job screening question

Oliver Garraux oliver at
Thu Jul 5 17:11:38 UTC 2012

Seems fairly straightforward to me.  It'll break path MTU discovery.

I would hope someone applying for an "IP expert" position would know that.

Could HR be mangling the question or something?



Oliver Garraux
Check out my blog:
Follow me on Twitter:

On Thu, Jul 5, 2012 at 1:02 PM, William Herrin <bill at> wrote:
> Hi folks,
> I gave my HR folks a screening question to ask candidates for an IP
> expert position. I've gotten some "unexpected" answers, so I want to
> do a sanity check and make sure I'm not asking something unreasonable.
> And by "unexpected" I don't mean naively incorrect answers, I mean
> oh-my-God-how-did-you-get-that-cisco-certification answers.
> The question was:
> You implement a firewall on which you block all ICMP packets. What
> part of the TCP protocol (not IP in general, TCP specifically)
> malfunctions as a result?
> My questions for you are:
> 1. As an expert who follows NANOG, do you know the answer? Or is this
> question too hard?
> 2. Is the question too vague? Is there a clearer way to word it?
> 3. Is there a better screening question I could pass to HR to ask and
> check the candidate's response against the supplied answer?
> Thanks,
> Bill Herrin
> --
> William D. Herrin ................ herrin at  bill at
> 3005 Crane Dr. ...................... Web: <>
> Falls Church, VA 22042-3004

More information about the NANOG mailing list