General

DSL Forum Makes IPTV Easier

The standards body says that ISPs are eager to deploy IPTV, but have many concerns about it too.

by Alex Goldman ISP-Planet Managing Editor [January 15, 2008]

Some changes start with a ripple, others with an explosion, and, these days, some start in an industry working group. In December, 2007, the DSL Forum released TR-135 [.pdf, 114 pages]. The new technical report covers the delivery of IPTV services to the home and contains several items of interest to ISPs that are using or contemplating a deployment of IPTV.

The work builds on DSL Forum's TR-069 from the previous year (see DSL Forum's New Direction). In TR-069, the Forum focused on open standards applicable to all broadband services, not just DSL, an initiative it calls the "Broadband Suite" and that is a significant new direction for the Forum. It is a welcome change, as many service providers today do not fit within one category. They are using a variety of technologies and providing ever more services over their hybrid infrastructure.

Function at the junction
TR-135 focuses on actually getting the service to work. Heather Kirksey, DSL Forum Director and also Motive, Inc.'s Senior Manager for Emerging Standards and Technologies, divides that into four categories. device configuration, troubleshooting and diagnostics, performance monitoring, and firmware and image management. At every stage, she says, from installation through upgrade and eventual replacement, the standards are being designed with the service provider's needs in mind.

She says the Forum's focused on "what's required to make these services easy to roll out and easy to provision by the end customer, which reduces the ongoing costs associated with them (such as by reducing truck rolls). We're reducing the ongoing costs associated with the help desk by making it easier to proactively solve or solve faster any problems that occur. Firmware management is improved by enabling upgrades in software (versus replacing the hardware) especially bug fixes, but also enhanced capabilities. This reduces capex and improves the service provider's long term profitability."

So how soon will all of this be available? Laurie Gonzalez, DSL Forum Marketing Director, notes that many equipment makers participate in the DSL Forum to get ahead and could have products in the second quarter of this year. "They have proactively aligned their development cycles," adds Kirksey.

The design
So will the new set top box replace the traditional gateway and modem setup? Not for now, says Kirksey. ISPs appear to be preparing to add the new set top boxes to a setup involving equipment they already know.

Of course, the set top box will interact with several devices that the gateway and modem never connected to. The set top box will be able to connect to a home entertainment system, including stereo and television. It will also be able to connect to a storage device, as defined in TR-140 [.pdf, 46 pages], that could function as a personal video recorder (PVR) or media hub.

The capabilities of devices are modular, so in the future it will be possible to have one device that combines the functions of several. We're starting to see that in networks, in devices such as routers and filters that ISPs are comfortable with, but not in cutting edge appliances such as IPTV hardware.

The designers at the DSL forum appear to view devices as logical function stacks (see image at right) rather than as specific boxes with defined connections. Asked how the devices will connect to each other to share content, Kirkey points out that other standards groups are working on this issue, such as the Universal Plug and Play forum and the Digital Living Network Alliance.

The data
At the core of the new specification is the area that ISPs seem to have been most concerned with: controlling and monitoring IPTV service. ISPs will be able to obtain detailed information about the functioning of the CPE and of the service being delivered.

Kirkey says the distinction is important, and requires providing two sets of data to the ISP. "There's a service management layer and a content interaction and session control layer. For the content layer, ISPs are concerned about being able to get statistics for ports used and iframes or pframes that were dropped."

Less video-centric information will cover the condition of the pipe, measuring metrics that all ISPs are already familiar with, such as latency, jitter, and dropped packets.

The DSL Forum expects ISPs to distinguish between incoming streams and outgoing streams. Incoming streams could be revenue earners, such as pay per view (PPV) content or traditional television. "A lot of service providers want to deploy a managed backup to media servers. Others are considering partnering with a company to provide targeted downloads onto a media server that can stream to other devices."

If there's an issue, service providers will have many options. "A service provider might need to change the network, not just the set top box," says Kirksey. "It's part of that end to end view of the network. They might need to tune something in the media delivery platform."

For money to be made on all of this, all devices must connect reliably to backend servers for billing and authentications.

The future
There's still plenty of work to do on the DSL Forum's Broadband Suite initiative. Performance information is very important. There will be additional performance information, the ability to obtain information about the performance of the home network, additional gateway management capabilities, and cooperation with more networking groups (such as HomePlug, HomePNA, and the MoCA Alliance).

The DSL Forum will also be examining new areas, such as Fixed-Mobile Convergence (F/MC) in video, "multiple screen paradigms, mobile phone and TV to access and render content," says Kirksey. "It is on the horizon in the industry, and is something we're beginning to turn our attention to."

Bandwidth is a worry for some ISPs deploying IPTV, and the DSL forum is looking at ways to increase speeds, such as DSL bonding and, of course, fiber. What about DSM? "We're looking at DSM," says Kirksey. "We had an informational session and Cioffi came in. We're driven by our service provider members. It's up to them to decide whether a particular technology needs standards work and whether the DSL Forum is the right place to do it."

Finally, Gonzalez notes that ISPs may be interested in IPTV white papers that the DSL Forum will publish later this year. There will be two: one covering best practices in installing IPTV and one covering best practices in configuring IPTV. They are scheduled to be published in the middle of 2008.

—End