The wireless mesh network comes from the self-organizing network of the military network. As its civil application, its characteristics have attracted the attention of all walks of life. In particular, the bearer of voip in wireless mesh networks has been regarded as a unsatisfactory service application in recent years.
With the rapid development of various wireless data networks, the market has already put forward demanding requirements for various technologies. Only technologies that meet user needs can survive well. The Mobile Self-Organizing Network (MANET) originating in the military field has received crazy attention from various research organizations since the end of the last century, because it is easy to deploy, self-managed, and does not rely on infrastructure and other features to meet the needs of disaster and field scenarios, however, due to its performance and cost disadvantages, it has not been widely used in civil facilities.
To improve MANET's applicability to civil networks, Wireless Mesh networks have been proposed in recent years, the core idea is to physically separate the peer nodes that act as routers and hosts in the traditional MANET into a wireless mesh router node and a wireless mesh client) and connect the wireless mesh router to the Internet through the border gateway.
The Wireless Mesh Network inherits the advantages of MANET self-organization and has the advantages of high bandwidth, low cost, reliability, and scalability. Because a wireless mesh router is a fixed device and cannot be moved easily after deployment, the cost of the network adapter that supports mobile MANET is relatively low. As we all know, the bandwidth and distance of wireless transmission are inversely proportional, therefore, a low-cost wireless mesh router can effectively increase the transmission bandwidth. Second, because the wireless mesh router is a network connection, failure of a link does not affect transmission. Such a network has a high degree of reliability.
Thirdly, because the wireless mesh network inherits the self-management features of the Mobile Self-Organizing Network, the expanded wireless router can be configured automatically, so it is highly scalable. Finally, the wireless mesh network meets the Internet access requirements that are indispensable for any civil facilities and is more practical than MANET.
Due to this advantage, wireless mesh networks have become the focus of research institutions, and their support for upper-layer applications is focused on mobile voice services, however, the performance evaluation results of traditional MANET for VOIP services are always unsatisfactory. Here, people are very concerned about whether the wireless mesh network can meet the quality requirements of users for real-time voice services.
Iometrix, a professional testing company, conducted the first performance evaluation and testing of Wireless Mesh Networks Based on the draft study by the IEEE 802.11 Working Group. This test compares the two most popular wireless Mesh Network Solutions: single-radio wireless backhaul) solution and multi-radio outdoor mesh solution.
This test evaluates the average Opinion score (Mean Opinion Socore, MOS, it is an evaluation indicator for the user's subjective voice quality experience stipulated by the telecommunications industry standards ). This test also evaluates the performance of switching latency in user roaming scenarios.
The final test data is effectively analyzed and extracted to characterize the system features related to wireless mesh VOIP applications. In the following chapter, we analyze the performance characteristics of the VOIP Application carried by the Wireless Mesh Network Based on the test results.