Communicate

How Multicast Will Improve NBN Video Services

The National Broadband Network (NBN) officially launches multicast services today, which allow internet providers to distribute video content and other large files directly to each of the points of interconnect (POI) on the network, making them faster to access and cheaper to distribute. How quickly will that option roll out and how will it change the way the NBN gets used? Lifehacker chatted with Jim Hassell, NBN Co’s head of product development and sales, to get the lowdown.

Picture by Adam Pretty/Getty Images

“Multicast allows service to deliver broadcast-type content and to inject that into the network once and to get that out to a large number of end users,” Hassell told Lifehacker. “It makes the network efficient for IPTV services, and means providers can potentially build-up triple-play bundles very easily.” Because the content is distributed directly to the POIs, backhaul costs are cheaper.

Bundling isn’t a new development; many ISPs will try and sell you entertainment content and mobile services right now, and current NBN plans frequently include phone rental options. However, it becomes much more appealing with a high-speed network such as the NBN, which can potentially deliver content at 4K resolution.

Higher upload speeds also mean that TV networks can examine more interactive features. “One of the challenges for broadcasting is how to make those programs more interactive so people hook in on a live basis,” Hassel said.

Multicast is an option for internet service providers, not end consumers. While NBN Co charges those service-providers on a per-customer basis, you won’t see ‘multicast’ as an element on your bill. Instead, that cost will be factored into the overall charge you pay for the services you want from your chosen provider.

The NBN is planned to have 121 POIs each serving around 150,000 premises, and multicast features will be added to them gradually over the next 18 months (Brunswick in Victoria is the first to get the option). While service providers can sign up for multicast from today, it will still be a while before we actually see any NBN providers offering bundles that combine internet access, phone services and entertainment channels. There are a number of reasons for this.

Firstly, any provider wanting to offer multicast has to go through an “onboarding” process, which typically takes around a month. Secondly, the current multicast pricing mean it only makes sense once a provider has a critical volume of users. “You’ve got a crossover point with it in terms of the number of users where it would make economic sense,” Hassell said. “That crossover point is around 160 to 170 users. Up to that point they’re better off injecting the content as it is.”

Multicast also relies on the NBN itself expanding rapidly. “The big thing for us is the transit network,” Hassell said. “Because it uses a large amount of bandwidth, you can get a huge number of high-definition channels across this, so we need to have our transit network in place so we can deliver it cost-effectively.” The target date for the transit network completion is 2015. We might see some bundled services before that, but for most ISPs, having national scale will make sense.

Multicast isn’t designed specifically for video, and can be used with any data that needs massive distribution. “The way the product is built, you can take any bit of content that you want and inject it through the multicast domains,” Hassell said.

However, the pricing model NBN Co has adopted is designed with larger files in mind, since it charges the provider $2 per user for the first 5MB of data. That model wouldn’t work with smaller files such as software updates. “If you were injecting content or smart meters, that would be overkill,” Hassell said. “You’d need a smaller increment than that.” NBN Co plans to introduce more granular multicast models in the future, but will be driven by service provider demand, Hassell said. “We’ve designed it with the IPTV market in mind, and the way the product is structured and priced reflects that.”

While large providers such as Telstra already have content deals, many ISPs are likely to sign deals with third-party content providers such as FetchTV instead. At this stage, even though the content across those channels is identical, each provider would need a separate multicast deal and would have to send that content to the same POI.

NBN Co recognises that’s a potential issue. “At the moment, each provider has to take that content and put that in,” Hassell said. “We’ve been asked by everybody if there’s a way we can inject once and not have it done multiple times. In principle, we’re quite OK with that. The challenge we’ve got is that it’s not our mandate to go past Layer 2 services, nor is it our desire to be responsible for content We’re working through those to figure out how can we do that, so that’s something for the next couple of years.”

Future plans also include extending multicast beyond the fibre network that will service the majority of NBN customers to the wireless and satellite options that cover remote areas. “At the moment, the product is just available for fibre. We are looking at developing it for wireless and satellite and have done quite a bit of work on it. You have different challenges because of the bandwidth and availability.”

So why wasn’t multicast introduced right from the start on the fibre network? “It was always a conscious plan,” Hassell said. “We built the product roadmap two years ago. We decided we would aim to bring the product out that would hit the biggest volume of the market, and that was consumer market broadband and telephony over fibre, wireless and satellite. Next was multicast, and we’ve just started with business services as well. It really is a question of a planned progression.”

NBN Co