0:00:13 | so for of a let's oil they and so is yes we can do what to but the computation of |
---|---|

0:00:18 | uh every for you can compute everything in the group the domain |

0:00:21 | the question is our fusion |

0:00:22 | so that me start by saying what the what is more D the computation |

0:00:27 | so uh went to day now there's you go online line in to play park or what happens is that |

0:00:30 | you are here with your friends and a on a |

0:00:33 | online server |

0:00:34 | you connect to some central that service that is the for you |

0:00:37 | and then gives to the card and then you can play pocket |

0:00:39 | but course what happens if uh |

0:00:41 | uh you playing with power what happens if the central server is ga a controlled by a it and there |

0:00:46 | is one of the play is also part |

0:00:48 | well than they can easily like a a low together right and then the the part of controlling the survey |

0:00:53 | can give very good cards to is the this find then but as everyone it |

0:00:58 | so might about the computation uh at about the combination is uh all the sets of the cryptographic techniques that |

0:01:03 | allow you to instead of having the central server |

0:01:06 | the second to split the the to in the service i'm among the players so everybody has run a piece |

0:01:11 | of software on their machines |

0:01:12 | that um rates the that simulates the presence of this that serve |

0:01:16 | oh oh do these you know way that even if everyone else is a pilot uh then you can sleep |

0:01:20 | play poker |

0:01:21 | uh very |

0:01:23 | because we don't wanna as mine |

0:01:25 | so |

0:01:26 | this is gonna be a |

0:01:28 | how a technical talk up not |

0:01:29 | and i is something about the the application of and P C and uh are the been using the real |

0:01:34 | word |

0:01:35 | i'm gonna to find a security model because a market at are for so i like security definitions |

0:01:39 | and then i'm gonna present just to of the results of that think you should be aware of |

0:01:43 | uh one because it's very important and other one is because i done it so i think if you know |

0:01:47 | about |

0:01:48 | um |

0:01:49 | so let's start from the beginning |

0:01:51 | so not about the computation of been introduce uh a more than a almost thirty years ago by and the |

0:01:55 | we out |

0:01:56 | uh but you have to wait until at to the the yet two thousand to that seeing the first efficient |

0:02:02 | solution |

0:02:03 | the that |

0:02:04 | can be using in practice uh |

0:02:05 | so that from two thousand you see a lot of uh |

0:02:08 | but the types an implementation of uh |

0:02:10 | but the goes from about the computation |

0:02:12 | and that because some of them P C a a |

0:02:15 | by you so |

0:02:16 | in that wording electronic action privacy was every |

0:02:19 | privacy preserving operation see "'cause" you know processing so basically every time you want to compute on something and you |

0:02:24 | can about the privacy of your input |

0:02:26 | and the correctness of a result |

0:02:28 | you want to come in not cut the mpc dot |

0:02:31 | so for instance a a a a this is a a start from a then use paper |

0:02:36 | uh uh then is people are uh ensure the they have had insurance and then when the get seek a |

0:02:40 | uh they they have |

0:02:42 | big problem them man you like the six uh are they have to a about the signal and the get |

0:02:46 | to to the insurance and ask for their money |

0:02:48 | this a problem because the see people could enjoy this is mine and |

0:02:51 | could that them to to do with their problem |

0:02:53 | and uh so on is a solution of this could be that i be that's an insurance company could perform |

0:02:58 | form uh the intersection of the database base once you know i to check |

0:03:01 | we should get some mine |

0:03:02 | of course this is a privacy present these is a privacy sensitive |

0:03:05 | uh kind of computation because |

0:03:07 | you don't want the medical records of |

0:03:10 | the patient to be square as or the in for insurance data |

0:03:13 | and we can solve this problem using a C |

0:03:15 | oh example was the from a from then mike |

0:03:18 | uh these the is the a base the first the time that and P C has been used to move |

0:03:22 | real money |

0:03:24 | in this case the so |

0:03:26 | should should this missing then mike the they you have a should that contract is a bit contract so they |

0:03:30 | are be you know that's them |

0:03:32 | a many should is they can grow i mean you get be they can set |

0:03:35 | and uh the can exchange is these objects these objects are like or C and the wanted to that are |

0:03:39 | mean you know the the price of |

0:03:40 | with for exchanging this kind of comedy |

0:03:43 | so you can do a an option i everyone is i want to buy a this price i want to |

0:03:47 | buy so much of this price and |

0:03:49 | then that it can |

0:03:50 | make is nice by find the equally equilibrium point |

0:03:52 | but the farmers as don't want to tell each other are much they were willing to buy and sell for |

0:03:56 | because that to be as information about their own farm |

0:03:58 | and uh then is is a very technological advances so they use mpc P C |

0:04:03 | to to to the mean this price |

0:04:04 | uh the problem the computation last on thirty minutes |

0:04:07 | and that's uh is that back call is that not |

0:04:09 | well if it's a task that have to do only once a maybe is good |

0:04:13 | and for that's a motion are probably a kind a we kind of security so passive security and uh it |

0:04:18 | assumed that the magic of the party to be honest |

0:04:21 | and that i don't like uh |

0:04:23 | i |

0:04:24 | being the mean value of don't believe that the harness is the that a much as of people are honest |

0:04:29 | so i another example that that are the from last week a is that the there is an L on |

0:04:33 | tongue and group of people that |

0:04:35 | more less to the same they have a nice website we a nice logo |

0:04:39 | and uh so i C to company scene is tongue the wanted to benchmark a i guess each that they |

0:04:43 | want to do a whether for |

0:04:45 | i'm do we by are employ use so much revenue you we get four |

0:04:49 | money we spend and they want to to compare information with each other the one i stack statistics |

0:04:53 | uh uh of course these this |

0:04:55 | all season for the uh these data is the |

0:04:58 | to be get it so that using uh and P C to do this |

0:05:02 | but as a nice solution was the share mine |

0:05:03 | only gives you this kind of weak secure |

0:05:07 | so what is the security model i keep saying security T but what do i mean when i a secure |

0:05:11 | so a first of all can this computation to me computation is just a quit |

0:05:15 | well we have a |

0:05:16 | from now on um only gonna talk about two five is but you can generalise to more so the have |

0:05:20 | and your bob that have some input |

0:05:22 | let's say that beats right we can do everything the bit |

0:05:25 | and the want to some with made a multiplication addition on this bits |

0:05:29 | so that is computation from |

0:05:31 | so computation means that every all the input i get by it that's why there is a a the log |

0:05:35 | that to show that these |

0:05:37 | uh input that product and that's all the gates are encrypted because all these the internal values should be |

0:05:42 | uh a get by but also a of the it should be encrypted that in the sense that they |

0:05:46 | a the should produce that i with they should be sick you L the get to be sick |

0:05:51 | in particular it a is crap it she's up by she should be able to do things like a all |

0:05:55 | i want to learn |

0:05:56 | this intermediate audio or or maybe |

0:05:58 | i one the output to be these beat that i design |

0:06:01 | yeah does that |

0:06:02 | uh problem problem in terms of privacy and correctness |

0:06:06 | so do the mean wanna say secure |

0:06:08 | uh this is kind of a card last year because they come from the could start a few what most |

0:06:12 | of you come from the |

0:06:13 | signal processing work |

0:06:14 | so |

0:06:15 | intuitively we are agree that a locally secure if no one can a it if not not back again |

0:06:21 | learn an information |

0:06:22 | unfortunately approach security is |

0:06:25 | a a a a a lot X |

0:06:27 | uh uh isn't a list of a tax there isn't a book that you can buy where you read a |

0:06:30 | lot X and then you |

0:06:32 | reasons uh any such a thing maybe you make your system C Q against that kind of a tax and |

0:06:35 | then to more they come up with the |

0:06:37 | another kind of attack and then what do you do |

0:06:39 | so in cryptography |

0:06:41 | uh we believe that security is not a probably they can be checked empirically |

0:06:44 | so what we do we want to prosecute |

0:06:47 | so but it not for the case of multi body computation the stand the model of a for probably security |

0:06:52 | is the i don't work i real work by like |

0:06:55 | so |

0:06:57 | the top or the or what they called the i word is what you want |

0:07:00 | so you want you have a T symbol |

0:07:02 | you want what you really like is that the magical about where you can put a input and get the |

0:07:06 | now |

0:07:07 | the medical box |

0:07:08 | uh computes the function as it's the supposed to do and the and never really that being |

0:07:14 | right |

0:07:14 | a four it is no such my scale but box and what to do in fact is you do some |

0:07:18 | kind of the got be brother but what part six exchange |

0:07:21 | so um the message right |

0:07:24 | so |

0:07:27 | yeah that the world is secure by definition right there is no way of attacking able |

0:07:31 | but in the uh dulles could be applied since you could cheat in the problem |

0:07:34 | and many i what does it mean that you think that this |

0:07:37 | information does not reveal |

0:07:39 | uh anything about the inputs |

0:07:42 | the to formalise these is to say that uh to create that ideal adversary adversity what because a later |

0:07:48 | but leaves in the i don't word |

0:07:50 | and the goal of the similar as or is that by only seeing the input and output of the computation |

0:07:55 | so |

0:07:55 | the |

0:07:57 | by doing but is supposed to do in other word |

0:07:59 | so be able to produce some kind of trust pretty transcript of the problem of that looks the same |

0:08:04 | at these one you |

0:08:05 | and then if you can prove that is uh transcript the are in this transcript the are indistinguishable |

0:08:10 | then say a probabilistic |

0:08:12 | with for problem or T we say that if a have adverse that is a similar in that a word |

0:08:17 | uh such that this uh the output of that were send up output of the symbol with are indistinguishable |

0:08:21 | then we can lower protocol sick Q |

0:08:23 | and need to db does means because the children saying distinguishable and the i don't were the secure but the |

0:08:28 | thing is and then also the real what is secure |

0:08:32 | so there are many uh a kind of a that one can can see |

0:08:36 | uh |

0:08:37 | in the paper in the preceding that are there is much more than this but |

0:08:40 | i think the most important got session is uh about the level of corruption and that you allow |

0:08:44 | so we can can see the passive adversaries that try that that of the brother exactly as it had them |

0:08:49 | but then try to the crypt |

0:08:51 | the what they get |

0:08:53 | then you of active adversary that the do whatever they want and that's the one i'm more calm i most |

0:08:57 | concerned with |

0:08:58 | and then there's summing somewhere in between |

0:09:00 | also the number of corruption option is very important |

0:09:02 | so you can have an honest majority and in this case you can even get perfect security information-theoretic security |

0:09:08 | and then and this problem was a really really efficient |

0:09:11 | in that case is a you can can the as much a key that by the ways the only meaningful |

0:09:16 | uh the and if you look at the but the case right if you into to if two but these |

0:09:20 | are both a on is then |

0:09:21 | there is no need for target |

0:09:24 | so i'm concerned with the design of majority |

0:09:26 | i think about that |

0:09:27 | oh |

0:09:28 | uh |

0:09:30 | and |

0:09:31 | in this C use cryptographic primitives so a but each a is much higher there two |

0:09:36 | to two we dishonest majority |

0:09:38 | then we don't as much |

0:09:40 | okay |

0:09:41 | so that i was that's are uh |

0:09:44 | security more the let's look at some of the techniques that we have |

0:09:49 | so |

0:09:50 | i assume that you're of for that with the concept of a an encryption |

0:09:54 | so a public encryption the is a system or where you have a public in a secret key you have |

0:09:58 | an encryption function |

0:09:59 | that takes uh message put into a separate text |

0:10:01 | and are the caption function that with that of the secret key can retrieve the message from the group is |

0:10:06 | used |

0:10:07 | and what you want this for the encryption to be meaningful look at you want the the decryption to be |

0:10:11 | correct so if you in something a decree the you get the same |

0:10:14 | and also you want been think we should but |

0:10:16 | basically this is that this is a we are |

0:10:20 | this is a version that feeding one line but but signal them saying is that even if you a link |

0:10:24 | point beat i do zero one |

0:10:26 | that was say shouldn't be able to tell you |

0:10:28 | a if and you these encryption of a beat that is you one one give it to that at and |

0:10:32 | just the a you what is this |

0:10:33 | well that was they shouldn't be able to get we'd much more than one out probability |

0:10:37 | so is best are those used to guess |

0:10:39 | so that's what we want from secure |

0:10:41 | but now want to compute on the data right |

0:10:43 | so that would like to have |

0:10:45 | some kind of uh uh we to compute on the data |

0:10:48 | so |

0:10:49 | that's homomorphic norfolk encryption so if you start from two cipher text |

0:10:52 | C one and C two C one is an encryption of fixed one in C two is of is two |

0:10:56 | you would like to have some way of computing on the data |

0:11:00 | you can have an addition you could you but what might want to on addition so you take that use |

0:11:04 | cipher for text |

0:11:05 | you combine them together in some way |

0:11:07 | and then you get then you separate text and now you want then use i've text two |

0:11:11 | to be an encryption of the sum |

0:11:13 | of the original plain text |

0:11:15 | and this is important and that this these addition function is not using the secret key |

0:11:18 | is not the creating summing and encrypting again |

0:11:21 | the addition function is combining the cipher text in the group that the domain |

0:11:24 | to get the |

0:11:26 | to get an use separate text that in the that this um |

0:11:29 | in the where you can define a |

0:11:31 | a multiplication requirement okay |

0:11:34 | so |

0:11:34 | is there anything like that can can something like do exist yeah actually |

0:11:38 | even the |

0:11:40 | we'll build the gum scheme is uh the more we could expect a multiplication |

0:11:45 | and if you want to T scheme uh you have a scheme we have a have a scheme |

0:11:49 | it too |

0:11:49 | uh more time to get to be but we have also them |

0:11:52 | and more recently a people that that uh this covering some creep the system that are |

0:11:57 | additionally digitally on a of peak then you can do one would be vacation |

0:12:00 | so that light to compute a bit more |

0:12:03 | you and could the system is based on padding so G is that be with the lot is |

0:12:07 | and now a couple of years ago a this uh you to break through that is they put "'em" more |

0:12:10 | peak encryption scheme by gender |

0:12:13 | the a bit would think allows use compute on uh everything |

0:12:17 | so |

0:12:17 | for what we can keep she's beautiful it allows you compute everything every function on your |

0:12:22 | on your input i single encryption decryption of those some that and then you can some the data are more |

0:12:26 | divided it you can be any function |

0:12:28 | and the we and this was the map it was good that it seem to be uh absolutely impractical but |

0:12:34 | at or that |

0:12:35 | i don't think at nine but the this uh |

0:12:38 | ragged get the for the put a pick encryption is based on lattices is is |

0:12:41 | so i that this is just a a real the points |

0:12:43 | is a S is that discrete creates group of a a vector space |

0:12:48 | uh and you can have a basis of these the of this space so we can have this model on |

0:12:52 | of these long one |

0:12:53 | and the might one is a good one because it allows you to compute the all the points we a |

0:12:57 | big one it's either they're to to to solve some problem |

0:13:00 | so one of the problem that is at to solve in uh in these this if you only about a |

0:13:04 | long base |

0:13:05 | is to find the "'cause" is that the problem so if i give it is red point |

0:13:08 | and ask you which point is close you are not able to do that |

0:13:12 | and you can make an encryption all of these so you take a lot this point X and you are |

0:13:15 | down or vector |

0:13:16 | E |

0:13:17 | and this is a good encryption if you have a secret key so if you have a good luck is |

0:13:20 | days you can |

0:13:21 | recover big big point and find their or |

0:13:24 | if you have a only the public you can not do that |

0:13:27 | and now you can in |

0:13:28 | in this error vector you can encode or beat so you can uh the find is that are back to |

0:13:33 | to be two times some |

0:13:35 | random random that and then you put the a bit in one of the position of the vector i |

0:13:40 | now if you have to back to of this power men some them together |

0:13:43 | well |

0:13:43 | that you at this point and you like this point |

0:13:46 | there are some to gather and also of this to be uh good pitching comes there and then basically you |

0:13:50 | have an addition model |

0:13:52 | so this system is the additive T or more |

0:13:56 | is a problem that that are blows so you can only do a limited amount of operation you can't keep |

0:14:00 | adding a a a uh for a |

0:14:03 | and and other thing to i'm is is that these vectors |

0:14:06 | and not only that those you know that this but you can also look at them as polynomials |

0:14:09 | well no male small or the |

0:14:11 | so |

0:14:12 | we just in on it |

0:14:13 | and then you seven a multiplication operation |

0:14:15 | that no less in the same way it gives you that if you multiply to to cipher text to get |

0:14:20 | uh uh and the recreational also in the in the thing thing |

0:14:25 | uh so as this though do that so we can only do a limited number of a patient |

0:14:29 | but for uh these gentry found is a great way of uh |

0:14:34 | using them a mapping properties |

0:14:35 | black too uh the query |

0:14:38 | a a for a text |

0:14:39 | in to the crypt of them are typically inside the cipher text |

0:14:42 | so we can the crypt the i a separate X to of the better and get that new cipher for |

0:14:47 | text |

0:14:48 | with uh with a smaller |

0:14:50 | and not gonna tell you more about these all good |

0:14:52 | uh |

0:14:53 | and then you have that the uh so last week at you okay of that all that that act that |

0:14:56 | this scheme is the implemented it |

0:14:58 | and it doesn't take as long as we would have like that so this is a a reasonable level of |

0:15:02 | security |

0:15:03 | and the can uh compute in a of degrees to hundred |

0:15:06 | and the every multiplication cost the zero point one second |

0:15:09 | is not as bad as we thought |

0:15:11 | a of that these if you want to do the for them more pick one |

0:15:14 | then we takes much more and then every multiplication takes three mean used to do |

0:15:19 | uh is that is an you technology but it's |

0:15:22 | it's that and uh someone is actually by think of the for that so |

0:15:25 | the |

0:15:26 | following |

0:15:27 | but i think i want to talk about this to but the computation |

0:15:30 | uh so the more uh a stand up about |

0:15:33 | and i'm looking at a job at P with active the corruption |

0:15:37 | we that one of the parties crap |

0:15:39 | so the first but because solution was from two years ago and they could evaluate that the gets a segment |

0:15:43 | in a recent work of me with some of my quarters |

0:15:46 | we but that to twenty thousand gates a second |

0:15:48 | but it doesn't gets the second is uh a more try |

0:15:53 | so i'll do we do these uh |

0:15:55 | very briefly it's an T base probable |

0:15:57 | and the a be this task but then each have believed to be really expensive because they quite public key |

0:16:02 | technology |

0:16:03 | uh uh C a target piece fast because it only uses a symmetric |

0:16:08 | but as you know the results are or something "'cause" i bit encryption right if you want to send a |

0:16:12 | a a a when you open a necessary connection what to do is that you send |

0:16:15 | and he S it key using a say because i say is bad and then uh a S is good |

0:16:20 | in the same way we can do the same with the or be that's that |

0:16:22 | so we can do a a a a a little bit of real a to has but using public key |

0:16:26 | cryptography |

0:16:27 | and then you can extend them using only the symmetric key operation |

0:16:32 | and that for all based on but a cheap because they only basically only but asymptotically they only require |

0:16:37 | a symmetric uh cryptography |

0:16:38 | and that's very P |

0:16:40 | so and a bin is task good an object of this way a where you have a |

0:16:43 | uh a a the which two messages is the time one |

0:16:46 | and i with the receiver that to this uh think matt and that's and signal |

0:16:50 | well that's and than anything about sigma and that is that's and and other message |

0:16:54 | this is the same as a very small computation so on a that's is actually a a a uh one |

0:16:58 | bit computation |

0:17:00 | and if and combine them get together to get a big computation |

0:17:04 | we need in these the work was to find a way to uh preserve the security also when |

0:17:09 | uh uh the the the these crap that but i'm not gonna do anything about that |

0:17:13 | because is looking about of me so really gonna you about the uh uh i one good i wanna leave |

0:17:18 | space for question |

0:17:19 | so |

0:17:19 | the message of these is the following techniques for a P C are getting faster and faster genetic techniques for |

0:17:24 | N P C |

0:17:25 | so don't be afraid of using a a you know of writing your |

0:17:28 | uh signal processing out if you know |

0:17:30 | uh as a sec with because we can compute a circuits it's fast and fast |

0:17:35 | so twenty thousand that will and gates per second the that we can do now maybe few years we will |

0:17:39 | be able to emulate late that one mhz secure process |

0:17:43 | a it's going fast |

0:17:45 | and the maybe to was uh to the for a signal processing but then that's what one of the challenge |

0:17:50 | i think is the most interesting for a processing is that |

0:17:53 | uh in cryptography we want everybody to be every bit to be protected because we can about the privacy of |

0:17:57 | every bit |

0:17:57 | but a signal processing have a lot of data maybe not that of this need to be protected uh |

0:18:03 | the same way |

0:18:04 | and that a it could be interesting to find some reasonable security to model |

0:18:08 | two |

0:18:08 | to actually model this fact that the you know not all of the signal should be protecting the same way |

0:18:13 | steve we can F's |

0:18:14 | some reasonable sick using the finish on |

0:18:16 | to capture this problem |

0:18:17 | thank you to much |

0:18:24 | time for a couple of questions |

0:18:27 | yes |

0:18:37 | thank very much for this very nice |

0:18:39 | station |

0:18:40 | fast |

0:18:41 | i i have a small question about your lost more |

0:18:44 | really |

0:18:45 | um we we are dealing with |

0:18:47 | know |

0:18:47 | is |

0:18:48 | but |

0:18:49 | so many of |

0:18:49 | like |

0:18:50 | like it |

0:18:51 | so yeah image |

0:18:52 | you that that maybe not every bit is |

0:18:54 | really important |

0:18:56 | so for example if we want to in the this system using a i |

0:18:59 | crypto the system |

0:19:00 | we always use at thousand bits |

0:19:04 | key |

0:19:05 | so do you think that maybe if we use a hundreds |

0:19:07 | it's |

0:19:08 | a |

0:19:09 | but you okay |

0:19:10 | or or how can be apply |

0:19:13 | so |

0:19:13 | it's not so for us |

0:19:15 | to i will eat the security because we are application orient people what your a over |

0:19:19 | so what you thing about that |

0:19:21 | so actually |

0:19:23 | is is a is gonna be some worse because as you you can not use the so |

0:19:28 | when it would but you can do multiplication in with a lot of bits five you have you have this |

0:19:31 | big secure the model and that this be one thousand bits |

0:19:35 | they you can pack all them information inside the |

0:19:37 | in on seven X and then you can do operation would big the |

0:19:42 | a not of the at the same time |

0:19:43 | uh used so you only care about on the be so you make the keys is smaller of course you |

0:19:47 | can do that because of of i think is not secure anymore |

0:19:49 | right |

0:19:50 | so |

0:19:52 | the problem and that is that and that's not gonna be a to uh uh with when the time goes |

0:19:56 | because in ten years from now you still gonna be looking at maybe image job you know maybe is they |

0:20:00 | want to the computation on |

0:20:01 | thirty it's |

0:20:02 | but in ten is from now but a keys should be eight thousand bits |

0:20:06 | so this your security requirements is going well the computation is not going so yeah |

0:20:11 | the the fact the now we can pick other information in yeah and that's meaningful |

0:20:14 | it's kind of an not the fact that of the the the the the fact that you know right now |

0:20:17 | it's more or less the same |

0:20:19 | but it's uh but is not gonna scowl we well in the future |

0:20:22 | so mm |

0:20:24 | so think that actually |

0:20:26 | you know a just where |

0:20:27 | this security to by means there and the we should be couple of the security by me that |

0:20:31 | and the computation so from once in from one hand you have the the size of a computation maybe be |

0:20:36 | to to it is enough |

0:20:37 | from the other hand of the C parameter is going uh |

0:20:40 | uh fast |

0:20:41 | that you think should be the couple and that's i think but |

0:20:43 | uh |

0:20:45 | are other process at doing not not only |

0:20:50 | yeah |

0:20:54 | we'll to but that's |

0:20:56 | you can explain as in layman's terms what the gender group she |

0:20:59 | does how why does it |

0:21:01 | so i to me |

0:21:03 | the problem was a talking about it's of a is a but up is a V and then to be |

0:21:07 | from this you have to a choose lies that i was i but from them |

0:21:11 | so i should |

0:21:11 | thank that |

0:21:12 | uh uh this paper is spend so it's a score the implementing gentry E the system and it's a a |

0:21:18 | you you can understand that |

0:21:20 | i think a it's a is not too hard |

0:21:22 | so i well it's a problem of fig |

0:21:25 | at the P Z the |

0:21:28 | so it's a it's basically doing |

0:21:30 | uh multiplication polynomials |

0:21:32 | well i that's a key or that some of the study |

0:21:34 | uh and then you have to understand that this what action back i think the signal processing community |

0:21:39 | uh understands |

0:21:40 | but and the sense that this is but then |

0:21:42 | many other the committees is because you use and lot is this and the coding data |

0:21:47 | some because of that the problem is not |

0:21:49 | two five i i way from you know the coding problem |

0:21:52 | so |

0:21:53 | i would recommend it to me that paper |

0:21:56 | very quick question |

0:22:01 | high uh just reminding in the first question usually in signal processing we are basically doing operation on |

0:22:09 | samples that's |

0:22:10 | can be let's say and can you on eight bits |

0:22:13 | yeah excel is and kind in a bit |

0:22:16 | that's it's using you new |

0:22:18 | crypt the system how many be i need to presents that simple now |

0:22:22 | so uh |

0:22:24 | in a in just to map in in in my work |

0:22:27 | you know not for my work uh basically have a bit that's an expansion factor of |

0:22:31 | uh |

0:22:32 | well and bits that's say like that |

0:22:33 | so uh the security is uh |

0:22:35 | i every a bit for able to so the was are |

0:22:41 | so i of it is presented as one bit |

0:22:44 | and then we have a make an information to mac |

0:22:46 | so i from a synthetic make uh |

0:22:48 | if T be it's one and that twenty bits |

0:22:50 | so that an expansion factor that is not the lot about i the will this uh problem of X a |

0:22:55 | uh the |

0:22:56 | well |

0:22:57 | we can take it is applying but the it's it's even big |

0:23:00 | it's in but then than this but yeah you have a the the the the that |

0:23:03 | but |

0:23:04 | yeah that's a C at beats wonder bit |

0:23:07 | but that's is that the minimum the security uh use the one beats become one hundred bits yeah such set |

0:23:11 | and that yeah that's a huge overhead for us are there any can of |

0:23:16 | research in trying to regroup |

0:23:18 | for as |

0:23:19 | it would be re groping samples together a but being able to do operation on |

0:23:24 | parts of the be uh on segments of the beats |

0:23:27 | with is in the encrypted so you can do that that really it is not this work is another piece |

0:23:31 | of work well i do i have the computation |

0:23:33 | well i have the mac and where i uh okay we'd numbers model not be well the number so maybe |

0:23:38 | arithmetic computation of but number of one hundred twenty bits it's for the sense and the mac is the same |

0:23:43 | size in that case have an a of factor of two |

0:23:45 | i guess but uh the and uh uh then you need to use a if we can keep some basic |

0:23:49 | you but it too |

0:23:51 | yeah we've think it up right |

0:23:54 | alright |

0:23:55 | thank you |