Getting the Most out of Your DOCSIS 3.0 Network: Dynamic Load Balancing of Bonded Modems

We’re using more bandwidth than ever. And that amount is growing by...

Jeff Walker

Jeff Walker-Sr. Director, CMTS Product Marketing, ARRIS

We’re using more bandwidth than ever. And that amount is growing by nearly 50 percent per year.

The reason is that we’re streaming more content, on more devices, from more sources than ever – whether it’s movies on our tablets, TV on our smartphones, or files from the cloud.

With no slowdown in sight and new services coming onboard every year, cable providers face a unique challenge to meet tomorrow’s demands on today’s networks.

One answer is wideband DOCSIS 3.0 technology, using dynamic load balancing across available wideband channels.

This can be a nearly universal solution, because most cable providers in North America and many around the world have upgraded to DOCSIS 3.0 capable CMTS/CCAP networks, and because DOCSIS 3.0 devices – like cable modems and video gateways – are on track to constitute 90 percent of all worldwide cable CPE shipments in 2014.

DOCSIS 3.0 Channel Bonding

This widespread adoption of DOCSIS 3.0 network and CPE components enable significant bandwidth increases from technology called “channel bonding,” which combines multiple channels (downstream, upstream, or both) into one, providing multiplicative bandwidth gains resulting in speeds beyond 1 Gbps downstream and 300 Mbps upstream.

DOCSIS 3.0 Dynamic Loading

Optimizing bandwidth from DOCSIS 3.0 networks requires dynamically load balancing channel-bonded modems. These modems have a particular set of channels in which they can transmit and receive upstream and downstream data – Transmit Channel Set (TCS) and Receive Channel Set (RCS) respectively. Users’ bonded DOCSIS 3.0 cable modems often are spread across these channel sets.

Dynamic loading involves periodically checking and comparing the utilization of available channel sets and moving modems to alternative upstream or downstream channel sets with lighter loads.

Moving modems from one channel set to another falls under a function known as Dynamic Bonding Change (DBC), which performs the move in hitless (no loss of registration) operation to eliminate network interruption.

DOCSIS 3.0 Static Load Balancing

Static load balancing is an alternative to dynamic load balancing, but inferior for network optimization, as it involves the CMTS/CCAP assigning a bonded DOCSIS 3.0 cable modem to a TCS and RCS at the time of registration based on modem count vs. channel utilization.

The Path to DOCSIS 3.1

Dynamic load balancing of bonded cable modems allows a provider to stay ahead of exploding demand for both managed and OTT video over IP services.  And, the expansion and efficient use of the DOCSIS 3.0 channel bonding will also enable a smooth path to DOCSIS 3.1 and the ability to compete against fiber-deep initiatives by bonding together DOCSIS 3.0 and 3.1 channels.

Stay tuned for more on the migration path to DOCSIS 3.1...