1) Unmanageable cost and user experience
All your users from different regions, for important events or regular shows have the same level of user experience, and your cost is also distributed evenly for paying or non-paying users.
2) Inferior user experience
Traditional CDNs are known notoriously for being cheap but bad user experience, including ages of waiting time to view the first video frame, and stuttering or blurring video.
Some important factors have impacts on costs and user experiences.
The network environment is complicated, and sometimes there is a big difference in network quality between two regions. Also, Routes might go across different networks. Furthermore, the performance of CDNs is not consistent and varies a lot.
There are tens of thousands of smartphone models, and the proportion of low-end smartphones is relatively high in some regions. The quality of the low-end smartphone has negative impacts on live streaming performance, such as slowness and stuttering in rendering, capturing, encoding, or decoding.
RTC network can ensure the quality of live streaming, however, its cost is too high for content distribution. High definitions bring better user experiences, however, they will lead to higher costs, stuttering, and pausing. It is a challenging issue to make appropriate cost allocations to revenue-generating sources.
ZEGOCLOUD SMOOTH Live resolves the problems with an efficient budgeting plan, and superior user experience for targeted users, regions, or events. For more information please refer to "ZEGOCLOUD SMOOTH Live, The Ultimate Live Streaming Solution".
But how do we resolve the problems technically? Let's talk about it thoroughly.
1. How to Allow Efficient Cost Management
1) Allows designating network resources to labeled user groups
The 20-80 rule applies in revenue generation too. 80% of revenue comes from 20% of users and regions. Users have become so bored with regular shows and will be more likely to be motivated to pay in ceremonies.
Therefore, VIP （Very Important Person）users, high ARPU (Annual Revenue Per User) regions and important ceremonies are used to ensure quality user experiences.
You can assign labels to various groups of users (including hosts). And SMOOTH Live allows you to designate different levels of network resources to labeled users at the individual level. For example, you are allowed to assign a quality nearby access server of the RTC network to a super-star host to guarantee service quality for her performance.
2) Allows managing 3-level networks to optimize cost structure
There are 3 levels of networks, i.e. CDN live, Standard Live, and Premium Live. The quality of Standard Live is better than that of CDN live, but CDN live is more economic in cost. The quality of Premium Live is the best among them, but Standard Live and CDN live are cheaper than Premium Live.
The CDN live is a select portfolio of regular CDNs, we have a systematic approach to trialing and selecting the best CDNs. Standard Live is a combination of regular CDNs and an RTC network, whenever even the best CDN cannot satisfy the service quality requirements, we will use the RTC network to guarantee user experience. Premium Live is essentially an RTC network designed for real-time interactions.
All these network resources are scheduled by a cluster of distributed scheduling centers that can schedule multiple CDNs and the RTC network, which is called the MSDN (Massive Serial Data Network) in aggregation. The solution allows you to make appropriate resource allocation configurations to balance cost and user experience.
You can allocate the RTC network to super start host and VIP paying users, assign select CDNs plus the RTC network to other paying users, and use regular CDNs to service the rest of the users. As a while, you can minimize the cost level but maximize user experience by optimizing the cost structure.
2. How to Upgrade User Experience
1) How to withstand fluctuating network impacts
Weak network conditions are the major culprits of inferior user experience.The Internet is a fairness-oriented and best-effort-delivery network, it is very common to encounter weak network conditions, such as packet losses and jittering.
The solution transmits data with a private UDP-based protocol that is connectionless and allows more leeways for redundancy and bandwidth control strategies. Once the receiver end reports packet losses and jitterings, the sender end can use the ARQ tactic to send the packets again, or the sender end can use the FEC tactic to send redundant data at the very beginning to avoid latencies.
The solution maintains an arrival queue as jitter butter at the receiver, and it monitors jitter volumes and packet losses and reports feedback to the sender end. The sender can analyze and predict network congestions. The sender will adjust the bit rate adaptively according to network conditions. For example, if it foresees network congestion, it will decrease the bit rate to maintain smoothness and usability.
The ARQ and FEC are common redundancy tactics, but they will increase bandwidth costs, and possibly enlarge latencies. And sending redundancy will aggravate network congestion too. We set a goal that we should keep redundancy less than 5%, and meanwhile maintain smoothness.
We use a lot of engineering tactics to achieve the goal. For example, once there is a packet loss, we will send the lost packet again; if the packet gets lost again, we will send an FEC packet to make sure that there is no more redundancy transmission.
2) How to implement video instant-opening and HD
We will continue to discuss how to achieve instant opening of the first video frame, and how to achieve high definition of live streaming video in the next series article, titled "How to Achieve Video Instant-Opening In The SMOOTH Live Streaming Solution". With improved features, user experience is upgraded to a next level.
3. Wrapping Up For Now
To achieve superior user experiences, we have not only deployed a global RTC-grade data transmission network and created a powerful UDP-based data transmission protocol, but also made various enhancements including instant opening, high definition, playback smoothness, etc.