Konig Electronic WLAN router 300 Mbps - Manual (Page 32)

(1.2.3.100-1.2.3.149) Remote hosts are allow to send mail (port 25), and browse the Internet (port 80)
(1.2.3.10-1.2.3.20) Remote hosts can do everything (block nothing)
Others are all blocked.
Example 2:
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