Resolution:  Canvas Support has identified and resolved the issue.  Please contact the ITS Help Desk if you have any further problems using this service.
Update:  We've learned the Canvas authentication systems are experiencing an issue which is causing intermittent access from the Icon Dashboard to Canvas.
Users can expect to login to https://icon.uiowa.edu, but navigating to Canvas thereafter will intermittently give an error that reads "failed to login".  Canvas has also reported that some services in Canvas, such as SpeedGrader, are experiencing issues as well.

Original Notice:  The Canvas service is down.  Support staff are working with Canvas Support to resolve the issue as quickly as possible.  This notice will be updated once we have more information.