4.5 Gbps Achieved over Cable Connection

ISPs trying to get the most out of their cable networks are going to be quite excited by the latest developments in the field which promise download speeds of 4.5 Gbps, quite a big improvement over the current max speeds achievable with DOCSIS, the technology used by cable providers to add internet services to their infrastructure.
Arris, a company that specializes in networking equipment for cable providers, has announced that it will be showing off its latest hardware capable of this impressive speed, albeit with a few caveats.

"ARRIS today announced that it will demonstrate two DOCSIS 'firsts' at NCTA 2011, in Chicago," the company said.

"The demonstration will show real file transfer throughput of 4.5 Gbps of DOCSIS downstream traffic being transmitted over 128 DOCSIS downstream channels into a single Fiber Node," it announced.

The company can achieve this speed by using up more channels than the current DOCSIS (Data Over Cable Service Interface Specification) implementations do. This means that there are fewer analog TV channels left, but providers will probably find it a worthwhile trade-off.

"In the demo, an ARRIS C4 CMTS will be configured using four newly-released 32 Downstream Cable Access Modules (32D CAMs) to source the 128 DOCSIS downstream channels into the Fiber Node," it explained.

"The demo will also show a proof-of-concept implementation of a 5-200 MHz high-split DOCSIS upstream system with 575 Mbps of DOCSIS upstream bandwidth being transmitted over 24 DOCSIS Upstream channels out of a single Fiber Node," it added.

As users get more and more used to viewing online video, in HD, playing games or getting their movies in minutes rather than hours, ISPs struggle to keep up.

Bandwidth gets increasingly expensive as it nears the users, the biggest investments these companies make in infrastructure are for the so-called "last mile," the portion that gets the data to the actual user.

Especially in areas where subscribers are spread out geographically, ISPs are always looking for ways to maximize the use of their existing infrastructure, be it telephone lines or TV cable, rather than upgrading it to fast but expensive fiber-to-home connections for example.