The term DOCSIS is an acronym for Data Over Cable Service Interface Specification. Several variations of the DOCSIS standard are used by broadband providers.
DOCSIS 3.0 has become the gold standard for home and business broadband across Ireland since Virgin Media introduced it in 2010. It allows ultra-fast speed communications over the existing HFC (hybrid fibre-coaxial) cable networks that are up to five times faster than ADSL’s theoretical maximum.
As of March 2015, 93% of Virgin Media Business customers are benefitting from DOCSIS 3.0 and speeds of 500Mb.
Here is what you need to know about DOCSIS, specifications and hardware.
The evolution of DOCSIS
There are three different levels of DOCSIS specifications; 1.x, 2.x, 3.x.
The first incarnation of DOCSIS, (DOCSIS 1.0) was released in 1997. Throughput was about 38 Mb downstream and 9 Mb upstream.
Over 9 in 10 Virgin Media Business customers are benefitting from DOCSIS 3.0 – the latest generation of this technology – with speeds of downstream 500Mb and 27 Mb upstream.
DOCSIS 3.0 was a game changer because it supports multiple channels, rather than the single channels of its predecessors. Each channel offers the 38 Mb downstream and 27 Mb upstream of 2.0, but 3.0 can bind the channels together to increase speed. There are no limits to how many channels can be used.
DOCSIS 3.1, when it is deployed in 2016, will bring downstream speeds of 10 Gb (10,000 Mb) and upstream speeds of 1 Gb or more.
DOCSIS v DSL– the difference
DOCSIS 3.0 technologies are at the heart of Virgin Media’s Fibre Power network, which makes it a far superior system to DSL-based products. The maximum throughput speeds of DOCSIS 3.0 are five times higher than copper wires in DSL. DSL connections are also affected by the distance between home and distribution point – DOCSIS 3.0 is not. Our fibre network can deliver high speeds without any slowdown at peak times.
DOCSIS 3.0 specifications
There is a 4 channel minimum requirement for DOCSIS 3.0 approved hardware. As faster services are deployed, more efficient use can be made out of these multiple channels and that is what enables Virgin Media Business to continually increase speeds.
To benefit from DOCSIS, both headends must be DOCSIS compatible. That means that you may need a cable modem that is DOCSIS 3.0 certified.
Virgin Media Business supplies modems to customers, so there are no leasing fees and the terminating points are owned by Virgin Media Business.
PHY and MAC – The two layers of DOCSIS
The DOCSIS 3.0 specification can be broken down into two layers, the physical layer (PHY) and the media access control layer (MAC).
The PHY layer consists of the tangible items including wiring and routing equipment. PHY also specifies the frequency at which data is transmitted over the cables of the DOCSIS compliant network.
The MAC layer is responsible for moving data packets through the channels. Essentially, the MAC layer makes it possible for multiple users to be connected to the same physical layer without interfering with each other or impacting on each other’s user experience. Each device accessing the DOCSIS network has its own IP address, but also a MAC address.
DOCSIS 3.1 in Ireland
DOCSIS 3.1 products are coming closer to release. Designed for the Gigabit Era, DOCSIS 3.1 will enable cable operators to offer even faster data speeds. The downstream speeds of 10 Gb and upstream speeds of 1 Gb will be almost 20 times the speeds we offer today.
The specifications for DOCSIS 3.1 were released in 2013. Like with previous DOCSIS versions, the hardware must be compatible with the specification. 3.1 modems will be trialled and tested in 2015. This is likely to be followed by headend equipment trials and early deployments in 2016.
Virgin Media Business is leading the way in bringing the Gigabit Era to Irish consumers and is ideally placed to offer DOCSIS 3.1 as soon as it becomes available.