|FAQ and Knowledgebase
|Q: Why are there two WAN ports on the devices?
A: With the help of two WAN ports Syswan devices are able to provide automatic failover as well as load balancing between the two connections. By using two low cost broadband connections it is possible to achieve higher reliability and better performance than with a single higher costing Internet connection.
Q: What is Automatic Failover?
A: Automatic Failover is a mechanism for detecting a failed link. Syswan devices have three different mechanisms, ICMP, HTTP and Traffic I/O.
Q: How does automatic failover work in Syswan devices?
A: Syswan devices utilize various techniques to determine whether the Internet connection is up or down. The primary method is using ICMP packets or "ping" to determine whether the device can talk to the ISP. Although under high traffic situations some of these pings may drop. Syswan devices anticipate this and if there is any sudden stop to incoming traffic the device will automatically begin determining if it is due to a failed link. If your Internet Service Provider does not support ICMP packets HTTP method is also available.
Q: How long does it take for Syswan devices to determine if a link has failed?
A: It takes anywhere between 1 to 60 seconds. While 60 seconds seems like a long time, it may only take this long if no computers using the device are trying to access the Internet, such as the middle of the night in an office building. During the day when there is frequent Internet usage the device will detect a failure as soon as 1 second.
Q: What is load balancing?
A: Load balancing is a mechanism for splitting traffic load between two WAN ports. It uses a mathematical calculation to figure out which WAN port is best suited for more traffic.
Q: How does load balancing work?
A: When surfing the web certain protocols are utilized, primarily TCP. Wheter many computers are surfing the web or just one computer is downloading a web page multiple TCP sessions are established, through advanced algorithms and many different calculations the Syswan devices are able to determine where to send the next TCP session, WAN1 or WAN2. By using this algorithm the devices are able to evenly distribute traffic load between both WAN ports.
Q: What about secure web sites and load balancing?
A: Secure web sites and load balancing have always been a concern but Syswan devices keep track and ensure full security. For example : if you establish a communication to a banking web site on WAN1 then all other communications to that web server remain on WAN1.
Q: Do your VPN products interoperate with other vendors?
A: Syswan IPSec VPN products are standards based. This means that any vendor which adheres to acknowledged standards will be supported by Syswan. These standards are recognized by the Internet Security Community.