Why not multicast all of the way down?

Mahmud Noormohamed, Net Insight’s VP business development North America, thinks there’s a much better way for telcos, particularly those in rural areas of the United States, to approach their IPTV roll-outs.

They would be better served by aggregating hundreds of encoded television channels at a headend and routing them all down to DSLAMs, he says. That way issues with IP overhead or those associated with packetizing video can be avoided.

But that’s just half the story. The same aggregated channels from a single headend can be shared via OC-192 links so other rural telcos can launch IPTV services to their customers without the CAPEX required to build their own headends.

IPTV Update: As Net Insight approaches telcos about IPTV service, what are their common requirements at their video headend to manage and aggregate incoming video for IP/MPEG-2 or IP/MPEG4 routing to the network backbone?

Mahmud Noormohamed: In the U.S., we are only talking about the rural telcos. We are looking at independent IOCs really. Our proposition there is consolidate —virtual headends rather than fixed head end per rural telco. The underlying factor is that if you share, it’s a lot cheaper.

So that is the approach we are taking, and it is resonating with the consumer for many reasons. One is the negotiations per rural telco with the content companies is quite laborious and long. So if the rurals can get together and negotiate once and then share an infrastructure, it obviously benefits them.

IPTVU: Who’s currently employing this strategy in the United States.

MN: We have three triple play solutions here in the U.S. — Midwest Tel Net, Vernon Telephone and Matanuska in Alaska.

IPTVU: As you approach telcos in rural settings, how are you finding their interest in MPEG-4 vs. MPEG-2?

MN: From our technology perspective, it doesn’t make any difference whether it’s either of those formats or it’s uncompressed. Our play is if you transport uncompressed, you can share the quality of the technology and when it gets compressed, you’re superimposing the quality that we’ve already demonstrated.

From our perspective, it is irrelevant, but from the rurals’ we definitely are seeing a trend toward MPEG-4. They do need it to offer HD channels, and really the only way they can acquire them and transport them in terms of infrastructure is through MPEG-4. So they are deploying trials in that effort.

IPTVU: Have you found the rural telcos to be up to speed on the QoS demands of video in an IP network?

MN: We guarantee 100 percent QoS, so whatever comes in will come out of the other end without any latency, jitter or wander. Our play is to measure and manage all of that because our infrastructure will guarantee it.

IPTV: How so?

MN: Because we are a Layer 2 protocol, so we don’t have the IP overhead or issues associated with packetizing video. We are a synchronous transport, so we are kind of the TDM of the IP world. That removes 80 percent of the problems. Our play is take video synchronicity to the local loop before you put it through an IP infrastructure. That way, you can avoid a whole bunch of management overhead.

IPTV: How is Net Insight’s Nimbra being deployed at IPTV headends and being used for local distribution?

MN: We are being deployed at headend aggregation, pre- and post ingress, meaning we do support companies that are delivering to the headend — digital media services from their broadcast center. And then post headend we are distributing into the local metro area. We do not do access, so we terminate at either VOD or DSLAM.

IPTV: So all of the channels that are aggregated are present down to the DSLAM?

MN: Correct. De facto from our technology, we multicast everything to every point in the network.

IPTV: Isn’t that a big departure from other IPTV architectures?

MN: Yes, it is. From our perspective, you are basically distributing all channels to the local consumption point, so you will avoid quality degradation at the start. Then the consumer is getting the response rate and the accessibility of the infrastructure because all of the content is pretty local, and the IP overhead is maintained at the access layer and does not have to travel through the core. That’s where you get the delays and the channel changing issues. That’s how we position our technology.

The way that we optimize and use the bandwidth, it’s efficient to do it and distribute it that way.

If it was just an IP infrastructure and you’re doing switching at Layer 3, then you get all of the overhead and bottlenecks associated with packetization. So from a video perspective, we’re saying, “Why not multicast all of the way down?”

IPTV: How is Net Insight addressing the VOD side of the IPTV business?

MN: From the implementations where we’ve had experience, we keep the VOD servers close to our nodes. So the latency between the VOD server is very minimal. In fact, they share the same infrastructure and sometimes sit in the same rack. So the communications channel between the two is a very short distance. You do not see the degradation associated with the latencies in the packet network because we are right next to the device itself.

As VOD plays out over one of our nodes, we take it to the access networks and to the DSLAMs directly. So it’s minimal impact, minimal infrastructure issues associated with that kind of configuration.

IPTV: Is there anything else you’d like to add?

MN: Virtual headends are a must for these guys. We’ve done ROI analysis, and the other offerings are very, very expensive compared to sharing infrastructure and sharing common VOD servers. So the rural telco market is very much going to be a community-based infrastructure. I cannot see projects like Lightspeed or FiOS taking place in that market. I think we are a good fit for these guys who want a lean, mean IP video experience.

IPTV: How far can you take the concept of a virtual head end? Do you see the possibility of a large number of rural telcos spread apart geographically forming into coalitions to share a headend?

MN: This week we spent time with three companies in the rural Minnesota area discussing how they can gain access to the infrastructure that’s already in place through fiber optic connection. This doesn’t just go into sharing content rights but sharing content administration systems, subscriber management systems, video servers and so on. You’re just adding subscribers.

IPTV: But is there a physical limitation, or is the speed of light the speed of light so it doesn’t make a practical difference how far the virtual headends are apart for the real headend?

MN: Correct. We’re looking at OC-192 links between these sites and off we go with 200 plus channels, and we just propagate across the U.S. geography by geography. Now obviously we’ll have to build in another headend somewhere so there’s redundancy in case a super headend fails another one kicks in, but then they are sharing infrastructure and it’s a per-subscriber fee rather than a CAPEX expense to build the infrastructure.

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