Virtual reality, while not a mainstream technology as of yet, still holds promise for emerging applications like patient management and immersive gaming. As cable broadband architectures shift, new technologies are poised to help operators handle requirements for enhanced experiences.
While 5G has been touted as a VR-enabler, the cable industry has also been at work developing and implementing technologies to reduce latency, improve WiFi capabilities, and increase speeds and capacity, all needed for immersive experiences.
In an October presentation, Qualcomm indicated that next-gen 360° video including features like 8K, 90+ frames per second, HDR, and stereoscopic video will require 50 to 200 Mbps, while immersive VR/AR experiences including free-viewpoint or 6 DoF (6 Degrees of Freedom) will require anywhere between 200 to 5000 Mbps speeds.
CableLabs’ DOCSIS 3.1 technology enables cable broadband networks to deliver 1 Gbps service and has already been deployed by major operators including Comcast, Cox Communications, Charter Communications, and Midco, with each now offering gigabit speed services.
Belal Hamzeh, senior vice president and CTO at CableLabs, said that gigabit service is currently available to more than 80 percent of cable customers in the United States, up from just 4 percent in 2016. Cable broadband service of 200 Mbps or better has also increased, jumping by more than 200 percent from late 2014 to June 2017.
Hamzeh noted that this is only the first step on the CableLabs 10G platform, which was introduced by the organization in January, along with NCTA and Cable Europe. 10G builds on the 1 gigabit-capable network infrastructure that’s already in place in cable broadband networks to eventually provide 10 Gbps and greater symmetrical broadband speeds.
“Leveraging DOCSIS technologies, the 10G platform has a path to support 10 gigabit connectivity with high reliability, high security and low latency to the end user,” said Hamzeh.
When it comes to networks, Chris Bastian, SVP, Engineering and CTO of SCTE/ISBE, says cable HFC “continues to show its flexibility and versatility.” Bastian noted there are several tools that can be used to continue increasing downstream and upstream speeds, but acknowledged that operators don’t need to employ all of them to hit the speed point they want.
“Full Duplex [DOCSIS] is one tool, where upstream and downstream will share the same frequencies. Another tool is moving the mid-split, or going to a high-split or top-split, to allocate more spectrum to the upstream,” Bastian said.
Enhanced WiFi Experience
When at home, most people use a WiFi connection to access the internet, and when talking about services such as VR, Bastian says it’s important to consider end-to-end speed, which includes the WiFi segment.
“Like the HFC, Wi-Fi is constantly evolving. Wi-Fi 6 (or 802.11ax) will provide greater security, greater capacity for multiple users, greater power efficiency, better coverage, and yes, greater speeds,” Bastian said. “Multi-gigabit speeds will be supported by Wi-Fi 6.”
CableLabs’ Hamzeh noted that a main challenge for operators ensuring consistent and reliable WiFi connections is the popularity of WiFi.
“With Wi-Fi being the preferred method for users to consume their broadband experience, in addition to significant growth of connected devices per user in a household, it leads to congestion in the Wi-Fi network thus impacting network performance,” said Hamzeh.
Just this week CableLabs introduced new Dual Channel Wi-Fi technology, which aims to reduce congestion and create a better user experience. It addresses the congestion and impact to network performance by enabling a secondary Wi-Fi channel that can be used for certain applications based on defined parameters. So in addition to the primary bi-directional channel, additional channels are provided for downstream-only data, achieving better airtime utilization for traffic and fewer interruptions.
Hamzeh gave the example of the secondary WiFi channel dedicated to video streaming traffic or large file downloads.
“This helps alleviate overall network congestion and increasing available airtime in comparison to a network running two Wi-Fi channels without any traffic management across the channels,” Hamzeh explained. “The reduction in network congestion and the increase in available airtime allows all devices to achieve better performance.”
Dual Channel Wi-Fi is also compatible with Wi-Fi 6.
Cutting down lag time
Latency in VR is critical for an enjoyable experience, with less than 20 millisecond latency required for a nausea-free experience.
It will become increasingly important for things like healthcare applications. An April report from BIS Research forecast the global AR/VR healthcare market to grow to more than $11.14 billion by 2025, at a CAGR of about 39 percent.
A separate report from Reports and Data found the North America region accounts for the largest share of the global VR healthcare market, making up 44.21 percent. Though the firm found the VR Healthcare market will only reach an estimated $6.91 billion by 2026.
Earlier this year, streaming media platform GIBLIB launched a VR app offering an immersive operating room experience to enhance surgical education using 360 VR and 4K. In March, research presented at the Society of Interventional Radiology’s 2019 Annual Scientific Meeting showed immersive VR could allow interventional radiologists to improve treatments using real-time 3D images from inside a patient’s blood vessels.
The Reports and Data findings suggest patient care management applications will lead the market for VR in the healthcare segment, predicting that segment will to grow at a CAGR of 16.6 percent by 2026.
“The use of AR and VR in therapies and rehabilitation would boost the virtual reality in healthcare market. The rehabilitation includes brain injury, stroke, and physical therapy among other applications,” the company found.
Columbia University researchers developed a virtual reality application for remote interactive physical therapy between patients and doctors. This application was tested at Verizon’s 5G lab in New York City, and researches said low-latency connection was key to enabling real-time, uninterrupted transmission so both participants could experience interaction and feedback
While reducing latency in mobile connections is a major focus of the wireless industry, it’s also important for cable broadband.
SCTE’s Bastian explained that there are three main sources of cable broadband network latency:
- The transmission medium, whether it’s copper, fiber or air, delays packet transmission, based on the medium’s physical nature.
- The network elements attached to the physical medium, such as routers, CMTSs or application servers, add latency.
- Any storage elements where the packets may “rest” will add latency to retrieve the packets.
He noted that CableLabs is currently working on multiple projects to reduce network latency including two major cable access network technologies, DOCSIS and WiFi.
Current DOCSIS 3.1 networks already include a feature known as Active Queue Management (AQM), which significantly reduces latency. The ultra-low latency required for future VR applications is not far out of reach. Both Bastian and Hamzeh pointed to recent demos that decreased latency to single-digits and as low as just 1 millisecond, using the latest suite of DOCSIS 3.1 specifications that include Low Latency DOCSIS (LDD) technology.
CableLabs says that LDD technology can be widely deployed to all cable broadband subscribers without major new network infrastructure deployments and compatibility with existing hardware.
VR Still Emerging
Even if networks are up to the challenge of VR, there is still a need for availability of devices and applications. Findings from Parks Associates found that only 8 percent of U.S. broadband households own a VR headset. Of those that do own VR headsets, 55 percent feel that content for their device has remained the same since they purchased their headset and 3 percent believe it’s gotten worse.
According to Parks Associates, costs, demands for interactivity and limits on content length are the main barriers for VR content development.
Facebook-owned Oculus Quest was just released, a fully standalone VR headset that the company hopes can help generate more mainstream appeal for VR.
While new applications are still emerging, services are an increasingly important consideration as cable broadband providers look to new network architectures and technologies.
“Historically, the attention was focused on the network, and promoting its capabilities, for example via speed test. More and more, the operator’s focus is on the customer’s experience with their services, whether gaming, video, VR or other emerging services,” said Bastian. “In the past, the services were secondary but they’ve now become the primary cable operator focus.”