There are two kinds of "IP Feeds" or lists of IPs to block:

1) Remote IP Feeds
2) Local IP Feeds

Remote IP Feeds download their contents from a URL everytime they are used
so even though you may see .txt files for them they ARE NOT static lists.

Local IP Feeds are based on a file path and are static lists
which can be manually updated.

The type of feed and its URL or file is specified in the Feed*.xml files.
