Maximum Connection Size
The Maximum Connection Size shows the maximum size (in megabytes) of articles that users can post before NNTP disconnects them. The default Maximum Connection Size is 20 MB.

If you set this amount to 0, users will be able to post articles of any size.

You should set the Maximum Session Size to a size that protects the NNTP Server from being overloaded by a single user. For example, you can prevent a user from posting files that total more than the Maximum Post Size.