Deploying CCAP: Not just another box swap
MSOs need to look at operational changes ahead of deployments
As service offerings continue to expand and the end users’ appetite for these services continues to grow, MSOs are putting a tremendous effort into keeping up with the demands on the edge network. Initially, the focus was on the expansion of high-definition TV (HDTV) content. In many cases this was addressed through reducing or removing analog channels, enhanced encoding techniques and through the use of switched digital video (SDV) to allow more content to be delivered to subscribers. At the same time, narrowcast service demands also increased.
Much of this demand stems from growing video-on-demand (VOD) usage, increasing high-speed Internet usage from customers with multiple end devices in the home and new narrowcast services such as nDVR.
To address the need for additional narrowcast spectrum, operators continue to reduce service group size and expand the number of QAMs within each service group. The continued demand for QAMs has resulted in equipment suppliers creating more densely populated designs allowing for the scalability of QAMs per port and QAMs per chassis.
This current trend does not seem to show signs of subsiding anytime soon. The concern is the finite resources, including space, power and cooling, used to handle these expansions within the headend and/or hub.
Expanding the narrowcast spectrum has been very costly for operators in terms of resource and time. CCAP devices will allow operators the flexibility to cable once and grow narrowcast services incrementally. The platform will have the ability to support the entire RF spectrum on a single RF port. This also allows the QAMs to transmit any type of service supporting DOCSIS, VOD and linear QAMs on the same port while reducing the need to modify combining architectures. Non-contiguous QAM support also cuts down on the need for frequency realignments in the markets. With the ability for all the services to be fed out of a single platform, the biggest changes will be the management of those services within a single platform. While many groups within MSOs will be impacted by this change, the greatest impact will be on the operations teams supporting the new platform.
CCAP in a nutshell
Many people are already familiar with CCAP. But for those who are not, here are some important CCAP facts: • CCAP stands for Converged Cable Access Platform • CCAP combines the functions of a CMTS and dense edge QAM into a single platform • Eventually, CCAP implements all narrowcast and broadcast QAMs in a single RF port • Offers many operational features for scaling an all digital network CCAP was designed specifically to support growth in the number of QAM channels used for narrowcast services, such as VOD and SDV, the expansion of HDTV content, and the availability of channel bonding in DOCSIS 3.0 to support higher bandwidth data services.
As MSOs continue to reduce the size of service groups to make more efficient use of their networks and deploy advanced services such as IP-based video and network DVR, even more QAM modulators are needed. CCAP devices will provide the necessary QAM-per-RF-port and port-per-chassis density needed to support this growth while requiring less space and power than currently available equipment.
This results in a reduction of capital and operational costs along with simplified operations.
Why do MSOs need CCAP?
There are many reasons for CCAP success amongst MSOs even before the equipment becomes available. The key reasons are listed in table 1.
While all of the above are important points for CCAP, supporting the growth of narrowcast QAMs is the primary goal of the new platform.
CCAP has the potential to redefine how operators deploy, scale, and manage edge network access.
Video QAM and CMTS equipment is currently deployed across a variety of standalone platforms with the edge capacity managed manually through multiple tools. This equipment requires mechanical configuration by connecting various wires to the signal, combining networks, which is operationally inefficient.
One aspect of CCAP is to allow MSOs to streamline the ability to bring new video, voice, and data services to market faster. CCAP can generate all QAMs used in the cable network, and any QAM can be used for either broadcast, narrowcast MPEG-TS video or for DOCSIS. The use of each QAM within each service group is simply configured via the operational support system interface. A QAM can be changed from broadcast video to narrowcast video to DOCSIS instantly via a change in the CCAP configuration.
Current MSO operations
Today, different groups within most MSOs manage their respective narrowcast services (i.e. VOD, HSI, nDVR and SDV) with minimal interaction and coordination with other teams. And, service group splits result in extensive engineering and headend work to be coordinated between the various teams. These groups often have their own capacity management tools used to determine when a service group split is needed for each service. When capacity is added to these services, either through the addition of QAMs or service group splits, the work is normally isolated to that specific service. This results in each service having it’s own combining architecture.
CCAP will have a definite impact on how MSOs manage new and existing narrowcast spectrum through their edge networks.
Deploying multiple services from a single platform will allow the operator to efficiently deploy and manage new and existing services both in the headend and in the operations centers. Before these efficiencies can be realized, the organization’s engineering and operations teams will need to tightly coordinate design and maintenance activities.
With the ability to generate any type of QAM used in the cable network from a single port, the use of each QAM within a service group is more easily managed and configured via the operational support system interface. A QAM can be changed from broadcast video to narrowcast video to DOCSIS instantly via a change in the CCAP configuration by anyone accessing the box. In the new environment individual devices on the edge will not isolated services.
This means a group working a VOD issue could conceivably impact HSI or broadcast services without realizing it. This is where the greatest impact from CCAP will be felt across multiple organizations.
Operations groups tend to be siloed by service to some degree across most organizations.
In the past, this segmentation was logical due to the different equipment and knowledge required for each service.
Each group could control their service and understand the impacts while remaining unconcerned of impacts to other services.
The CCAP changes this, as all services will be delivered out of a single chassis. With all services handled by a single box, each team now needs to be aware of the impacts to their service, along with the impacts to all other services running on the box.
It will be necessary to prepare network operations organizations that are siloed to manage their services in a single platform, and in the process create new procedures to support CCAP devices. For example, most MSOs separately configure and manage services such as linear video, VoD, voice and data. Services are segmented from a network infrastructure perspective, as well as leverage different tools for each service.
With CCAP, one of the biggest challenges will be to closely coordinate configuration, maintenance, troubleshooting and upgrade activities to not impact other services provisioned on the platform. To address this concern, the CCAP will have the ability to create alarms for multiple services, which could be destined to a variety of support tools and groups within the operator’s environment. With multiple groups working on the platform at the same time, controlled access and privilege levels within the CCAP will be crucial to management of services. This could prompt a review of the roles and responsibilities of many of the support organizations that will manage the platform.
Combining the services within a CCAP box opens up the dilemma of which of the current service organizations will manage the CCAP device, will a single group manage the box or will it be a combined effort? There will be one “reset button” in the end, and its use will have to be coordinated.
Operational support systems
Groups focused on different services usually end up using different tools to manage their services, and new devices need to be modeled appropriately for each tool. In some cases, tools could be collapsed to provide better efficiencies. A key aspect of managing and monitoring new network components has been to enhance existing tools. But, due to the number of services planned to be configured on a single CCAP platform, service configuration processes will need to be implemented. This will aid in the initial configuration, any periodic changes in configuration to support changes as required, and realignment of services as new narrowcast services are expanded.
There are many systems that will need to be adapted; an XML interface for configuration, modified SNMP interfaces for monitoring, change alarm receivers and advanced trouble ticket systems. Additional tools for augmentation will be required while existing tools will need to be modified.
Current ticketing systems need to be retooled to capture all groups impacted with a particular maintenance activity. Today, when a work ticket is opened, the type of service required specifies the appropriate teams to approve the work associated with that service, and other teams not impacted are not notified. For example, a current linear video ticket would not require any HSI teams to coordinate activities. However, in a CCAP deployment, all teams for video and data will need to be notified during the work approval process.
When CCAP becomes available depends upon vendor equipment readiness. Some products are ready already, making it possible to start modest deployments in 2013.
More advanced components should become available throughout 2014.
For all the above reasons, MSOs planning to take advantage of CCAP benefits as soon as the equipment becomes available might chose to address the operational changes that could be required as soon as practical.
Leveraging a CCAP environment would streamline much of the physical work done in headends today, and allow more efficient management of the services supplied through the box. However, the deployment of CCAP devices will have an impact across the operational organizations implementing and managing services on a CCAP platform.
Jorge Salinger is vice president of access architecture, Comcast
Ty Pearman is director of access engineering, Comcast