The basic difference between Security groups and distribution group is
Security groups can be used to assign security rights on resources inside your Windows 2003 Active Directory network. By using a security group, we can collect a group of user accounts in a department and assign them access to a shared folder. We cannot use distribution groups for this purpose and a security group has all the capabilities of a distribution group.
A distribution group can be used for sending emails to a group of users. We cannot use distribution group for assigning security permissions. A user’s membership in many security groups could result in slow logon performance. Therefore distribution groups should be used wherever possible.
Security groups can do the same things that a distribution group can do with the added advantage that they can also be used to assign permissions to files or shares whereas distribution groups cannot.
More basic differences are
The difference between a security-enabled group and a non-security enabled group
is that a security enabled group will be present in the kerberos cert and
authentication tokens for a user when they logon. This is used for the Windows
NT security model.
Hope this helps.
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