Evaluating SSH Security: Alternatives To Port Knocking For Access Control

The robots currently at work knocking around for your guessable password could easily be repurposed to guess your Unicode password currently known as your port knocking sequence, and quite likely have been already. Plus, we already have authpf(8) for network-level restrictions on access. Whenever you write about security in general and SSH security in particular (and for good measure also get slashdotted for your efforts), the comments inevitably turn up a variety of useful and less useful suggestions.

The link for this article located at That grumpy BSD guy is no longer available.