Welcome back. We are continuing our study of software defined networking applications in the world. And in this lesson we will look at applications of software defined networking, in home networks. Users of home networks, face two challenges. One is achieving the appropriate level of visibility. Into usage and problems that may arise in the home network. Answering even simple questions, such as where the source of a problem is. Or which device is hogging all of the bandwidth, in a home network particular vexing and difficult today. The second problem is providing users with control to help them better manage resources. Usage caps that may exist or be imposed by their Internet service provider, and so forth. Unfortunately, home network configuration can be extremely complex and low level. While your home network may not look quite this complex. Many of us have certainly experienced the frustration of not being able to diagnose problems that arise in our networks at home. Too much of this complexity is exposed to the user. We've experienced some of this frustration in the configuration modules that exist in today's home routers. Unfortunately, current means for managing home networks provide neither visibility, nor control to the users of these networks. Users have a very difficult time. Figuring out the answers to simple questions such as, how much data they have left on a usage quota and when they'll run out? The process by which applications consume both bandwidth and usage are also mysterious and difficult for users to understand or control. And finally in homes with multiple users it can be particularly difficult to understand. Which applications in the home or which devices are responsible, for usage that may interfere with the performance of other applications or exhaust usage quotas. One solution to these network management problems is to apply software defined networking to centralize, and outsource the control of the home network. In our lab at Georgia Tech we have implemented such an SDN control system for home networks. Whereby an SDN controller, sits outside the home network and monitors. Various behaviours and events that occur inside the home. And send commands to manipulate flow table entries on the wireless router inside the home. On top of that SDN controller, we can build more sophisticated features, such as graphical user interfaces. That make the network easier to manage and easier for the average user to understand. The controller that we have deployed is based on the resonant control that we discussed in the last module. In the case of managing usage caps, we have configured that controller. To maintain multiple states for each device inside the home. Depending on how much traffic a particular device has used over particular time window. If a device exceed its usage quota, for a particular time window, we can then use the controller to shift that device's state. From the normal state to a caps state whereby the device is either blocked out right or its ability to use the network is more limited. Lets now look in a little more detail at two specific applications of SDN control in home networks. The first is the home network management application that we just talked about briefly. Moving the STM controller out of the home allows for more flexible control and management models for a home network. Potentially even creating the possibility for third parties to manage the network. Moving this control off the home router also makes it possible to develop remote control and better user interfaces for home network management. The second application, is what is called slicing of the home network. That is virtualizing the network infrastructure, to allow service providers direct access to the home network infrastructure for tasks such as video streaming, smart grid applications and so forth. Let's now take a look at the first application in a little bit more detail. A key problem in home network management, is usage control. Many internet service providers, have begun to impose usage caps on their users to limit or control the amount of data that a particular user uses over the course of a billing cycle. Unfortunately users may have a very difficult time understanding how different devices inside the home consume that usage cap. And an even harder time controlling the devices that may be hogging all of the usage quota. To mitigate this problem we have developed a system called UCap. Which allows users to see how different devices in the home are contributing to their overall monthly network usage. Equally importantly, the user can use the interface to control and limit how different network devices consume that usage cap. Perhaps the most interesting part of this system. Is that, all of the machinery under the hood, is implemented with the resonance SDN controller. Here's an example of the UCap interface in action, for a real home network. On the left, we can see a list of devices, some of which have been labeled. As well as a bunch of other devices, that user has not bothered to label. The pie chart in the middle shows a breakdown of network usage for this particular month by devices. The history tab shows which devices consume the most data over the course of a particular time interval, as well as the top domains for this home by traffic volume. In addition to providing the user better visibility, UCap also provides the users better control over how devices consume data over the course of a month. A Manager tab shows all of the devices, and allows a user to set a usage cap for a particular month. When a user sets a usage cap the controller then listens for an event. That indicates that that particular device has exceeded the usage cap for that particular month. When the controller receives that event, it shifts the state of device from normal to black until the billing cycle. Other applications for SDN in the home is slicing. Consider a situation,where different service providers, such as a smart grid provider, and a video streaming provider. Each want access, to different resources or infrastructure in the home network. Many of these service providers want to offer services to home users with guaranteed performance and reliability. Unfortunately, it is very costly to have each of them deploy their own network infrastructure. A solution to this problem is to slice the home network. Such that each provider, controls a different slice of the infrastructure or resources, using the flow space concept that we saw earlier in the course when we looked an flow visor. In summary, home networks can be very difficult to manage. Because users have very limited visibility and control over what is going on in the home. Service providers who may want to offer value at its services also have limited access. We've looked at two applications of SDN in home networks, usage cap management and slicing of the home network. Each of which illustrate how the use of SDN to refactor control in the home network can make home network management much easier, both for the users and for service providers. [BLANK_AUDIO]. And for service providers.
