Do you know the new nouns that are endlessly related to the "net" in the Internet of Things?

5G, LPWAN, SDN, NFV, TSN... These new and nouns are related to the "net" in the Internet of Things. Do you know anything about them? Can you name them all? Do you know what they mean?

In order to restore the "simplification" and "beauty" of communication technology, in this article, I try to use the most easy-to-understand language, so that you do not need a lot of CT (communication technology) and IT (information technology) knowledge. Also understand the meaning of these technologies. From "Looking at the layman" to "seeing the doorway" is the beginning of this article.

A metaphor for connecting various hot words in the field of communication

Do not say much, go to the topic. In order to more intuitively reflect the relationship and comparison of the latest communication technologies, I will take the process of mailing express parcels as an example.

Although the core requirement of the end user is to send the various packages to the destination, after selecting a courier company, the user does not care what kind of transportation the company uses, the shipping method of the sea, land and air, the courier is Which kind of hybrids in China, Japan and Korea... These details, but there are price differences between different courier companies, service levels are different, users need to understand the basic express process, such as "power consumption", "bandwidth", "reliability", "Cost", etc., to achieve a lot of express delivery expenses.

The process of transferring data between different devices by various communication technologies is exactly the same as the process of delivering parcels by courier companies, and each of them performs their division of labor and cooperation. Here, if the data is likened to goods, the communication network is likened to the road, and the network message carrying the data is like a delivery vehicle, then the story begins:

1. Start with the "entry" of express delivery, NB-IoT, TSN, Zigbee, WiFi, etc. These communication protocols are designed for IoT applications, just like various express trucks, how to solve various terminal devices. The data package is delivered to the nearest sorting station.

For example, NB-IoT (narrow-band Internet of Things) is a long-distance truck. The cargo boxes of each vehicle are small. Although there are not many packages at a time, they are extremely fuel-efficient and have low transportation costs.

Vehicles such as TSN (Time Sensitive Network) are designed to deliver time-sensitive, real-time delivery packages in the smart and smart cars. In order to solve the problem of real-time, TSN has customized a special express model, just like the flying car of the second-generation rocket in the movie "Black Man", to ensure the speed and timeliness of the delivery vehicle.

2. In the process of picking up the goods, when encountering large data volume and data parcels with high transmission speed requirements, ordinary express trucks are not enough. At this time, wired standard Ethernet, 3G/4G, and 5G are required. The corresponding broadband communication technology debuted. The vehicles they provide are ships, trains and airplanes with long transmission distances, large cargo loads and high quality of service.

At this time, NFV (network function virtualization) is needed, which optimizes the road itself and solves the problem of road carrying flexibility without changing the original infrastructure. When there is a special express demand, NFV can quickly build a virtual road. When the vehicle passes, the virtual road is cancelled and the relevant resources are released back to the resource pool. NFV can also create virtual police, making it difficult for robbers to get started.

Seeing this, I believe that you have a general understanding of what kind of problems each technology solves in the entire vertical information transmission process. Next, I will focus on the core trends, including 5G, software-defined networks and real-time Internet of Things, grouping relevant key technologies and talking about their respective missions horizontally.

5G supported by wide, narrow, fast and slow

The common people's impression of 5G is that it is 10 to 100 times faster than the existing 4G, but 5G brings more than just the speed of the network, there are a lot of technical terms, including uRLLC, eMBB, mMTC, etc. and the evolution to 5G. There are dozens of NB-IoT, eMTC, LTE-V, etc., which makes people feel clouded and difficult to understand.

In fact, for users, what is more important than the speed of the network is the improvement of 5G's network capabilities. It will be able to carry more kinds of IoT devices for various communication scenarios. In order to solve this problem, it is obviously different from 4G. 5G uses innovative thinking and can support both “high polarization” and narrow bandwidth, low latency and high latency. It can be said that it can be wide and narrow. Can respond to terminal needs quickly and slowly.

The narrowband branch of 5G evolved from the popular eMTC (Enhanced Machine-to-Machine Communication) and NB-loT (Narrowband Internet of Things) in the field of Internet of Things. The Cat M/Cat NB in ​​the figure is its evolving path. In the future, it will achieve a million-level terminal access per square kilometer and an ultra-low power, ultra-low cost mMTC scenario. One of the core functions of these low-power wide-area network LPWAN representative technologies is the transmission of the perceived data of the "object", and the transmitted data basically has the characteristics of "small packet, low frequency". These small batches of data are needed by the user's direct business, which can be said to be a direct click on the user's business pain points. Of course, this narrow-band branch generally does not carry critical high-reliability services, and can undertake a large number of communication tasks that do not require real-time and sensitivity, and is supported as a 5G "slow" scenario.

Don't look at so many scenes, 5G can carry a variety of "polarization" scenes on a network, which is wide, narrow, fast and slow. It can be said that it is a brand new change.

Software-defined network based on soft and hard "decoupling"

SDN (software-defined network) and NFV (network virtualization) are undoubtedly the hottest trends in the IT field. At the MWC show in Barcelona, ​​which was just completed not long ago, almost all CT and IT vendors have adopted SDN and NFV as strategic directions for reducing communication costs, and proposed targeted products and solutions.

Maybe this set of words makes you feel a bit strange. If you explore the inherent logic of SDN and NFV, it is actually very simple, the core thinking is "separation" and "decoupling". SDN separates the control plane (which can be simply understood as the vehicle scheduling in the above example) and the data plane (the traffic flow on the road in the example). The NFV separates the software and hardware used in the network, and the decoupling is maximized. effect.

The main driving force for the development of SDN and NFV comes from data centers and wide-area WANs, but their existence can be used for reference and use in the Internet of Things. SDN and NFV address the need for business agility and agility in the Internet of Things. In the face of faster and faster communication technology, it is unrealistic to keep updating hardware and infrastructure to keep up with the times. Therefore, it is necessary to let control and software work to meet ever-changing business needs, speed up deployment time and improve network. The transmission efficiency, while ensuring that the hardware input costs will not increase significantly.

These software-based networking technologies, including SDN, NFV and SD-WAN, provide a new tool for flexible design of network architectures that can be tailored to the business needs of the Internet of Things. SDN is mainly to optimize the network infrastructure, such as switches, routers, wireless networks. NFV is primarily about the flexibility and low cost of providing value-added features, including load balancing, security, and wide-area optimization. The centralized management control function provided by SDN and the virtualization of the service functions provided by NFV can coordinate and control various data flows and service flows in the distributed IoT system.

With the advancement of distributed computing and terminal intelligence, SDN and NFV are gradually moving toward the edge of the network, advancing the development of edge computing, and the opportunities for IoT people to "go to me" in the future.

More important than SDN and NFV is the “decoupled” mindset behind them. This thinking has spawned various SDXs, and the synergy between hardware and software has taken a new height.

The earliest SDX appeared in the radio field. The device function is mainly determined by hardware. One device corresponds to a kind of dedicated hardware, which is not only inflexible, but also has poor cost performance. With the increase in hardware versatility and software diversity, people can give the same device multiple functions and even new features like never before, simply by changing the software.

Now this kind of thinking has gradually expanded to other fields, and there have been "software-defined storage", "software-defined network", "software-defined security", "software-defined data center"... Someone simply said "software defines everything", that is, SDX . Among them, the big one is the iPhone, and the same mobile phone hardware realizes multiple functions such as game machine, walkman and translation pen through personalized APP software. Soft PLC (Industrial Programmable Controller) in the industrial field is also one of the fruits of this thinking.

TSN and OPC-UA to break through industrial communication barriers

The last set of technologies comes from the industrial sector, TSN (Time Sensitive Network) and OPC-UA ("Dialog" protocol between devices). Together, they solve the problem of the uncertainty of standard Ethernet in industrial applications, and the problem of difficult communication between industrial communication and language.

The essence of standard Ethernet is a non-deterministic network, but in the industrial field must require certainty, a set of data packages must arrive at the destination in a complete, real-time, and deterministic manner. In order to meet this demand, TSN self-developed "flight express trucks". Ordinary trucks from Beijing's international trade to Tiananmen Square, the whole journey of 5 kilometers, about 20 minutes or so, the peak period of work will be longer. The TSN flying car allows the delivery plan to be scored in seconds. If you drive at 100 km/h, the TSN truck will arrive at Tiananmen Square on time after 3 minutes and 0 seconds, eliminating the standard "congestion" caused by traffic. Non-deterministic.

In addition to addressing Ethernet determinism, TSN is also addressing fragmentation issues in the industrial arena. Be aware that there are complex, sloppy Ethernet protocols, such as Ethernet/IP, Profinet, Modbus TCP, EtherCAT, PowerLink, SERCOS III, etc. Different manufacturers are supporting the camp, and no one can dominate the rivers and lakes. Fragmentation of industrial communications has also led to a disparity in the description of data parcels. Even if a parcel is received, it is in vain to read the contents.

So the core idea of ​​TSN and OPC-UA is to propose an interoperable system that supports multiple manufacturers, protocols, and organizations to share on the same network, while data is parsed in the same language, not only, but also Available. As a low-level general architecture, TSN enables more companies to integrate OT and IT on this architecture. This convergence enhances the connectivity and versatility of industrial equipment and provides a faster and better development path for big data analytics, edge intelligence, and new services for the future.