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November 21, 2008

Networked Homes and the Network Chasm

By Bob Emmerson, TMC European Editor


IPTV (News - Alert) services have taken off and growth is impressive, but the technology and the systems are proprietary, which means that the service as well as that of triple play is tightly coupled with the IAD (Integrated Access Device) of the network provider. This is a short-term model that works, but there’s a network chasm that has to be crossed before we get to open systems and networked homes. 

There’s a chasm between today’s VoIP/IPTV/Triple Play (News - Alert) services and tomorrow’s digital, networked home. It’s the elephant in the room. Right now services are tightly coupled with the IADs of network providers. They’re coupled because as shown in figure 2, broadband access is combined with a router and firewall as well as other functionality, e.g. a VoIP client. IADs work since the provisioning standard for the access is logically connected to the VoIP endpoint inside the IAD. However, it falls over when VoIP is in an endpoint device located behind NAT and firewalls.  The endpoint client can call out and traverse the chasm, but the management server cannot call in.  

Everything works when everything is in front of the chasm — when there’s nothing to cross, no NAT issue — but this scenario represents a closed environment: the service provider controls and manages the access network. Given the size of the investment that has to be made in IPTV and Triple Play it’s the only model that makes business sense right now and it’s also the only way to create the market. However, it is somewhat ironic that the services that IP enables do not reflect that of the open Internet model. 
Convergence (News - Alert) in the home
Network cores, both those of fixed and mobile network operators are migrating to IP and they use, or will use, the same service and creation platform: IMS. This means the core of public networks is flat: access, however, is vertical, e.g. the same service can be employed via mobile phones or Wi-Fi devices. A similar development is taking place in the home, as shown in figure 1. 

There are technical and business issues that create the network chasm visualized in this schematic. The technical issues concern the fact that access standards don’t have the requisite functionality for the service endpoints. They only provision the modem and NAT/firewalls create the chasm: they can’t jump over to configure and monitor applications and services on endpoints like standalone ATAs and IP Phones. When this issue has been addressed the market for the networked home will be able to realize its full potential.

Figure 1. The residential network is flat and services are delivered via cable, xDSL or fiber to the home (FTTH). However, in this case there are access issues that have to be addressed in order to realize the full potential of these services as well as the concept of smart, digital homes. 

The business issue comes from the need for co-operation and agreements between the owner of the access network and the application service providers. There is only one access route, but all services across the whole residential network need to be delivered with the best possible QoS.

Converged services

Righty now we have propriety solutions and a short-term model, but the market will only realize its full potential when third parties are able to offer additional services and new end point devices. The devices that function in this vertical domain must be certified and approved by the provider of the access service and must comply with the relevant provisioning standards, which will be TR-069 in the case of DSL. A similar tight coupling is also required when access is enabled by cable modems. In this case the devices have to be compliant with DOCSIS.
Figure 2. Media attention tends to focus on different winner and loser scenarios (telcos versus cable operators), but nobody will win in the long term until the ‘network chasm’ issue is addressed. Horizontal, open integration is the long-term solution: the only way to make a consumer market for residential services in tomorrow’s digital homes.

TR-069, DOCSIS and SNMP (fiber) are robust access standards that perform the tasks for which they were designed, but real-time services for digital homes have different requirements. Vertical integration works well as a short-term solution: it kick starts the market, but open integration is essential. It is clear that the provisioning and monitoring of third-party services should get equal access rights in order to deliver the best possible QoS to subscribers. For example, the quality of VoIP from an ATA should be the same or very similar to that of VoIP from an IAD.

A pragmatic approach

There are numerous examples of innovation being based on a proprietary semi-proprietary approach in order to create a market and that is the current situation. Owera (News - Alert) ( has proposed and is delivering a client-server solution that augments these standards: in addition it allows the full potential of the networked home to be realized. It is not a workaround, a band-aid fix: it’s a high-level provisioning technology. It does not attempt to overthrow the model that is creating the market. Instead the primary objective is to facilitate its development via the addition of functionality that works for consumers as well as service providers and retail outlets.

Einar Aaland (News - Alert), CTO: “Standards can evolve: extensions can be added but they cannot take on new roles. Access provisioning standards cannot add application management, QoS monitoring, troubleshooting and real-time diagnostics. Moreover these tasks have to be performed all the way from the endpoint/application and not only from the access device. Workarounds are also done by proxy traffic through other provisioned devices, but this does not necessarily open up the market.”
If workarounds aren’t working now what needs to be done? If access-provisioning standards stop at the access device then it is clear that a client-server solution is needed, i.e. client software has to reside in the end points so that they can be provisioned, managed and monitored by a server in the cloud. It’s also clear that this has to be a very small client: it is impractical to embed provisioning clients that are measured in Mbytes in devices such as printers and cameras. And the client has to be access agnostic so that these devices can be sold via regular retail outlets. 
Figure 3. The red line indicates the logical connection to the management client inside the access device. The blue line indicates the logical connection between the OPP client inside the service endpoint and the xAPS server.
Owera’s solution is based on complimentary software designed for applications and service management and as illustrated in figure 3, it uses the client-server model. It can be used in conjunctions with TR-O69 and DOCSIS, standards that were designed for access. The embedded OPP client (Owera Provisioning Protocol) software is light software (only 10s of kilobytes). OPP traverses the chasms and keeps the logical connection open for the server to be able to call in.  
The xAPS server provides a scalable, high-performance (millions of devices at the same time) platform. It can configure and activate a service, monitor and manage the devices and the application/services it runs. In addition, several modules can be added to extend the functionality.  xAPS also has the ability to run different interfaces simultaneously, e.g. TR-069 and OPP. This allows the same server to manage the widest possible range of devices, services and IP endpoints. As well as being convenient, this feature ensures that all services get the optimum QoS.
The server works in client-server mode with endpoint devices that have the embedded OPP client, thereby providing them with additional functionality and value-add features. This allows them to participate in network management functions and network forensics such as route mapping, NAT/firewall detection, as well as service diagnostics like MOS logging for VoIP endpoints. In addition they can detect changes to the residential network or network connection.
The ability to enhance the functionality of the end-user devices in this way gives service providers a real-time, high-level view of the consumers network and the service as experienced by the end user, which is the one that really matters!

Bob Emmerson is TMC's (News - Alert) European Editor. To stay abreast of the latest news affecting the European market, check out Bob's columnist page.

Edited by Michelle Robart

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