in the Internet The wide area network established by Internet VPN also has the disadvantage of being difficult to set up, monitor and troubleshoot. Internet connection, there is no way to ask for help when the problem occurs, the service provider only belongs to the "Best effort" transmission, and can not guarantee the transmission in the shortest path.
Many companies rent a number of wide-area connections as a diversion and backup. The key applications rely on MPLS transmission; the secondary ones are supported by broadband. These circuits operate independently and cannot support each other. It is only hand-over when it happens, and it takes time and wreck. In recent years, the quality of broadband has improved. Many companies have adopted broadband more easily, and multiple VPNs support each other. However, the Internet has always been unstable; especially for transmitting multimedia, Loss Packet or Jitter is more common; VoIP or video is abnormal, and managers spend a lot of time debugging, which is not worth the candle.
As can be seen from the above, the configuration and management of the WAN is complicated, and a large number of IP-Sec VPNs are sometimes difficult to manage and fault tolerant. SD-WAN targets the above-mentioned congenital defects, and uses the application as the setting center. It can share multiple different lines (MPLS, broadband) and fully configure VPN and routing. In addition to the appropriate resources according to the requirements and characteristics of the application, Instantly know the performance of the line and automatically use the best connection method.
In the past two years, there have been more and more solutions to solve WAN connections with SD-WAN. The more widely used Viptela and CloudGenix, the Riverbed and Silver Peak, which started with wide-area optimization, are also catching up and developing SD-WAN functions. However, SD-WAN continues to evolve, in addition to improving WAN deployment, reducing the cost of unified communications, improving the SaaS user experience, and reducing deployment staff. Velocloud has just acquired Cisco's stake in SD-WAN vendors and has recently won several industry awards. Velocloud combines cloud technology with support for unified communications, and SD-WAN functionality is a big step forward.