Neither your KOreader problems nor your iptable problems have anything at all to do with this thread.
Use the KOreader thread for KOreader problems.
Start your own thread for your iptable problems.
And yes, iptables has always been there - the Kindles have always run a strong firewall.
So first, check what you are doing that makes you think they are not included in the stock (customer, not factory) firmware release.
See:
http://www.catb.org/~esr/faqs/smart-...45835691837744
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