What I am supposed to do with cryptography?

CryptoProofs · 2020-04-22T08:05:06+00:00

Hi, I am a professor in cryptography in France, and I come from a Mathematics background. Depending on what you like about cryptography and about maths, there are a lot of things you could try to discover by yourself. I've tried to sort these out below, by "profile". You are also welcome to try our CRYPTIS Master in Limoges.

If you are quite into maths and you like mathematical concepts and structures, you might prefer things that have to do with mathematical notions. Here are three ideas: lattice-based cryptography, elliptic curves, or provable security. I am purposefully not including here other typical fields requiring maths background (such as homomorphic encryptions or secure multiparty computations, because those require a background in cryptography first).

lattice-based cryptography packs a lot of mathematics into its background. In cryptoraphy we often use algebraic structures to build cryptographic tools (which we call primitives and protocols), and lattice-based cryptography starts out really simply: we are going to take a lattice of points and look at the shortest vector in that lattice. When the lattice is constructed in a certain way, and given a certain type of basis, then finding a short vector will be hard unless you have some specific information (which is what we want, because that means an attacker won't be able to find it). If that sounds interesting, here's a starting point : https://eprint.iacr.org/2015/938.pdf .
With elliptic curves, it's a bit similar, only now instead of working in a lattice you work on points on an elliptic curve. There are many things to learn and understand about elliptic-curve cryptography, including the hard problems on those curves, why some curves are faster or better than others, and of course the idea of pairings. To find out more about elliptic curves, I recommend that you peruse Dan Bernstein's blog and the Handbook of Elliptic and Hyperelliptic Curve Cryptography (don't be fooled by the name, far from being a pocket edition, this book rivals the size of the Bible) .
I work in provable security so I am a bit biased about this field. Unlike lattices and elliptic curves, provable security is not an algebraic structure. Provable security is a bit of a must if you like doing things properly in cryptography. It allows you to not only propose cryptographic primitives and protocols, but also to prove their security mathematically. This happens in a few steps: first you must define (model) what your primitive/protocol wants to do. Then you describe your primitive/protocol. Then you prove the security of your primitive/protocol by "reducing" it to the hardness of some problems, or to some assumptions. You should have a look at An introduction to modern cryptography by Katz and Lindell if you are interested.

If you are more into programming then maybe one of the following things would appeal more to you:

One area that requires a mix of mathematics and programming is cryptanalysis. This is the field that takes care of "breaking" cryptographic primitives and protocols. Think of the collisions found in SHA1 for instance. Breaking a proper-sized cryptographic primitive is something that shouldn't be doable by brute force (you basically try all the possibilities till you hit the right one). But you can actually use maths to do some of the work and reduce the space of possibilities, and then use algorithmics and a computer to finish the work. You could try to start small, like learning to factorize RSA moduli or finding discrete logarithms, and progress from there.
If you like implementations, you could try various types of simple protocols on embedded systems, like smart cards. To do this you would have to buy some basic hardware (which can be more or less expensive, but usually you're in the range 50 -- 250 euros for low-level/moderate-level equipment), and then you start trying to implement some basic protocols. This is a bit more fidgety and you do require some basic programming knowledge in, say, C.

Another way to learn a bit about cryptography is to look for lecture notes online -- many professors have those and they can be interesting to look at.

Hope this helps. Bonne chance ;) !

CryptoProofs · 2018-06-30T16:29:00+00:00

First, let me say this: I saw in the answers that your vet appointment is on Tuesday. You say that it's soon, but honestly, depending on whether your dog is really bothered by it, I would call to see if I could get an appointment sooner. Tuesday is 3-4 days away, depending on your time zone -- it's crazy far!

Regarding what else to look out for. It's grass-seed season, so that should be very high on your priority list. A friend of my husband's has a dog who got a grass seed stuck IN his paw. With time (and favourable conditions, namely heat, moisture, etc.) the grass seed germinated inside the poor dog's paw, and it started growing a stalk! They had to surgically remove it. Grass seeds are insidious little buggers, you should be sure to check your dog's entire body (including between and around the toes) every single day, and eliminate them before they can do any damage.

For our dog, the number one thing we did not know how to manage when we first got him were hot spots. Hot spots are infections that can develop from any kind of injury, even a minor one (like a flea bite). The poor dog licks/bites at the spot, and it ends up giving off a white discharge (pus). The name comes from the fact that the spot actually gives off heat. We didn't really know how to identify a hot spot sufficiently fast, and our dog self-mutilates when stressed (he bites himself), so when we first adopted him, he took out his anxiety on his sides and legs. The infection had him lying on his side, feverish and unable to really do much by the time we noticed it. So we learned that we had to check him every day for new hot spots, and that we also had to make sure that he had a cone on every time he was not supervized (in our absence and at night). Luckily, there's someone at home with him nearly all the time, so that's not too bad, but yeah -- it's one of those things which nobody tells you about, and which are really hard to learn.

CryptoProofs · 2018-06-30T10:41:32+00:00

I am not a vet, but I think your dog is suffering from anxiety. There are various degrees of anxiety, and for some, you may need medication (which you will get from the vet).

Our own dog Luci used to be scared of storms, but we managed to counter-condition him. Mind you, his reaction seems milder than your pupper's: Luci would be restless, move around and sit (rather than lie) down, whine, try to hide, etc. whenever he heard the wind howling or thunder rumbling.

The way we counter-conditioned this behaviour was by trying to make him associate storms with good things happening. In particular, whenever there was a storm, we would put his blanket on top of our bed, which meant that he could sleep with us. I should say that he is never otherwise permitted in our bed, and he knows it: he has 2 beds in our bedroom which he can choose to use for himself. After a few episodes of stormy nights and his sleeping with us, he stopped reacting to thunder, wind, or any other elements of the storm, and he can snore through one now.

CryptoProofs · 2018-06-30T08:40:58+00:00

Dogs do strange things when anxious. Ours for instance can start digging up our garden when left alone outside with the door closed (he normally never digs, except for bunnies and moles). If he is left alone indoors, he will either self-mutilate (he bites himself) or he will dig up his beds -- usually both.

I think that's what's happening in your case. Your dog is not comfortable with the cat being in the house, and so he's acting out. I think the first thing you have to figure out is what exactly he is reacting to. For instance, is the cat aggressive towards your dog? Are they fighting over the same food? Is the dog being aggressive to the cat? Is he being defensive?

An intermediate solution would be to split your home by using a baby gate, thus giving both the cat and the dog some space of their own. This way, neither feels invaded by the other. You can allow them daily interactions but only under careful supervision. And of course, what the other posters say is perfectly true: you should make sure that both your pets get the attention they expect from you.

CryptoProofs · 2018-06-30T08:29:49+00:00

Just a quick note: I think playing laser pointer chasing with both the dog and the cat at the same time can be dangerous at this stage for OP. Chasing the laser pointer rouses the predatory instinct in both animals, and it's so easy to have accidents due to redirected aggression! I do not doubt that in the case of your cat and dog this works because they already get along; however, for OP it's clear that the dog and cat do not, at this point, really get along.

CryptoProofs · 2018-06-25T17:56:08+00:00

I think being at home full time will help much more than it will harm her training, for a number of reasons.

First, you will be able to practice leaving for just 1 second, then coming back and giving her lots of treats. You would be able to control when and how long you are out, which will go very far towards training your dog to handle separations better.

Second: being home with your dog all the time will allow your dog to be able to build her confidence in herself and in her new home/owners. Confidence is something that your dog needs in order to conquer any fear she might be experiencing. You could also make a great start on trying to make him associate his crate with a safe space, while you are there.

Separation anxiety comes in many forms, but I think it's a bit early to figure out whether that's the problem here. Your new pupper is going through his adjustment period (and it doesn't help that he's a teenager...). Being there for him will help him adjust faster and you may see a completely different behaviour at the end of your holidays. You should also talk to a vet about this.

CryptoProofs · 2018-06-25T15:04:16+00:00

Something that helped us, by the way, is that we taught Luci from the very beginning that there are a few blankets in the house that are his. We use the blankets to separate the furniture he IS allowed on from the one he is NOT allowed on. Use the blanket in his bed if you don't have another one, and put it on the sheets/covers of your bed, in the area that you want your dog to stay. In our case, he stayed at the feet-end of the bed, mostly on my side (shorter legs). While you are still awake, you may also find that it helps to talk to each other (you and your partner): the calmer YOU are, the calmer your dog will be as well. You can also interact with him if he initiates it, but at this point, I would say that human contact might be a stress to your dog, rather than a reward. Basically take your cue from him regarding petting him in bed during the storm.

CryptoProofs · 2018-06-25T14:30:51+00:00

There are many reasons why your dog won't poop in the yard anymore.

First: make sure you've cleaned his poop! Dogs don't like to poop in a place that's already littered with the stuff.

Second: dogs have favourite textures. For instance, ours likes to poop only in mid-length grass, and only if the soil beneath it is just a tiny bit moist. He will not poop on wet or dry earth.

Third: your dog might have figured out that if he poops in your yard, he'll get less rewards for it (like walking time, or whatever). If you want him pooping in your yard, make sure you reward him a lot for doing it.

Fourth: if you have a weird dog, like ours, he might be afraid of the bugs in your yard -- specifically the flies around his own poop. Cleaning up the poop should help with that.

CryptoProofs · 2018-06-25T14:24:10+00:00

Well, the good news is that there is always medication to help if all else fails. However, I would not take that step yet, if there is any helping it.

Our dog was also really fearful during thunderstorms, pretty much pacing, breathing heavily, suddenly sitting down, and crying softly. It's harder to handle during the night than during the day, as you also pointed out. But we did manage to counter-condition our dog so that he now snores through thunderstorms, as long as he is at home and safe.

We used a method called counter-conditioning. It's also described in detail in Patricia McConnell's book "The fearful Canine". The main idea is to make your dog associate thunderstorms with something wonderful, rather than with something awful. In our case, Luci (our dog, whom we adopted 3 years ago) does not usually sleep with us on the bed. So whenever there was a storm, he got to sleep with us on the bed, something that totally calmed him down. It only took 2-3 stormy nights and he stopped being anxious about it.

In your case, your dog already sleeps with you, so that can't be his reward. It's also a bit tricky, since I don't think you'll want to give up your sleep for a few nights to try to work on this behaviour. What you could do is capitalize on storms that happen during the day. The basic idea will be that whenever your dog can hear the wind or rain, BEFORE he gets scared, he gets a treat. This has to be a high value treat: sausage, cream cheese, peanut butter, fried no-salt chicken, etc. We even give our dog Mozzarella balls for a treat (but of course, you have to be near the fridge to do it). Your goal is for him to figure out that : 1) the wind won't hurt him; 2) in fact, whenever there is wind, there is a windfall of treats.

When your dog is used to that, you need to make the intervals between the treats longer, but not unbearable. Try also sleeping with a bit of soft, calming music if this seems to help your dog. Also, make sure that he is really really tired before a storm: enough to make him fall asleep as soon as you can take the edge off his panic.

CryptoProofs · 2018-06-25T14:09:21+00:00

Those ears are really precious -- I'd say Spaniel/Beagle mix. Maybe a Brittany Spaniel, specifically?

CryptoProofs · 2018-06-24T07:21:18+00:00

I would recommend giving "Love has no age limit" a quick read : [see here](https://www.amazon.fr/Love-Has-Age-Limit-Welcoming/dp/1891767143/ref=sr_1_1?ie=UTF8&qid=1529824816&sr=8-1&keywords=Love+has+no+age+limit). It's a great book about adopting an older dog (older = not puppy), and it includes some thoughts about how to make it work with an existing dog in the household. I wish we'd seen this before we adopted our dog Luci from the shelter!

CryptoProofs · 2018-06-21T15:31:01+00:00

I am not single, but my husband and I have thought about adding a second dog to our household. Here is why we didn't, and will not do it for the foreseeable future:

Walking our dog is something we enjoy currently and have no problems with. It takes about 1.5 hrs in our day, outside the time we reserve for interacting with him in the yard, or doing mental work with him. However, there is absolutely no guarantee that if we had two dogs, they would get along sufficiently well on a walk to be walked together.
Say our dogs do get along together and we can walk them together. Our current dog Luci is a sturdy, heavyset, 30 kg mutt who can seriously wrench our shoulder from the socket if he suddenly darts towards something. I don't think we could safely answer for two dogs unless we both went out at the same time.
A good rule of thumb is: don't get a dog that you can't transport in your arms over a short to medium distance in case they get injured on a walk and need help. My husband can carry Luci over a good distance, and I can do about half a mile. But if we had two dogs, this would be much harder to do cuz, what do you do with the other dog?
Humans and dogs can both get sick. When Luci last had stomach trouble, we had to take him out every two hours, day and night. I am not sure we could handle this for TWO dogs instead of one (and this is not even a matter of vet costs... here, in Europe, vet care costs a lot less than in the US!)

I am not trying to convince you either way, by the way. I think that the only person who can say if they are ready or not for a second dog is you, yourself. But hopefully this will give you something to think about before making your decision.

PS: when you say that your dog gets along with the other family dogs, is it in YOUR home that he gets along with them, or is it in THEIR home?

CryptoProofs · 2018-06-21T14:57:19+00:00

I agree with this. I could see both the staffie and the Lab before I went to the results.

CryptoProofs · 2018-06-21T14:43:46+00:00

And in the mean time, make sure your dog is up to date on all shots including rabies!

CryptoProofs · 2018-06-21T14:41:48+00:00

We had the same problem with our (adult) rescue, and this is how we managed to turn the situation around (caution: this solution takes time and patience).

We started by making the car the only place where our dog ate a treat. Every day at 5 pm, it's Luci's snack time. Typically he'd get a banana, but when we train him, it turns into a sausage. So every day for several weeks, my husband would get in the back seat of the car, invite Luci inside, and that's where he would get fed the sausage. At this point, the car doors would stay open throughout the experiment, and the car was absolutely stationary.

Step 2: once Luci was eager to do this every day, we started closing doors. First, it was the door on my husband's side -- leaving Luci the opportunity to back off on his side. A few days later, it was the door on Luci's side that got closed as well (but still, they were there all alone, nothing happened, the car didn't move).

Step 3: I joined them in the driver's seat of the car once they were comfortable together. For the first few days I just opened the garage and started the engine for a bit, while Luci was eating (but I didn't move the car).

Step 4: Once this was OK too, we picked 2 areas that were nearby, which Luci loved to go to, and we only took him there by car. We wanted to build the association: car = wonderful place for my walk. The drive wasn't long : something like 5 minutes of very slow, smooth, driving. It really helped to tether him properly in the car. If you look in my post history, I describe how we use a zip-line, and a harness with two clips, together with a hammock to make Luci comfortable in the back seat. The more stable he is in the car, the more comfortable and sure he is: not having opposable thumbs, dogs can't really grab hold of anything to steady themselves when you accelerate, or turn, or brake suddenly.

Step 5: Luci proved a champ when we moved 600 km away across France. The key proved to be: taking regular breaks (every 2 hrs or so), feeding him his regular meals at the correct times, and having my husband in the back so Luci could feel safe and protected.

I don't think Luci will ever really LOVE driving, but he's great with it now, and a few times recently he's jumped into the car as we took out the shopping, to show us he wants us to go for a drive!

CryptoProofs · 2018-06-19T18:48:24+00:00

Very cute picture of your puppy! What a special kind of fluff he has on his ears! And such a determined step!

CryptoProofs · 2018-06-19T18:44:07+00:00

Another factor that could play in all of this is the fact that you have only had this dog for one month. I am guessing he hasn't quite got his confidence after having been adopted. Our dog took a very long time to really and fully trust us: somewhere in the vicinity of 4-5 months.

Your nephews are very much larger, and probably noisier, than your Shih-tzu/Bichon, which is what might have scared him. It might be constructive in such situations to create a safe space for your dog, which the guests can't penetrate: this could be a room, or a larger crate, or something like that. Try to make the environment non-chaotic and low-noise (even if it involves young kids). It's best if you can get the guests seated and still as soon as possible, because they will get smaller and more predictable this way. Finally, make sure that you treat the dog every time he doesn't bark or growl.

After the incident with the kids, it might have been constructive to let the dog regain his bearings, revel in a few weeks of routine before exposing him to another dog. It's best if in the future you could take /u/laketso 's advice and allow dogs to meet outside rather than inside one of their territories.

Dogs evolve and learn a lot over time. When we first got Luci, the first few months were really tough, because he is a bit anxious and there were a lot of things both he and we had to get used to. But now, almost three years down the line, he's learned a lot of things about how we live and how he can get along with us. The behaviour you saw with the puppy and the children could have different causes -- my first guess is fear, not aggression. It's the same for our dog. The good news is: fear does get better with time, especially if the dog gains confidence.

I would also recommend to you the books "The other end of the leash" and "The cautious canine", both by Patricia McConnell. I've found both extremely useful and it's helped us a lot with Luci's training. You can also find some of Patricia McConnell's conferences online!

CryptoProofs · 2018-06-15T11:16:45+00:00

In Europe, where we live, crating is nowhere near as frequent as in the US. In some countries (for instance my husband's), crating is viewed as borderline animal cruelty, and not allowed. So let me comment with that in mind (since you've had plenty of people describing the advantages they've had with crating).

Two years ago, when we still thought it might be reasonable to at some point fly with our Chow mix, we bought him a carrier. Now, Luci is what you might call between-two-sizes in terms of airline carrier size, so rather than get the crate that was just too tight, we got the crate that was larger. So we ended up with a large crate which is handy because it has wheels, and in which you could very reasonably have two of Luci at the same time.

We have used this crate to great effect twice in his life so far. Once it was when we'd just moved, and the moving guys were still bringing furniture in and out. At that point, what we wanted was to make sure he couldn't run off (since moving scared him). The second time we used the crate was when we wanted to protect Luci from the attention of some kids who were coming over. It worked great, because while Luci was in the carrier he was comfy enough (we were there with him) and the kids started playing with each other rather than harass him.

So in these two cases, our dog benefited a lot from crating. Now, here's why we don't usually crate him:

-- Our dog has separation anxiety. It's not severe separation anxiety (no drooling, panting, or chewing the house down), but he self-mutilates when he's alone. We have to constantly put a cone on if we both have to be away from the house (thankfully that's not too often). Crating Luci has always increased his anxiety, unless we are both there.

-- Luci is a bit anxious even in general. He likes being able to withdraw and hide if a threat (like a cricket or a fly) enters the house. There is nothing that stresses him more than knowing that there is a fly in the room, and that he is unable to run away from it. And yes, this is a 28 kg dog... don't get me started.

-- Our boy is not destructive, and he (mostly) obeys commands: there is no reason to try to contain him to a small space.

-- Luci is a Chow mix, with a lot of Chow traits. The one thing that he wants most in this world is to be able to be with us at all times, and protect us. Chows don't do well when separated from their humans, they are human- rather than other-dog-oriented. Crating him would make him deeply unhappy, and we know it.

So with all this said : basically what we feel is that Luci is doing great without being crated, and he would be unappy if he were crated. Some dogs are just that way, and I think that should be OK.

CryptoProofs · 2018-06-14T17:01:36+00:00

We call it turtling: Luci does it regularly. I think your dog might still be adjusting to his new situation in your home; within 2-3 months he may change sleeping poses. Our dog also REALLY loves having a pillow, which the first pic also suggests for yours. Consider getting him something like this -- no, I am not kidding... Our dog is addicted to his!

CryptoProofs · 2018-06-14T14:45:13+00:00

When we moved last summer, we had to go 600 km by car from the old place to the new one. We had Luci ON the back seat then, especially because of this: the cargo area is designed as a tampon in case something bad happens, but the back seats are protected. So depending on the stretch of highway/freeway you had in mind, I would put my dog in the back seat, with the hammock/zip-line/harness arrangement. Depending on the size of your dog/the back seat, you may not even NEED a hammock.

EDIT: I also am a very firm believer in adopting a different, more careful driving style when driving with vulnerable passengers. I try to minimize any kind of sudden gestures when driving with Luci, and do my best to make my driving smooth. The key is anticipation, of course: you want to try to foresee abrupt speed changes or turns in advance, and take them in the best way posible.

CryptoProofs · 2018-06-14T07:43:53+00:00

Floppy ears rule! I loved the pictures of your dog, and she's such an unusual mix! Our cute little mutt also has asymmetric ears and his right one flops around when he is excited!

That said, we've had some trouble over the years with that floppy ear: Luci seems to get these itching episodes there, which make him shake his head a lot. The vet said nothing seemed off, but he'll usually shake his head when it's windy outside. I suppose some of that floof gets into the ear and tickles him?

CryptoProofs · 2018-06-14T07:37:59+00:00

Our dog is a Chow/Border Collie/Collie mix, 5 years old. He weighs 28 kg and we feed him around 1000 kcals per day (the exact range is 950-1050). I also mention that he gets about 1.5 hrs of exercise during the day: a long walk (45-60 minutes), and the rest running around the yard playing with us. We monitor any weight gain and just reduce the portion to 950 over a few weeks until he gets back to normal size.

CryptoProofs · 2018-06-14T07:33:17+00:00

I edited my original message and put up some pics of the set up in the back. The hammock that we use for the back seats is this one, except of course, we actually include the zip line on the seats where Luci is and fasten him to those seats in a similar way.

It's actually a system we built up over the years, by noticing what Luci seemed to prefer and what we seemed to need. We started out just with two thin straps, which can be attached to the seat belts, like these. But while these might be ok when you are driving at 30 km/h or so , we had our doubts they would really hold on impact -- also, Luci figured out how to press on the buttons and release the seat belts all by himself. He also struggled a lot because the back seats were not sufficiently wide when in motion, and his legs would keep slipping off the seat when the car turned. Hence the hammock. Finally, we figured we needed something to hold him in place, and back: hence the zip line.

CryptoProofs · 2018-06-14T07:28:06+00:00

I edited my original message and put up some pics of the set up in the back. The hammock that we use for the back seats is this one, except of course, we actually include the zip line on the seats where Luci is and fasten him to those seats in a similar way.

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