5G has been a popular topic this year. Many articles about 5G are emerging, discussing topics from national strategies to protocol fields. 5G+ has become an inevitable topic in many articles. As a Technical Engineer from the infrastructure department, I frequently join the 5G discussion. I will discuss 5G through a series of questions to help understand it from a different perspective.
Q1: Why are we talking about 5G again?
A: Before 5G became a popular topic, I was asked this question the most each time I talked about 5G. The concept of 5G you are thinking of is not the 5G I am discussing. What you mean is 5 GHz used in Wi-Fi, and what I talk about is the fifth-generation mobile networks. Currently, household wireless routers mainly use 2.4 GHz and 5 GHz frequency bands. The routers using 5 GHz operate much faster than those using 2.4 GHz. The 5 GHz routers are frequently mentioned as 5G routers, which are confused with the fifth-generation mobile networks. It is easy to answer this question, but when we discuss more, a new question arises: What is the relationship between 5G and Wi-Fi? You may have heard of Wi-Fi 6. Since the number 6 in “Wi-Fi 6” is higher than the number 5 in “5G,” which one is superior? To put it simply, they are used in different scenarios, so neither is superior to the other. In the 4G era, Wi-Fi was not phased out. In the 5G era, Wi-Fi will not be phased out either. I will discuss the differences between Wi-Fi, 3G, 4G, and 5G in future articles.
Q2: How soon will 5G be ready?
A: I’m not sure about the specific time, but it will be earlier than previous forecasts. The progress in 2019 had been expected to be achieved in 2020. Traditional technologies have developed from a business-driven phase to a commercial-driven phase. Compared with them, 5G has an extra policy-driven phase. Firstly, licenses have been issued, including the China Broadcasting Network. Although 5G construction has been permitted regarding policies, a specific frequency has not been defined. Secondly, network construction takes time. 5G is allocated a high-frequency band, so coverage is a problem. To achieve the same coverage as 4G cell towers, the number of 5G cell towers must be increased several times over. Telecom operators have started construction at hot spots. In 2019, the three major telecom operators in China planned to build 100,000 cell towers in 4 municipalities and 27 provincial capitals. However, it will take many years to reach the level of 4G coverage. Thirdly, standards are important in the field of mobile communication since 5G will be applied all over the world. The 3rd Generation Partnership Project (3GPP) has already formulated the 3GPP TR 25.996, but it is predicted that the standard will come to its R16 freeze phase in the middle of 2021. At that time, the requirements of the 5G vision in China can be met. Of course, the demand for high bandwidth has been supported by the current specifications.
Q3: Can I use 5G phones now?
A: Yes, but it depends on how much you’re willing to spend. Xiaomi 5G phones have been released and priced less than CNY 4000, but ask yourself, Can I afford a new one in half a year? 5G can be built in a non-standalone (NSA) or standalone (SA) architecture. The two concepts are distinguished by whether end-to-end communication from a wireless network to a core network is enabled. The advantages of 5G can only be fully-leveraged in the SA architecture. Though driven by policies, the three major telecom operators have adopted the less-costly NSA architecture. According to China Mobile’s device specifications, 5G phones only supported in NSA architecture will not be admitted to networks soon. Currently, only Huawei phones support NSA and SA architectures. For consumers, features, such as ultra-low latency and millions of connections, are not required currently. For the feature of high bandwidth support, NSA-powered phones are not much different from SA-powered phones. Also, many cities have released 5G deployment maps. Before you buy 5G phones, check whether your regular activity scope is within 5G coverage. By the way, the three major telecom operators announced the number of reservations for 5G data plans, totaling tens of millions. This reflects users’ enthusiasm for 5G without considering the actual number of 5G users.
Q4: Why does 5G excite all walks of life?
A: 5G promotion is motivated by the common benefits of telecom operators and device manufacturers, but there is still uncertainty. 5G is a type of infrastructure for connections. Its target is broadened from consumers to everything electronic. This change suffices to cheer up the entire industry. Imagine a world where everything electronic is connected. With the promise of tenfold improvement in network capabilities and the emergence of a concept similar to service level agreement (SLA), this technology becomes desirable to a range of industries that have access requirements. If the access problem is solved, industry reconstruction becomes possible. Connect all computing and storage devices that can be connected. Ren Zhengfei, the President of Huawei, explained the importance of 5G to the US, saying”The US needs 5G to reduce their costs on optical access.” The Fixed Wireless Access (FWA) mode may not apply to China. China has been replacing copper wire transmission with optical fibers for a long time. If the set top boxes (STBs) are replaced with 5G devices, making the 5G devices the hub of household devices, China Broadcasting Network may come to a new development phase. The government and enterprise departments of the telecom operators have been focusing on fixed network access for their enterprise customers. In the future, they will shift energy to a more reliable, safer, and faster 5G access that provides a larger capacity.
Q5: How fast can 5G access be?
A: We are often told 5G latency is shortened to 1 ms. News about telesurgery, unmanned driving, and other remote operations have proven low latency claims. It is important to note that the 1 ms latency is defined for the air interface. This is the latency between cell towers and 5G phones, not an end-to-end latency. In telesurgery across two cities, the transmission latency is subject to the physical property of optical fibers, and not affected by the access technology used. In this case, the latency in the section of transmission from the operating room to the cell tower that serves the operating room can be shortened. Regarding the air interface, the 1 ms latency cannot be guaranteed as well. A communication network similar to a software-defined network (SDN) involves the control plane, user plane, and status of different protocols. Generally, device operations may involve both protocol status switching and control plane priority. These processes take time. The 1 ms latency is probable in an ideal scene where pure data is sent with everything prepared. Also, the protocol and business process optimizations we have for 4G networks are inevitable in 5G. We will have new processes to optimize in 5G. Now that latency can be shortened in the last section of transmission, how do we use the optimization to the greatest extent?
Q6: What is the relationship between 5G and edge computing?
A: Edge computing was not born out of 5G. This concept emerged a long time ago. Content Delivery Network (CDN) is a form of edge computing. Later, the concept was introduced in mobile networks, and a new term, mobile edge computing (MEC), came up. After that, the European Telecommunications Standards Institute (ETSI) created a new term, multi-access edge computing (MEC), based on edge computing. This new term broadens the applicable scope of the original concept. The best solution to minimize the end-to-end latency we mentioned previously is deploying computing close to a cell tower. 5G architecture was reconstructed to implement the design. The user plane is separated from the control plane to make edge computing possible. User port function (UPF) devices are deployed to provide network element support for edge computing.
Edge computing gives telecom operators a chance to create new opportunities. They developed edge cloud computing and storage to provide access on the edge. The design sounds simple, but many aspects must be considered and verified, for example, the definition of the edge, the scale of an edge computing room, design of the architecture, management, and difference with a CDN.
Q7: What is slicing?
A: With a variety of differentiated network requirements, a unified network is not applicable. Network slicing allows telecom operators to divide a network into multiple virtual end-to-end networks on a unified infrastructure. Each network slice is logically independent of the wireless access network, bearer network, and core network to adapt to various types of applications. The design is compared to a multi-lane highway where various vehicles run in different lanes and do not affect each other. It can be compared to a reversible lane where traffic can be directed. The “dumb pipe” has become an operational and differentiated pipe. The pipe finds its value and provides a technical basis for businesses to make SLA commitments. However, many questions are still not answered. For example, how is this lane defined? What requirements can this on-demand lane meet? What is the path of capability calls? The value of the pipe will be leveraged better in 5G, but how to use this pipe is a great challenge and opportunity for our businesses.
Q8: How will 5G influence the current businesses of Alibaba Cloud?
A: OK, let’s talk about how 5G will influence the current businesses of Alibaba Cloud. New businesses that may be derived from 5G will be discussed later. I came across some news saying that certain applications successfully ran on some brand of 5G phones or under a 5G network, and the success deserved celebration. Did it mean that 5G was used? I don’t think so. When we built an all-in wireless network, we didn’t simply migrate webpages from a PC to a phone screen or resize images for a simple device adaption. Instead, we upgraded and reconstructed the businesses on PCs based on the characteristics of wireless networks and devices to improve user experience. Let’s review the characteristics of 5G. “Edge” is created between devices and the cloud. The first challenge is how to make good use of this resource. Serving targets are shifted from users to things. They can be targets with ultra-high hash rates or ultra-simple targets. The second challenge is how to serve these targets and make good use of them. The edge makes distribution possible. The traditional north-south traffic structure may change to an east-west traffic structure. The third challenge is how to direct or adapt businesses to this traffic structure. The 5G infrastructure pipes may demonstrate more network capabilities. The fourth challenge is how to use these capabilities to create value, as we use APIs of an OS. These are a few characteristics of 5G.
Q9: What new services will emerge from 5G?
A: This question was asked the most when I had this discussion with my colleagues or customers. Despite the discussions, I cannot give a definite answer, but I will tell two stories. In the development phase of Enhanced Data rates for GSM Evolution (EDGE), I joined the first Push to Talk (PTT) program in China. The PTT is an intercom based on mobile networks. At that time, Nokia developed a PTT phone with the PTT button. With this feature, the phone could be used as an intercom for group chats or private chats without any software support. Users could dial a number to place a voice call. The call was charged based on the data used. Except for the full-duplex mode, the phone was ideal. The feature was similar to the voice chat feature of WeChat. WeChat was popularized later, but PTT was phased out. During the promotion and construction phase of 3G, the video call was the most important application, and the front-facing camera was also a standard configuration. During resource planning and configuration, a special voice channel was reserved to ensure the quality of video calls. After 3G was put into commercial use, few users used the video call feature. This application became a decoration. Apps like FaceTime and WeChat helped popularize video calls later. Now, telecom operators are constructing Voice over Long-Term Evolution (VoLTE). Let’s see how it will develop. During the development phase of 5G, there may be more stories like that happening.
Q10: Will Alibaba Cloud join in 5G?
A: This question is a bit sensitive, but I will still talk a little bit about it. I believe 5G will create a win-win era, but no one can win it all. Our business modes and cooperation modes will be changed. The service-based architecture (SBA) is critical to the core network used by 5G. This architecture is developed by China Mobile and is very similar to the microservice used in the IT field. Can our technical experience in this field be applied to communications? A distributed cloud is different from a centralized public cloud. Can we use our software and hardware capabilities of the basic cloud to compensate for our lacking knowledge of edge cloud? Network elements on a 5G network can be decoupled. Can our advantages in the forwarding field be used? The next competition between Internet enterprises will focus on B2B, G2B, and the Internet of Things (IoT). Our cooperation mode may be changed to frequency sharing to extend our businesses to access 5G. Alibaba Cloud will not develop itself into a telecom operator. With the discussions, I hope we can be more creative in infrastructure.
With the development of 5G, more questions will arise. While thinking of the new questions, we must also practice.