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Comment Re:Not unlimited. 7GB (Score 1) 242

Since the IP address of my PC is on a subnet local to my phone and my PC, different from the subnet used between my phone and the carrier, I would say NAT is used.

I'm telling you, and you can contact the network technicians at your carrier to verify this, that there is, indeed, NAT involved (in fact, we agree on this part). Carrier grade NAT on the carrier's network, not on your phone.

The IP space of the AdHoc LAN created when you wi-fi tether is, of course, local and quite likely on a different subnet than the one over which your phone talks to your carrier. That's how 1:1 routing works. 1 IP internal to your LAN routes to 1 IP external to your LAN. That is not NAT. It's also not pandering to the carriers; it's the very same thing dumb phones that allow tethering do. Back before 2G, it used to be circuit-switched data, your phone actually acted as a modem and you'd dial in, but tether-capable phones have been doing 1:1 routing for at least 2 decades now and today's phones use the same infrastructure. If your phone is doing NAT, it is doing you a disservice, because your carrier is, as well. The reasons for this have already been explained, but I'll take another go since you apparently completely missed that.

By the time phones technically gained the capability to perform NAT locally, we were already running out of IP4 addresses. There is not enough address space remaining to give each prone two separate public IP4 addresses, one for mobile and one for tethered data, the infrastructure is already in place to not need to do local NAT anyway, and doing local NAT would strain the CPU, RAM, and battery of your mobile device. As a result, mobile OSes don't implement NAT as we commonly talk about it, because it would be a battery life and performance killer and other solutions already exist; that's not to pander to the carriers, that's to make their products look better on paper and perform better in reality.

Actually... and I'm going to leave the above post as-is because it's all pertinent information... technically, yes, 1:1 routing involves translating network addresses. It's not NAT as we commonly talk about it, where one public IP is shared among many private devices, but yes, it is translation of network addresses, so from a very pedantic standpoint, it's NAT and yes, it is done on your phone. It lacks all of the connection and endpoint tracking functionality we commonly refer to as NAT, though; it's literally "anything coming in to this IP forwards to that one" and is commonly done in the radio chip itself, which certainly does not support what we commonly refer to as NAT.

Comment Re:Not unlimited. 7GB (Score 1) 242

Your phone is acting as a router, yes, but not NAT. Here's a test: Visit from your phone. Now, tether your laptop or tablet and visit from there. Same IP? If so, you're right, your phone is doing the NAT. Different IP? Different routing and carrier-level NAT. Simple test, really.

On T-Mobile with a Nexus 6 using the Android built-in tethering, my phone and tethered laptop have different public IP addresses. If the phone was doing NAT, the IP would be shared. Your phone is doing simple 1:1 routing of internal to external addresses, no NAT unless you're using something like Barnacle. Android itself does not do NAT. Period.

Comment Re:Where's yours is a better question... apk (Score 1) 242

but, you guys constantly "harass" me

Which is funny to me, considering that our first interaction was you harassing me. As for whether or not I was on topic with my post earlier in this thread (in reply to the AC who first mentioned your name); the topic of the post I was replying to was how unwelcome your posts are and I was exactly on that topic. The AC may have been off-tpoic with his post, but my post was definitely in line with the topic he opened up.

Either way, I think the whole thing is rather amusing. Honestly, your constant posts about the hosts file are hilarious. Other than the repetitive and rambling nature of your posts, I don't see why people take such issue. Had you not attacked me in that other thread (unprovoked, at that) I'd have nothing against you; but you did, and I do. Mind you, I'd still have posted the same thing in this thread, but would have done so in a joking manner; now, I'm dead serious, you've really gotten that bad.

And yes, dozens of similar posts in a single thread is spam, I don't care how on-topic it may or may not be. To be clear, I'm referring to the following wording from that page: "Forum spam is the creation of advertising messages on Internet forums" and, as Slashdot (like other forums) is modeled after Usenet, "Usenet convention defines spamming as excessive multiple posting, that is, the repeated posting of a message (or substantially similar messages)".

Comment Re:Not unlimited. 7GB (Score 1) 242

The fact that they are routed to different APNs and identifiable by the carrier is itself a violation of net neutrality

Howso? I suppose, next, you'll claim that the fact that there is yet a 3rd APN involved in sending and receiving MMS messages is another violation, and a 4th network that routes voice, that's another violation, right? Better start filing those reports with the FCC then.

The reality is that there are actual technical reasons for routing tethering traffic through a different APN (which is done at the device leve, on your phone, by the way), not the least of which is that not every phone can do its own NAT (in fact, until a few years ago, the majority couldn't, the processing power and RAM just didn't exist in a device that portable) and even today where most technically can, the majority don't, partly because there is no need (the split infrastructure is already in place). When you use mobile data, your phone gets its own public IP address, which your carrier can manage because they know one subscribed device = 1 IP; when you tether, your session is routed over carrier grade NAT, sharing a public IP with many other devices, which is necessary because the carrier does not necessarily know how many devices you might tether at any given moment, far enough in advance to ensure that they have enough available IP addresses for everyone to use. Since most phones aren't also routers capable of performing NAT locally, this, again, is a necessity.

Comment Re:Not unlimited. 7GB (Score 1) 242

They shouldn't even know if the data is coming from the phone itself or via tethering. Doing so is a violation of net neutrality, and is a bad thing.

Doing so by way of packet inspection is a violation of net neutrality. However, mobile data and tethered data are routed via two different APNs, which is the mechanism by which T-Mobile knows which is which. If you think it's not obvious what's going on when you go from 100MB mobile 7GB tether, to 7.1GB mobile 0GB tether, to 2TB mobile 0GB tether, either you're an idiot or you think everyone else is.

Comment Re:And if they screw up, good luck getting it fixe (Score 1) 242

I've found that there is usually a 3 month period between when T-Mobile releases a feature or plan and when the reps know anything meaningful about it. Consistently, I add features as they are released and have issues for 3 months thereafter, at which point everything is magically fixed, credits issues, a month of service comped, and life goes on.

It's gotten to the point where I'll add the feature and just expect to call them when the next 3 bills come out. I don't bother following up, I just make sure I've contacted them and it's documented; then, like clockwork, on the 3rd monthly call, everything is resolved, I'm credited for any overpayment or missed service, and given a credit for the next month's service as well. Like. Fucking. Clockwork.

All great discoveries are made by mistake. -- Young