Discussion on the unification of software and hardware standards for digital TV set-top boxes

Digital TV set-top boxes have experienced a long period of chaos due to the market fragmentation of radio and television and the lack of unified standards. Many radio and television operators have felt that this chaos has brought great difficulties to the after-sales service and function upgrades of set-top boxes. At the same time, they also feel that if set-top boxes cannot form market-oriented large-scale production with open standards, the digitalization of radio and television will always be based on set-top boxes. Two or three years after digitalization, many set-top boxes have passed the warranty period, and radio and television have to bear the heavy responsibility of after-sales service of set-top boxes. When many radio and television have not yet paid off the debts of old standard-definition set-top boxes, high-definition two-way has started rapidly. It is probably unrealistic to popularize high-definition TV by giving away high-definition set-top boxes. It is generally believed that the marketization and popularization of set-top boxes and digital all-in-one machines can help radio and television get rid of the burden of set-top boxes. However, the premise of marketization is that there must be open and transparent rules and unified standards to achieve true openness.

Some people believe that true openness must start with unified hardware, which is indeed a big proposition. To achieve the goal of completely unified hardware architecture, I don’t know how many chip manufacturers will have to close down. If the ideal of unified set-top box hardware is realized, it means that set-top boxes and all-in-one machines can be mass-produced and directly enter large supermarkets. The chip manufacturers should pay the most attention to this discussion, which will undoubtedly launch a revolution in the digital TV industry.

However, even the highly transparent PC industry has not achieved complete hardware unification, but only achieved standard unification and transparency. However, their rapid development experience can be used as a reference. There are several conditions for the high degree of unification of the PC industry. The core CPU instructions must be unified and compatible. In other words, the machine code of each software must be unified after compilation, and can be used directly without recompiling from the source code. The software interface is unified and transparent, and the BIOS interface for hardware is standardized and transparent, which can shield the diversity of the underlying hardware. The north and south bridges can use chips from different companies, as well as CPUs from different companies, so that there will be no exclusive monopoly at the hardware level, and even the CPU will have fierce competition.

Therefore, various operating systems competed on the transparent and open BIOS. Therefore, Microsoft was born in the fierce market competition after the unified and transparent standards of software and hardware under BIOS were established. Its competing operating systems include Mac OS Linux, etc. With Microsoft's operating system, a high degree of separation between software and hardware was achieved, and computer software and hardware competed fiercely on their own tracks, thus promoting the rapid development of the IT industry.

The opening of set-top box technology must also start with hardware. Currently, there are a wide variety of CPUs used in set-top box chips. To achieve the marketization of set-top boxes, the first thing to do is to unify the set-top box CPU.

Judging from the current CPU market situation, there are many companies providing reduced instruction set CPUs, and the competition is fierce. The more famous ones include ARM, MIPS, PowerPC, ARC, etc.

Because ARM is the most open, cost-effective, has the largest number of users, and is widely used, digital TV set-top box CPUs are showing signs of being unified with ARM CPUs. High speed and low power consumption are its major features. High-end mobile phone chips such as the iPhone use ARM1176. As the speed of set-top box chips increases, many set-top box chip manufacturers that do not have high-end CPUs have turned to ARM1176 CPUs, and even Cortex-A9 multi-core CPUs. Netbooks from many companies have also chosen ARM11. According to public information, the performance of Cortex-A9 has surpassed Intel's ATOM CPU.

PowerPC is a high-performance CPU with great scalability. It originated from IBM. All PowerPC instructions use 32-bit long instructions. It is produced by IBM and Motorola. The famous Apple G series Macintosh computers once all used PowerPC. This type of computer was used for image processing and other aspects that required a lot of calculations at the time. MIPS's 32-bit RISC CPU was also widely used in set-top box chips, and its feature is its strong floating-point computing ability. PowerPC and MIPS were also excellent CPUs, used in Nintendo, Microsoft Xbox game consoles, workstations and other occasions.

The ARC CPU is a configurable, cost-effective CPU that is widely used in standard-definition set-top boxes. However, according to Fujitsu's analysis, it lacks stamina in high-end CPUs.

ST, which takes the first place in set-top box chips, uses its own ST20 CPU for standard-definition chips. Although this CPU is a RISC architecture, it does not have equal-length instructions. When used in set-top box chips, it also consumes overhead for real-time decoder management. Although it is marked with a higher frequency, the actual speed is not very high. ST uses the ST40 CPU for high-definition set-top boxes. The basis of ST40 is SH4, which was developed by Hitachi. However, ST's high-definition chip CPU is also turning to ARM.

On September 25 this year, Intel launched the CE4100 for Internet TV, which attracted the attention of the broadcasting and television industry. Because it is the first IA-based digital TV chip, Internet TV is the opposite of broadcasting and television. Once popularized, in an open network environment, CA's CW sharing will make the encryption system of broadcasting and television useless, which is definitely a nightmare for broadcasting and television. But from the perspective of software engineers and the rich software sources, Intel IA-based CPUs are definitely the first choice.

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However, from the perspective of power consumption, everyone knows that the CPU of Intel PC is like a small electric stove. Heat dissipation alone is a problem. Even many netbook manufacturers that use low-power ATOM CPUs have failed because of the difficulty in solving the heat dissipation problem. Desktop computers have high requirements for power consumption, which makes Intel, which has been on this road for a long time, unable to adapt to the low-power set-top box field in a short period of time. People who have worked on single-chip microcomputers know that compared with reduced instructions (RISC), complex instructions (CISC) consume much more clock cycles per action than the latter, so under the same performance, CISC is inherently high-energy consuming. Intel can only reduce power consumption by increasing the operating frequency and improving chip technology. However, the emergence of ARM's Cortex-A9 multi-core CPU has made Intel's road to entering the digital TV market not smooth.

Embedded CPUs compete in an open market environment, and each CPU technology can advance rapidly in the competition. However, in terms of openness and cost-effectiveness, the above CPUs lag behind ARM and lack the support of third-party development tools, which puts them at a disadvantage in the competition. The actions of multiple set-top box chip companies to introduce ARM CPUs indicate that set-top box chips are tending to be unified towards ARM. ARM CPUs are likely to be unified in the field of high-definition set-top box chips, and will gradually transition from ARM11 to Cortex-A9, because ARM11 software can be directly used on Cortx-A9 in the future, so high-definition set-top box manufacturers that cut into ARM11 CPUs will benefit.

The stability of ARM11 in HD set-top boxes also seems to have been verified. Fujitsu went into mass production shortly after its first HD chip came out, which was beyond many people's expectations. This should be related to the selection of the mature and stable ARM11.

In the process of set-top box chips being unified into high-performance CPUs, as long as there is a transparent software interface standard, multiple CPUs can compete with ARM CPUs. If there is a CPU with higher performance than ARM in the future, it can be easily switched to it on an open platform. Therefore, the openness of software interfaces is crucial to the development of the industry.

If multiple set-top box chip companies can compete on high-end set-top box chips, operators can not only get high-quality and cost-effective HD set-top boxes, but also form an open competition environment, thus breaking the closed state of digital TV technology and forming a competitive situation of survival of the fittest. This is good news for cities that have not yet migrated and operators who plan to develop HD services, because HD interactive TV can develop rapidly in an open environment, which is worth looking forward to. Moreover, the current HD set-top boxes are all two-way, and most HDs are multi-decoding, which makes it meaningless to develop standard-definition two-way set-top boxes.

Unlike the era when IBM developed the PC, the performance of set-top box chips is far superior to that of PC CPUs of that era. However, the hardware architecture of today's set-top box chips is a highly integrated SOC. If the unification of the hardware architecture is initiated by broadcasting and television operators with higher technical levels, it should not be a problem. What remains is to unify the set-top box software platform.

Just like when IBM opened and unified the PC standard, Microsoft was born and Intel became successful. The birth of "Microsoft" and "Intel" in the digital TV industry should also be after the hardware architecture platform was opened and unified. What remains is the competition among various software platform manufacturers to compete for the throne of Microsoft in digital TV. Similar to the CPU market, this competition must be carried out in an open environment to be effective. In the current very closed digital TV industry, there can be no competition of survival of the fittest. However, the development history of the PC industry can provide a good reference for the digital TV field.

After the hardware unified platform is realized, the software platform (also known as operating system or middleware) running on the hardware can be separated. But there is a prerequisite, that is, there must be a BIOS interface layer similar to that of a PC, and the standard of this interface layer must be open and transparent, because the BIOS interface on the hardware CPU of a PC is open and transparent. After years of development, the BIOS provided by IBM at that time has long been replaced by a more advanced and efficient BIOS, but as long as there is an open BIOS layer interface, there will be competition for software above it.

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Similarly, set-top box chip companies should also separate their own software other than the hardware-related driver parts, and have the company that provides the BIOS package it, or package it according to the standard. However, according to the current industrial situation, the API function interface of the set-top box chip manufacturer can be understood as the BIOS on the PC, except that the set-top box manufacturer has not separated the operating system, which requires the set-top box chip company to make further openness. If the division of labor is clear like that of the PC, the operating system can be separated, thereby reducing the software development workload of the set-top box chip manufacturer, just like Intel, which does not make operating systems but focuses on chip design. On top of the BIOS without an operating system, there is a transparent and open interface, which can form effective competition and is conducive to the birth of "Microsoft" in the field of digital TV. For this reason, chip companies must have a greater degree of technical openness.

The reality is that set-top box chip companies not only provide BIOS, but also provide operating systems, or port some open source operating systems to their own chip systems. This is a relatively arduous and lengthy task that requires a long time to test and adapt to the market. The software platform expenses of set-top box chip companies are even greater than the investment costs of set-top box chips. The operating system developed by set-top box chip manufacturers at huge costs must of course be bundled with their own chip hardware. The expertise of set-top box chip manufacturers should be in chips. In order to promote their own chips, they have no choice but to "deviate from their main business" and get involved in the development of operating system software platforms, which takes a long time and also affects their main business of developing chips.

As for set-top box manufacturers, they usually have to run-in with the less mature software platform provided by chip manufacturers, and also conduct long tests and improvements according to different operators' users. This is also a costly and time-consuming process. Of course, the software developed by set-top box manufacturers must be bundled with their own hardware. The high cost of a new solution makes the cost reduction of introducing a new set-top box solution insufficient to make up for the development cost, so set-top box manufacturers are generally reluctant to change the set-top box solution, which in turn affects the entry of new high-performance set-top box chips into the market. PCs, which have much higher technical content and complexity than set-top boxes, generally only take a few months from sample to mass production of CPU chips, thanks to the high degree of separation of software and hardware. Due to the effective separation of software and hardware, many functions for new hardware can be developed quickly, while radio and television are difficult to upgrade due to the bundling of software and hardware, and many new functions cannot be loaded. Many networks are still the same as when they were just digitized. The new high-performance set-top box hardware is useless, and the subsequent attractiveness of digital TV has declined, which in turn affects the market demand for high-performance chips. Among all aspects of digital TV technology, the non-openness of CA has the greatest impact on the development of digital TV technology.

Due to historical reasons such as the framework of CA technology, digital TV software is naturally closed. The software developed by CA companies can only be safe under the protection of smart cards, which is itself a serious software and hardware bundling. Because it involves the particularity of CA security, it is necessary for set-top box chip companies and set-top box manufacturers to coordinate development with it. Originally, the development of set-top box software should be based on applications, but due to security factors, it is actually forced to directly or indirectly develop software around CA, and the importance of the set-top box main chip is ignored. The smart card software and hardware of various CA companies cannot be unified, which has caused serious confusion in digital TV standards.

The software platform of the set-top box chip manufacturer is bundled with its own chip, the application software of the set-top box manufacturer is bundled with its own set-top box, the CA software is bundled with the smart card, and the browser and stock software system also need to be bundled with the set-top box hardware. These hardware and software bundles for their own interests have made the digital TV standards extremely chaotic. Moreover, these standards are private, closed and opaque, and the information communication between them is mixed with complex technical and business factors. It takes a long time for an advanced set-top box solution to mature. This is the fundamental reason for the slow development of digital TV technology.

Some set-top box chip companies have realized this and have begun to separate the operating system and entrust professional system platform software companies to develop it to shorten the time it takes for chips to enter the market. For example, Fujitsu's docking with Taixin's open software platform is a very successful example. Fujitsu used the more open ARM11 CPU and docked with Taixin's open platform to quickly bring its chips to the market, so they also accelerated the plan for 65nm and 40nm set-top box chips.

Therefore, it is best for set-top box chip manufacturers not to involve the parts above the operating system, and concentrate on improving the performance and stability of their own chips. Look at Intel and AMD, they don't even make BIOS. It is recommended that if the country wants to formulate standards, it should start from the BIOS layer close to the chip, and not define it from the "middleware" layer with ever-changing concepts, which will cause unnecessary struggles between interest groups. If this layer is clearly defined, all chip manufacturers will have a unified standard and basis. If this is achieved, the magic of "Moore's Law" will be revealed in the field of digital TV. Above this transparent layer, companies that want to become the "Microsoft" of digital TV will have to show their true abilities and engage in fierce competition to achieve it. However, it is not enough to open up the BIOS layer alone, and the opening of the application layer API is also essential.

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Unfortunately, under the current circumstances, due to the technical level of radio and television operators, radio and television do not regard set-top box hardware as the most important foundation. From the radio and television digitalization process, it can be seen that many places first select front-end software such as CA, browser, and stock, and then choose the most important set-top box hardware. The main condition for selecting front-end software is to see how many set-top boxes have been transplanted and integrated with these software. The more set-top boxes that integrate and transplant corresponding front-end software, the more competitive the corresponding front-end software will be. Conversely, the more radio and television operators choose this front-end software, the more set-top box manufacturers will integrate and transplant corresponding CA and browsers. Radio and television follow suit like a group of sardines in the sea, being guided to swim in the same direction, unknowingly falling into the quagmire of set-top box chaos.

The biggest feature of software is that it can be continuously upgraded and new functions can be added. However, when it is used as a basic fixed standard, problems emerge. Almost all places that have started digitalization, once CA, browser and other software are determined, even after several years, the version number is still the same as at the beginning of digitalization. Even after encountering security risks such as CW sharing, CA cannot be upgraded and improved. This has forced people to reflect on the digitalization path that was taken by private front-end software instead of unified basic hardware. The core problem is that radio and television have adopted opaque private software and hardware standards, especially the strict confidentiality of CA interfaces. Because these software use a lot of black box technology, in order to ensure that these technologies are not exposed, these private software can only be integrated and transplanted, which objectively forms a bundle with set-top box hardware, which greatly restricts the progress and development of digital TV software, thus forming a decentralized and closed market for radio and television.

There are many set-top box chips on the market. It is unrealistic to unify the hardware in a short time. It is a beneficial attempt to unify the software interface first. It can solve the confusion of CA private standards, the confusion of stocks, browsers and other software, and also promote competition in the set-top box chip market. This unification of software and hardware must be open to the maximum extent, that is, the openness of the software platform should be as close to the bottom layer as possible, so that the upper-layer set-top box applications, CA, browsers, middleware and other software can have more choices, and the future technical path of radio and television will not be completely blocked due to technical closure.

But this will first have an impact on the security of existing encryption systems.

This is because the previous CA used a lot of black box technology, which relied on closed technology to obtain security. Once it is open, CA is no longer secure. This is a common problem faced by almost all CAs that need to be transplanted and integrated. CA was originally a software that can be updated and upgraded frequently, but under the protection of smart cards, it has become a firmware that is not easy to change. Generally, the CA version number after digitization remains basically unchanged, which makes the development of CA technology very slow. The security of CA is obtained by protecting CA software, CA keys, and algorithms through smart cards, and the security depends on the anti-cracking ability of smart cards. Since the security of CA depends on the anti-cracking ability of the chip, if the set-top box chip also has anti-cracking ability, the security of CA can be guaranteed. The downloadable cardless CA technology is developed on this basis. In this way, the security of CA depends entirely on the anti-cracking ability of the set-top box chip. From the perspective of cracking difficulty, the security of the set-top box chip is definitely higher than that of the smart card. Smart cards and card readers on set-top boxes belong to the hardware category. The absence of smart cards also reduces a source of hardware inconsistency. Since the security of CA relies on hardware protection and does not need to rely on algorithms and keys, the CA interface can be open. The opening of this interface can be close to the underlying layer. The open CA interface is conducive to the unification of CA standards. Each private CA software can perform its own functions on this interface. Even if CA has been deployed, the radio and television can still replace the adopted CA online, which will give CA competitive pressure and maintain the advancement of CA technology. The software version will not remain unchanged for many years after the deployment of CA.

Middleware and stock software also face the same problem. If the software interfaces close to the bottom layer are opened, it will be easy to form open standards, which will also bring about effective competition. Therefore, radio and television can have more flexible choices.

The principle discussed above is that the interface standards of software and hardware should be unified, and the software and hardware should be effectively separated, which is actually a reference to the successful experience of PC. Therefore, when choosing a digital platform, we should follow the principle of software and hardware separation and try to unify the standards, which is of great significance to the marketization of digital TV set-top boxes and all-in-one machines.