So, a key concept here is that Hosts don't have a physical location.
This is less true in 6e, BTW: "Some hosts exist entirely virtually and appear as floating above the black plane of the Matrix, while others are attached to physical hardware at a specific location." (6e CRB pg187)
Granted, yes if a host is said to have an explicit location, then you can measure distance. However, for the purposes of consistency I believe that even in those cases you "should" just ignore distance between that location and the location of any devices that are part of the host's network. 1) it's kinda silly for it to work differently for two otherwise identical hosts and 2) when playing published materials, they don't really (if ever) specify whether the host has a physical location. And again, even if it does have a physical location, who's to say it's in the same building, sprawl, or even continent?
Leaving that aside, however, do you believe you can enter a host while you are stood inside a perfect Faraday cage, with infinite noise between your commlink and every other Matrix device on the planet? If so, how? If not, why not?
As I read the RAW: when inside the faraday cage you only have infinite noise between your commlink and every other device outside the faraday cage. Another device inside the cage with you has no Noise (unless of course it's a huge cage and there's enough distance to generate distance based noise). Now this might on one hand seem stupid, on the other the matrix doesn't work on TCP/IP transmission protocols.. or frankly anything else other than what is ultimately "Magic". So...whatevs. Rules say it works that way, so that's the way it works. (disclosure: note that the guy who writes the matrix rules doesn't necessarily agree with me here. I'll let him explain his views rather than put words in his mouth...)
Now with regards to wireless negation technology, that involves physical locations. If Charlie the hacker wants to hack the building's host, then the paint/wallpaper doesn't affect his actions. How can it, when the host isn't inside the building?
Indeed!
Indeed, indeed!

But we segue into...
However, any devices inside the host do have that "noise barrier" between them and Charlie. So even if you hack into the host, dealing with devices inside that physical area (like, say, a file archive, cameras, etc) ARE getting the bonus Noise versus Charlie's actions.
But there's no noise between icons inside a host, right? (Although on closer inspection, I cannot find any text in 6e that says this. It's probably there somewhere.)
The way I read wireless negation (and faraday cages, with regards to the physics-defying matrix) is that they are barriers rather than fields. Granted, the barrier must usually fully enclose a device in order for the negation to apply because there's not necessarily any need for a matrix communication to take the
most direct path between two physical locations. IIRC this non-reliance on the most direct path between two points is assumed rather than said... but if you DON'T presume this, then you have to start considering all the potential sources of interference between to distant points rather than the immediate areas around the two. So for simplicity's sake... I believe it's best to assume matrix comms "magically" find and take the path of least resistance. Ergo if you don't physically enclose wireless negation around a device, then there's no wireless negation.
And while my understanding requires the barrier needs to encase a volume, it's still not imposing noise on that interior volume... it's only a box rather than a solid brick of noise throughout the interior. Communication going into or out of the box is affected. Communication never going inside the box is obviously not affected, but the wrinkle is neither is any communication between two points inside the box affected by the box!
Or is your interpretation there is no distance based noise between icons in a host, but there can still be interference based noise between them? I can't find anything about this on a quick skim in 6e, but in 5e, there's "If you are in a host that has a WAN, you are considered directly connected to all devices in the WAN." which to my mind suggests noise never effects anything within a WAN.
So, if the host has no physical location then it's irrelevant if you're inside the box or outside the box. And if the host DOES have a physical location, then maybe it should now matter logically... but I prefer to think that it doesn't, for consistency's sake (as explained above). All it takes to suspend my disbelief is to say that commlinks/cyberdecks/RCCs can't communicate with their networks in whatever way hosts do that allow them to "see through" wireless negation.
If so: Charlie sits outside the building and hack the host, enter the host, and sends a hacking command to (say) Bob's commlink. Bob's persona is in the host, Charlie is inside the host. The wifi blocking paint is between Bob and CHarlie and yet an argument can be made that the paint does nothing. Yes?
...
I'm struggling to see what wifi blocking paint does now. You can always hack into the host from anywhere. Once inside the host, you are "directly connected" to everything else in it, so can hack into that too. Doesn't seem like the paint does much for the corp to improve their security.
Ok, Charlie is the hacker "outside the box" of wireless negation. He enters the host. The host can talk to Bob the security guard's commlink without suffering Noise, but Charlie is not the host. His icon is inside the host yes but his physical location is still outside the building. Doing anything to Bob's commlink, whether Charlie has hacked into the host or not, suffers Noise.
They likely aren't making any hacking actions, and therefore don't care about Noise.
I've seen this idea floating around that noise only affects hacking actions. I can't find much evidence for it in the book. CRB pg 176 defines noise as "Noise represents any interference between a user and their target. Noise can be created by sheer distance or other factors, such as jamming or obstructions." Nothing about legality.
Looking across the actions list, there are plenty of actions explicitly listed as legal that noise affects (eg. control device.) Suggesting the matrix actions tagged as "legal" are "hacking actions" because they are effected by noise doesn't sit right with me. Encrypt File is a good example. A legal Matrix user might need to encrypt a file. It is marked as a legal action. It requires a test (to determine the encryption rating.) Does a wageslave potentially suffer a noise penalty to encrypt the file they are working on?
The presumption is that MOST legal actions don't/shouldn't involve dice tests. Controlling drones is the obvious exception, of course. You don't roll anything to make a commcall. You probably shouldn't have to roll anything to update your contacts list in your commlink, even though that'd be governed by the Edit File matrix action. Basically, the only reason the wageslave would really roll to encrypt a file is because it's setting the difficulty for a future hacking action. Subtracting dice from an activity that doesn't even have a roll is a mechanically meaningless "penalty".
So, technically, in the case of the wageslave encrypting a file while that wageslave is inside a "box" of wireless negation... it depends on whether the file is out on the host or "directly" stored on a device. On the host: no noise, assuming the commlink or terminal is part of the host's network, of course. Not on the host: it depends on whether there's a wireless negation barrier between the wageslave's commlink/work terminal and that destination device.
Which brings me onto my next point:
However, any devices inside the host do have that "noise barrier" between them and Charlie. So even if you hack into the host, dealing with devices inside that physical area (like, say, a file archive...
You suggest that Charlie might have a noise penalty when working with a file that is inside the host.
That suggests the file icon has a physical location that is inside the wireless blocking wallpaper, while the host does not. Was that your intent?
I bolded part of what you said, because it's an incorrect characterization of what I said. No, I said he'd potentially suffer noise if the file was on a device behind a noise barrier, NOT on the host itself.
As far as I can see, you should never have a noise penalty when hacking files from a host, as you have no penalty to reach the host, and the files are inside the host.
Yes, on that we're agreeing.
Whether Charlie is inside or outside of the box (or, through bizzare RAW, even inside a farraday cage! but surely that's not RAI...) he's not suffering any noise talking TO the host nor doing anything inside the host once he's inside. If the file has no physical location and exists solely "inside" whatever device/magic makes the host, then there can be no measurable distance between Charlie and that file.
(And I got slipped by 4 messages while typing this up! will review and respond if my opinion is warranted after this post

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