 Now we are going to look at the ubiquitous sensor network services So what is ubiquitous? It's a basically Latin word ubiquit, which means everywhere So these are the services which are sometimes provisioned through the web services like architecture and Sometimes through other proprietary means So it's a very diverse and broad field Normally it is referred to as wireless sensor networks But in the context of NGN these are known as USN services So we start with an overview. We'd understand what is the network like? What are the major technologies involved and how is it evolving? so it is an emerging service that is to say these services are getting increasing acceptance and Pervasiveness in the user community. So ubiquitous sensor network services has the next important component known as Sensor. So these are the physical sensors or the logical sensors which sense the environment This environment can be the physical environment like Habitat monitoring temperature, etc. Or sometimes it is the logical environment for instance the presence and location Detection so it has a lot of applications because these sensors together form a network and they have applications in entertainment industry infotainment Government public sector Education, etc. So USN in the context of NGN defines a conceptual framework or a Model through which these services can be transported from the physical networks Which are very different and diverse and heterogeneous to the NGN users So essentially these are also known as the knowledge services because the journey from raw data To information to knowledge actually is the desired goal for inferring the maximum purpose and usefulness from the real-world environment So the network is basically a wide come wireless network because these sensors are Connected to each other and to a centralized system known as the gateway and the The portal Which in turn is connected to the NGN So These services of a sensor network are fairly autonomous because different service providers come up with their own ideas and with their own Mechanisms to provide these services through their own devices and gadgets So if all these devices in the sensor network are working together, it is known as the cooperative or Distributed processing environment So if these sensors are working cooperatively, it means that we are looking at some kind of synergy or support behavior and some redundancy and some Reliability so that is why sensor networks have a lot to offer in terms of research and in terms of applicability They these sensor networks can be deployed in a variety of environments like plant automation like factories control controller area networks security and safety systems as in shopping malls fire Detection prevention and alleviation based forest sensor networks Basically HVAC related office automation and home automation For example smart homes green homes. So all these environments actually require different technologies so sensor networks can be composed of sensor devices, which are as simple as Battery operated Embedded systems like you can think about arm cortex based Computing devices with some physical onboard sensors. They have a battery attached to it and a radio interface So these are connected to a Centralized system like an application with with a connected database Which is offering subscription to different end users The database is actually the short-term and Storage and long-term arch archival for retrieval for data analysis like Big data or deep data The sensor networks have been there for quite some time but the ubiquitous sensor network services as in NGN architecture have evolved into something very Unique because since NGN in itself is a highly converged network So USN services are also Converging very fast because so many different network types and Users can be provisioned these services in order to provide custom-made more Personalized services some new concepts like context awareness and situational situationally aware services can be provided which require minimum change in Their provisioning if the circumstances or the situation is the same for a variety of users or if a user is so So sensitive or particular about using services in certain contexts differently than these can be provisioned this requires a complete network of Information infrastructure that is a lot of information is coming from these sensors And their whole network is generating tons of information. Now this information has to be digested Through an infrastructure. So this infrastructure requires a lot of servers, etc There are certain Restrictions in terms of user of sensor networks because they could be non IP based these could be proprietary or localized But once we talk about USN, it means global users sitting anywhere in the world can have access which could be individuals or Enterprises governments, etc. And the applications are just starting to evolve Like military applications health care transportation, etc Now let's look at the overall architecture how USN services can be provisioned We look at the physical architecture, which is the lowest layer of sensor network here We have different kinds of sensors like RFID, which is a basically passive tag that responds to a reader so it can be used for a variety of Inventory tracking management supply chain applications, then we have a vehicular ad hoc networks Mounted sensors known as vehicle sensor networks. Sometimes these are known as Manit's mobile ad hoc networks in vehicles known as vehicular ad hoc network Then we have the access network, which is any broadband technology which could provide connectivity between the service provider to the NGN So we have the engine architecture Following and then we have the user side which starts to appear starting from the middleware Because the middleware is actually that information architecture comprising the management services location management services context services Then directory services, etc to mention a few so these middleware Services actually make sure minimum information is sieved or is passed to the end user without swarming it or flooding it with unnecessary data So then we have the user applications on the top, which is certainly the application layer We have applications in military Logistics supply chain health Machine condition monitoring. It's a very latest field in industry 4.0, etc So it means that ubiquitous sensor network services are going to be something Interesting that we'll see in years to come inshallah