For the past several months Comcast been building a new policy engine for orchestrating Quality of Service (QoS) on our network and now we’re excited to begin contributing key parts of that engine available to the open source community.

QoS is a critical function for network operators. On our DOCSIS network, QoS technology is how we ensure that essential functions are allocated enough bandwidth to perform at the highest level. A good example is a voice call, which needs a certain amount of dedicated bandwidth to be crystal clear and without jitter.

PacketCable Multimedia (PCMM) is an extension of the existing CableLabs PacketCable™ specification that enables a DOCSIS-based ISP to implement Quality of Service (QoS) via DOCSIS cable modem connections to deliver enhanced IP voice, video, data, gaming, and multimedia applications. 

We’re calling the new engine we’ve built to orchestrate the PacketCable specification, PacketCable Multimedia Next Gen (PCMM-NG). PCMM-NG uses software-programmable service flows through the integration of an OpenDaylight (ODL) PCMM plugin and an open source DIAMETER library. PCMM-NG also enables practical use of Software Defined Networking (SDN) concepts and technologies in a DOCSIS network.

Figure 1 illustrates the complete PCMM-NG framework, defining a collection of elements and interfaces that together support the service objectives of Dynamic QoS (DQoS)-enabled capabilities.

Illustration of PCMM-NG framework.

Figure 1: PCMM-NG Architectural Framework

PCMM-NG benefits from a more dynamic and robust network control promised by Model Driven Service Abstraction Layer (MD-SAL) based SDN, thus turning it into application that deals with software models of network devices instead of directly dealing with actual devices. PCMM-NG leverages ODL to enable role-based authentication and authorization, distributed, concurrent, fault-tolerant, and scalable application. 

In our first PCMM-NG release, we will deliver a subset of features needed to support the use cases and requirements necessary for an eventual complete SDN implementation. For the purpose of our application, two specific use cases within the DOCSIS policy infrastructure in the PCMM architectural framework are addressed in our initial release:

  1. Telephony – The application of QoS to manage enhanced IP-based voice traffic.
  2. Notification – The application to provide real time web browser notification for communicating with customers (as described in RFC 6108).

We plan to submit our open-source PCMM-NG contributions for inclusion in the next Open Daylight release, Carbon.

We expect PCMM-NG to be very cost effective and low maintenance product as compared to commercial PCMM alternatives.

We presented a PCMM-NG project paper at the Internet and Television Expo [INTX] 2016 on May 17th in Boston. In addition, we’ll be illustrating how our ODL PCMM plugin is evolving and expanding at the OpenDaylight Summit 2016 in Seattle, WA on September 27th. Until then, check back here for more about how we’re making PCMM-NG work for us.