After deploying a new AI-powered system to boost downstream performance on the cable access network last year, Comcast fast-tracked a version of it focused on the upstream amid a pandemic that caused a spike in usage as consumers hunkered down at home.
That platform, called Octave, enables Comcast to rapidly pinpoint network anomalies and noise-fueled issues by polling and analyzing anonymized data from gateways and modems. In addition to utilizing that data to locate and fix network impairments, Comcast is likewise using it to help boost the efficiency and performance of the access network.
Regarding access network efficiency, Octave is enabling Comcast to dynamically set the maximum allowed modulation profiles of individual cable modems rather than being required to drop all of the modems to a profile that represents the lowest common denominator that can be supported by all of the modems on the access network.
The feedback from Octave, for example, helps to ensure that modems or gateways that are capable of humming along at 4096-QAM can utilize that higher and more data-efficient modulation profile even if another modem in the group has to dip down to, say, 256-QAM because of LTE interference or some other type of network impairment that can cause noise to bleed back into the HFC network.
To enable this in real time with Octave, Comcast feeds anonymous polling data from tens of millions of devices on its access network to an AI decision engine. This engine analyzes the information and then sends commands to the cable modem termination system to dynamically set the highest supported modulation profiles of individual modems on the network.
"We want to be able to optimize the delivery, based on the actual edge reality," explained Elad Nafshi, SVP of next generation access networks at Comcast. "Now I can open up a whole bunch more capacity that is optimized by the time of day and optimized to the customer that I can act on in real-time and ... fluctuate that delivery to ensure [customers] are getting the maximum efficiency down to the house."
Tony Werner, Comcast's president of technology, product and Xperience, told Fast Company that a version of Octave deployed prior to the pandemic increased download capacity across its network by 36%. When the pandemic hit, Comcast then accelerated the development and rollout of a version of Octave tailored to the upstream. That resulted in a 20% increase in upstream capacity, the report said.
Nafshi said Octave has helped Comcast manage and optimize the four carriers it is using for the spectrum being applied to its DOCSIS 3.0-based upstream. (Comcast has not yet launched OFDMA-based DOCSIS 3.1 upstream channels.) But the AI-powered technology has also set Comcast down the path of eventually adding a fifth and possible sixth channel in the lower part of the spectrum in the 5MHz-42MHz range that's being allocated for the upstream.
"Not only are we making better use of the four upstream we had before, we're able to add additional upstream channels and, therefore, add additional upstream capacity," Nafshi said.
For more about Comcast network initiatives undertaken during the pandemic, including the acceleration of capacity upgrades on its core and regional networks, please see this story at Light Reading: Comcast beefs up network capacity, uses AI to keep data demands in check.
— Jeff Baumgartner, Senior Editor, Light Reading, special to Broadband World News