Talking about the usage scenarios of HoloWAN

1. HoloWAN is applied in the field of satellite communication

1.1 Background and challenges in the field of satellite communications

In recent years, the amount of Internet protocol data transmission on satellite networks has continued to surge, and now satellite communications have been widely used by tens of thousands of organizations around the world for voice, video, and a series of important data transmissions.

As a kind of signal propagation between space vehicles and complex atmospheric environment, satellite communication will have a long delay and a large amount of data loss. These factors will affect audio and video communication, logistics support system, emergency The performance of key applications such as service dispatching systems and military command systems has a significant impact. Therefore, before the satellite communication application is delivered to the end user, it is the responsibility to predict what problems the application will face as early as possible to ensure the user experience.

1.2 Using HoloWAN to Realize Satellite Network Simulation

As the growth of satellite communications accelerates, organizations around the world are turning to network emulators for pre-deployment testing to ensure quality of service to end users. Among them, the HoloWAN product is used to test the adaptability of the satellite communication system based on the IP communication protocol.

Benefits of using HoloWAN:

 1、降低开发后期重写应⽤程序的相关成本；
 2、⼀次性确保最终的交付质量；
 3、通过在虚拟化环境中重现卫星⽹络环境进⾏准确的故障排除，降低解决问题的成本。

The role of HoloWAN:

1、可以准确地创建上⾏链路/下⾏链路传输的⾼延迟，可以模拟恶劣天⽓和信号衰减对卫星通讯的影响，然后可以在实验室环境中解决以前最终⽤户在⽣产环境中运⾏关键业务遇到的问题。
2、可以跟OPNET等⽹络仿真软件搭配⼯作，由OPNET等仿真软件模拟计算出延迟、丢包等参数，然后通过⽹络仿真仪进⾏环境模拟。

2. Application of HoloWAN in online games

2.1 Background and challenges of online games

Gaming is a major online activity for cash, and gaming applications need to be able to handle a variety of network conditions well with a variety of different Internet service providers, which is key to player experience and game success. A bad gaming experience caused by network issues can have serious consequences.

The biggest challenge facing online games is data delay and data loss. These two important factors will make the game feel "stuck".
The reasons for these two problems are:

1、如果⼀台机器的帧速率下降（或低于其他机器），其他机器将处理它们的命令，渲染所有分配的时间，最后等待下⼀轮。
2、由于互联⽹延迟和数据包丢失造成的通信延迟也会导致游戏卡顿
3、另⼀个影响游戏可玩性的问题是通过互联⽹传输的数据速率。有很多因素会影响数据速率，包括其他玩家的位置、地形布局、任何作战情况、游戏中对象的当前状态等。数据速率越⾼，玩家越可能遇到数据延迟或数据丢失。

2.2 Using HoloWAN to simulate a real network environment

HoloWAN supports the capture of network environment on terminals such as Android phones and Windows PCs through the free software Recorder. Its capture time and frequency can reach 0.2 seconds per probe, and it supports recording up to 100,000 probe data. The Recorder software can export playback files for playback by HoloWAN, and HoloWAN will reproduce the real network environment according to the captured data. By capturing playback, testers can simulate scenes with harsh network environments such as subways, elevators, cars, passenger stations, and large-scale event sites to ensure the operability of the game on the Internet.

3. HoloWAN is applied to data center migration

3.1 Background and Challenges of Data Migration

Enterprises around the world are moving their application and data servers from centralized local servers to remote data centers, integrating resources from cloud service providers and outsourcing most of their IT infrastructure. These strategies provide significant benefits such as: significant reduction in IT costs, improved business continuity and information security, optimized service management, compliance with government and industry regulations, and more. Most enterprises are currently in the early stages of consolidating servers or performing major data center migrations.

While data migration brings benefits, it also faces many challenges. Data center migration has a large impact on application performance and service levels. Users who were previously local to the server supporting their business applications become remote users. Network latency can vary significantly when the physical location of a data center changes, because geographic distance can have a significant effect on network latency between clients and servers.

For example, a simple doubling of latency (because the server is now farther away from the user). In terms of latency, it might appear that the operation will take twice as long, but the added latency also reduces the throughput of the application, further affecting the end user.

3.2 Online performance test using HoloWAN

The online performance test simulates the final effect of server migration by deploying a HoloWAN emulator between real users and servers. HoloWAN emulators can provide slowly increasing latency and the ability to decrease bandwidth over a period of time. This can test in real time whether the user experience after data center migration can satisfy customers.

advantage:

 • 模拟真实的数据中⼼搬迁的网络环境
 • 能够模拟多个差异远程站点 （与不同类型的⽹络连接）
 • 显著降低成本
 • 不需要专业⼈员进⾏分析
 • 实时统计⽹络使⽤率
 • 发现问题可以⽴刻解决
 • 这是⼀个灵活的解决⽅案，您可以⽴即还原到原始未受损伤⽹络中

4. HoloWAN is used in the field of video streaming media

4.1 Background and Challenges in the Field of Video Streaming Media

Video sharing services, especially video streaming, have become increasingly popular over the past decade. Many users consume hours of video every day in the form of news, TV series, and movies. Additionally, a growing number of mobile applications are leveraging live video streams from smart devices such as baby monitors and home security systems.
Video accounted for 73% of Internet traffic in 2016, and according to a forecast released by Cisco, video will account for 82% of total Internet traffic in 2021.

As video sharing services become more important in the multimedia market, quality of service (QOS) and quality of experience (QOE) become the biggest barriers to effectively compete with broadcast TV. Users primarily stream video over Wi-Fi or cellular networks, but those videos can have quite different characteristics. Since the network is the most dynamic factor in online video streaming, it is imperative for video application providers to know how changing network conditions will affect the end user's viewing experience.
Internet video is based on packet transmission and can be subject to delays, transmission errors, data loss, and bandwidth limitations, which can have a devastating effect on the perceived quality of multimedia content.
Packet loss and excessive buffering are the most serious challenges to streaming video quality. When a packet is lost, the video player application stops receiving data until the lost packet is retransmitted, even though other packets continue to arrive. While the loss of a single packet does not necessarily cause the user to experience an error, problems can arise if a second packet is lost before the first lost packet is retransmitted. TCP's fast retransmissions and video players' buffers can recover from momentary delays in data transfers, but sustained packet loss for short periods of time can cause user-visible rebuffering events.

4.2 HoloWAN provides sophisticated testing solutions

With HoloWAN, engineers can emulate cellular, Wi-Fi, and IP networks, and simulate any combination of network impairments. Conduct network bandwidth testing to ensure the application is fully optimized to handle any service interruptions, while understanding how changing network conditions will affect the end user's streaming experience.

5. HoloWAN is applied in the field of real-time audio and video

5.1 Background and challenges of real-time audio and video

Real-time Internet, born for real-time interaction. The social interaction, entertainment, games, work, study, consultation, reading, shopping, commuting, sports, etc. that people complete on the Internet have all introduced multiple scenarios of real-time interaction. These scenes not only greatly enhance the interactive experience, some even have subversive effects. The explosion of real-time interactive scenes is reshaping the process and experience of the Internet. Real-time Internet is the main trend of the next generation of Internet.
The 5G era is approaching, and greater bandwidth means larger and faster data transmission. VR immersive video interaction, cloud game platform, smart terminal IoT, real-time application and transmission acceleration, remote driverless driving... Applications in the 5G era will be more "real-time", more "high-definition", and more "interactive". . 5G will bring a new round of eruption of RTC real-time audio and video application scenarios.

Caton, dropped calls, high delay, etc. These problems have always hindered the development of real-time audio and video calls. The fundamental reason for this is that the Internet was not originally designed for real-time communication.

People often compare the Internet to an "information highway", but a more accurate metaphor should be an "information highway network". The Internet is as intertwined and complex as the road network in reality. There are fast backbone networks like highways connecting two places, and bad network environments like difficult and rugged mountain roads. And transferring data over the Internet is like driving from one place to another. Internet transmission has three very important characteristics: delay, packet loss, and jitter.

The technical difficulties of doing a good job in real-time communication mainly include two major problems: intermediate transmission and terminal transmission:

1. Intermediate transmission refers to the backbone network data transmission process from router to router. Here, the data transmission services are mainly carried by channels such as optical fiber and coaxial cable. However, just like urban roads, once users increase and traffic increases sharply, data congestion will also occur in these data transmission channels. Therefore, delays and data packet loss are more prone to occur.
2. Terminal transmission mainly refers to
the transmission from Wi-Fi routers or telecom base stations to user terminals. If the user’s mobile phone has poor signal quality due to too far away or too many devices connected at the same time, real-time communication It will also be greatly affected. The above problems will cause problems such as freezing, blurring, and inaudible audio and video real-time calls.

5.2 Use HoloWAN for network emulation

In order to have a high-quality user experience when real-time audio and video products are launched on the market, product developers must simulate various possible weak network environments during development and testing, such as 2G, 3G, 4G, 5G, Wi-Fi, ADSL, Network conditions that may exist in various networks such as satellite networks. In particular, it is necessary to conduct rigorous tests on real-time network communication products for factors such as bandwidth, delay, packet loss, and jitter.

At present, real-time audio and video product providers such as Jinshan Cloud, Momo, Inke, Kuaishou, YY Voice, and Toutiao have used HoloWAN to simulate real network conditions in the laboratory. Robustness testing of products and other applications.

6. Application of HoloWAN in Military Services

6.1 Background and challenges of military service

For thousands of years, the transmission of network and information has played a vital role in military activities and affairs. With the rise of modern communication, the ways of information transmission to frontline troops have become more and more diverse. Previously, most military communications relied on radio. The systems used for information exchange and command are rapidly changing. Military services now aim to provide critical IP network services through wireless networks and satellite networks.

Satellite communication, as a way of signal transmission between space vehicles and complex atmospheric environments, experiences long delays and a large amount of data loss. These factors will affect audio and video communications, logistics support systems, emergency The performance of key applications such as service dispatching systems and military command systems has a significant impact.

Modern warfare is a highly complex environment that supports many users' mission-critical applications such as logistics supply, battlefield command, search and rescue, and more. These services depend on the system being able to provide instant and accurate information between any desired two locations, and the network system must be reliable enough to deal with any foreseeable situation. These systems must be rigorously tested by simulating precise network conditions before delivery.

6.2 Application of HoloWAN to Military Services

The HoloWAN network emulator can reproduce the radio network and satellite network environment used by military services, so the performance of the application can be rigorously tested to ensure quality before it is actually implemented.