Overview
The /Exinda, coming with default Application definitions, classifies traffic in part due to those Applications. One such classification is Instant Messengers. In the past, a popular instant messaging application was MSN Instant Messenger (IM), from Microsoft. The classification in the /Exinda is meant to find all MSN Messenger traffic and put it into appropriately defined policies. It has been found that traffic to MSN.com (the news/homepage) can be classified as the Application MSN in the /Exinda, and while this inherently does not pose a problem, it can adversely affect users if there are policies out there to throttle or discard all IM traffic.
Root Cause
MSN.com used to house servers for the IM on subdomains. The MSN Messenger Application and as a result, some traffic to the website of MSN.com, can be classified as MSN. If there are any policies that block the IM Application group or the MSN Application, users might not be able to access the MSN.com website.
Information
As of October 2014, Microsoft has shut down MSN Messenger to migrate their services to Skype. Skype has its own definition in the /Exinda. Since the MSN service no longer exists and all the servers for it have been shut down (which means there is no real MSN IM traffic out there), it is safe to consider all traffic that is classified as MSN is actually traffic to the website MSN.com.
If there are policies on the /Exinda to block or throttle the Instant Messaging Group, traffic to MSN.com might be unreachable or slow. If this is the case, in order to keep blocking IM, it would be safe to remove MSN from the Instant Messaging Group by performing the following on the /Exinda:
- Navigate to Configuration > Objects > Applications.
- Under the Application Groups tab, edit the Instant Messaging Group.
- Find MSN in the list of items belonging to the group, and change it to be blank (at the top of the drop-down list)
- Click Save Changes.