Much like a cross between Goldfinger and View to a Kill.
Dr. Evil: You know, I have one simple request. And that is to have sharks with frickin' laser beams attached to their heads! Now evidently my cycloptic colleague informs me that that cannot be done. Ah, would you remind me what I pay you people for, honestly? Throw me a bone here! What do we have?
Number Two: Sea Bass.
Dr. Evil: [pause] Right.
Number Two: They're mutated sea bass.
Dr. Evil: Are they ill tempered?
Number Two: Absolutely.
Dr. Evil: Oh well, that's a start.
One really needs to define "emergency". There isn't an "overall" data link layer protocol. Every area is different it seems.
I know that some use Motorola DataTAC and ARDIS data.. but that's back in the day.
And that the company I work for provides link layer services for TEMPEST Telemedicine products:
* UNIX is a Trademark of Bell Laboratories.