Which raises another question...just how fast are runners actually going? Sure, the actual boom boom, fireball, crash the O/S can go incredibly quickly...but if you intersperse things like staying under cover, and a desire on the OPFOR part not to die (does that lone star cop really stick his head out and send a few rounds down range every three seconds, or does he maybe just stay behind the dumpster for a short breather while his bud jabbers in the commlink.) Mexican stand offs can burn away precious time.
100 combat turns for 5 minutes sounds like a ton, but when you factor in the period where players are not sending long bursts of sabot down the corridors, 5 minutes can bleed out pretty quickly. Especially if you keep players on the clock for their own decision making (not at a one to one ratio mind, as they are not, after all, hardened covert ops types with computers linked into their brains conducting ARO augmented chat) but if players take 5 minutes between themselves trying to figure out how they are going to get out of the current SNAFU, its fair to say a 30 seconds have passed.
And for some facilities, mere travel takes time. How long does it take you sprinting full out to go up (or down) 4 flights of stairs? The rules have a sprinting runner doing 200m (50m equiv in a flight) in 8 turns (24 sec)...the point being, even in a full rehearsed, by the numbers, following the blueprint hyper aggressive run, lots of time gets bled out doing things unrelated to saboting a guy in the face.
And do you stack every combat turn chock full o combat even when the shit has hit the fan?
Its very conceivable that after the alarm most of the security forces spend the first minute, 20 combat turns, just getting their acts together. Sure, the firewatch guys have already sent everythign to tacnet, analyzed it, made a plan, and are converging on the players as every system in the building begins cyberwar...but most lone star grunts take a little human processing time to get a hold of whats happening, and then synch in with what to do. Rent-a-cops may just say "Go to corridor three and stop troll? Oh helll no, my job is hit the alarm button and watch the showers with sec cam. I am staying right freakin here"
Here's Another one, for perimeter security.
Containment Doctrine (professionalism 3+)
Rather than try to hold the line every step of the way, the corp saves on time, personnel, and money by maintaining strong points at key transit areas and vital parts of the building, using the rest of territory as a giant delaying zone. Enough gadgetry to keep the thugs out and identify entrants, but for real serious defense, the corp relies on being able to call up additional forces. the intial on site gear uses a series of ambushes and simple barriers to keep intruders moving slowly or making them run away before they get to where they can do REAL cred damage. You don't need to splatter all of them in one chaingunned wash of fire when a handful of light pistol armed ferrets can make moving through a cubicle block deadly if you don't slow down...
Your composition may vary on target size, terrain, and value, but here's the basic philosophy:
Perimeter: Enough to stop crimes of opportunity, with key entrance ways under checkpoint with heavy slow down measures. No sense in letting a carbomb in the front gate. patrolling is light (and may not be any depending on the target) and pre-dominantly unmanned. Hardwired sensors to security supplement the usually wireless sensor suite. Wired motion sensors are exceptionally useful as they either slow down intruders and leave them in the perimeter so long that SOMEONE will probably see them, or the alarm will start wailing. Security here has a simple rule: Don't take a fight you can't handle. Go to ground, raise the alarm, and stay alive. The information you send inward lets security position its disruption force. If they got past you before the alarm went up, close down the outside, and be prepared to coordinate with the relief forces when they arrive.
Disruption force (inner perimeter): Initial security role is backstopping the outer perimeter and is treated much the same way. And yes, its cheap. It has two roles: If intruders are coming through the perimeter, slow them down. Whether this is simply dropping rolls of c-wire down the stair case for an abandoned tenement, or hardlocking all the doors in a research lab and then dropping them off the network, the concept is simple. Make it a painstaking, slow, PHYSICAL, process to get through. Armed forces stage hit and run ambushes, but don't act decisive. They aren't trying to finish the fight here, just make sure the runners can't sprint through the cubicles without worrying that someone may smartlink around a corner or that they bypassed a ferret who's gonna shock down their hacker behind them.
If intruders raise the alarm inside, then seal, and prepare all actions to prevent them from coming out. Be prepared to re-establish whatever strong point they burn through on the way in, closing the door behind them.
The orders are once agains simple: Stay alive, keep harassing the runners, don't let them get this free. its more important that you hold them up for a few than you all heroically die to bring down the troll gunner. You'll get your crack at them again on the way out, or the response forces will toast them.
Strongpoints: At key bottlenecks and around vital areas, use those outer perimeter savings on creating a handful of positions that can seriously hold the runners up. Whether thats rail drones and a fully gasable hallway, a basic scan checkpoint, or something as easy a knocking some firing loops in the plaster overlooking the stairs, these are the points where metahuman on the scene judgment will always be available, and well fortified enough to take the runners a bit to crack. If they are dumb, this is the line where dirt naps become likely. Obviously, if the alarm was raised on the way in, the runners can expect to be hit hard when they get here. If the alarm is raised past them, the checkpoints lock down and orient inwards. Use of obstacles and fortified positions helps keep runners in the killzone long enough to seriously hurt them and slow them down. Hopefully long enough for
The internal reaction force (fixing force): This is the do or die line. The Execs body guards, or the local reserve in the building,the final guards on the biotoxin lab door...they do one of two things: Protect their principal, or reinforce whatever strong point is under attack. They aren't here to clean sweep the runners, they are here to make sure the runners don't get the MacGuffin. Whatever makes that more likely, they do, but this is do or die time. Cause really, given all the runners have gone through, if they can hold out just a little...bit...longer...help is on the way. Big help.