ASTA clients typically connect to an ASTA server using an IP Address and port number. ASTA servers scale quite well but there may be times when you want to have fail over abilities with multiple servers or just have too many clients to be handled by one server. Figure shows a typical ASTAServer connected to by remote ASTA clients.

The ASTA AnchorServer provides load balancing and fail over abilities. Instead of clients connecting directly to a remote ASTA server they connect to the AnchorServer which then finds the next available ASTA Server and sends back to the client the IP Address of that Server. The Client Disconnects from the Anchor and connects to the ASTAServer designated by the Anchor.

Figure shows ASTA clients connecting to the ASTA AnchorServer. The AnchorServer maintains a connection to running ASTA servers as a client itself.

The AnchorServer can be configured to connect to any number of ASTA servers. When the Anchor starts up it will attempt to connect to all the ASTA servers and will display the current status of each server. Screenshot shows the ASTA Anchor configured to connect to several remote servers.

When the Anchor Server starts it can show the connected number of users for each ASTA Server as seen in screenshot.

If an ASTA Server goes down, all the remote users from that server will be disconnected and will then connect back to the AnchorServer which will hand them off to other ASTA servers. This is Fail Over. One of the advantages of the N Tier architecture is that once you design your ASTA client application it can scale simply by adding more ASTA Servers to be used with the ASTA Anchor Server.The ASTA Anchor Server requires multiple ASTA server licenses so that it is not available in the ASTA Entry Suite. The Anchor comes with complete source code so that any encryption and compression routines can be customized and is available as part of the ASTA Power Pack which includes ASTA source Code, 3 ASTA Server Licenses, an Unlimited Single User License, the ASTA Component Suite and the ASTA Anchor Server. The ASTA Power Pack is priced at $1999 US and any previous ASTA Entry Suite Purchases or AstaServer Licenses can be applied to the ASTA Power Pack.

About the Author

Steve Garland, a founder of the ASTA Technology Group, is the chief developer of the ASTA product line. Steve can at sgarland@astatech.com.