Technology
Overview
Advanced Traffic Management
There are two major problems with IP networks today that are critical to improve:
- Major overloads due to "super-users" who consume an unfair portion of a shared capacity
- Serious quality of experience (QoE) problems for voice, video, and response times
Controlling "Super Users"
Today Deep Packet Inspection (DPI) is often used to attack the overload problem. DPI attempts to recognize all the applications by their protocol and then allows the customer to adjust the priority for each application. Although this can work, it is expensive and requires continued maintenance to detect and prioritize all applications. However the problem is much simpler. It stems from an old problem; the Internet tends to provide equal capacity per flow so that when an application uses 30 flows, it receives 30 times the capacity of the average user with one flow. The original multi-flow application was P2P but today many applications like online mapping use multiple flows to speed up the display. This creates major inequities between users in terms of the capacity they receive compared to what they pay.
Identifying all the applications with DPI and adjusting the priority for each is a very hard way to solve this problem. Instead, Anagran monitors all the traffic and flows per subscriber and then adjusts the priority (and thus rate) of the multi-flow applications to equalize the capacity per subscriber in each payment class. Since there is no need to dig deeply into each packet to identify the application, Anagran can stream the packets through its systems at 10Gbps wire speed with virtually no delay. Anagran's unique flow rate control capability allows the priorities to be applied in real time in its FPGA hardware path without the intensive processing and maintenance undertaken by DPI systems. The end result is not only much less expensive but far more effective since the priorities adjust automatically in real time.
Quality of Experience and Improved Throughput
At the same time that an Anagran system is managing subscriber equalization (if desired), it is also dramatically improving the QoE for the subscribers. This is something that neither DPI nor Wan Optimization systems can accomplish. TCP, the majority application on the Internet, is seriously hurt when it passes through a bottleneck where packets are delayed and/or discarded with queuing techniques. Since each TCP flow keeps increasing its rate until one or more packets are lost, it is normal that every TCP flow is rate-controlled at one or both edges of the network. Queues add delay and discard random packets which widely spread the flow rates whereas Anagran's unique Flow Rate Control (FRC) watches the rate of each flow and discards carefully to ensure the rate desired without adding delay. Voice and video are detected and are not subject to discard. The result is a major improvement in response time, voice quality, and video quality. Typically, web access time is reduced to 1/3 of what it would have been and voice and video are delivered with high quality even on a heavily loaded link. Also, delay jitter is eliminated since all delay jitter is introduced by queuing, not distance. As a result the load on a wireless base station, DSLAM, or cable channel load peak can be allowed triple the old peak and still deliver the quality response time, voice and video. Maintaining QoE over much higher load factors will usually provide far better throughput improvement than the typical WAN Optimization systems and since the Anagran system can accomplish this for many channels at one end of a link instead of pairs on each link, the cost improvement can be very significant.