximize network capacity.
In another demo, CableLabs was streaming error-free 4K Ultra HD video over HFC, using the newest OFDM technology. The pictures looked spectacular.