Cryptography
Cryptography is an indispensable tool for protecting information in computer systems.Take This Course Free
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Cryptography is an indispensable tool for protecting information in computer systems. This course explains the inner workings of cryptographic primitives and how to correctly use them. Students will learn how to reason about the security of cryptographic constructions and how to apply this knowledge to real-world applications. The course begins with a detailed discussion of how two parties who have a shared secret key can communicate securely when a powerful adversary eavesdrops and tampers with traffic. We will examine many deployed protocols and analyze mistakes in existing systems. The second half of the course discusses public-key techniques that let two or more parties generate a shared secret key. We will cover the relevant number theory and discuss public-key encryption and basic key-exchange. Throughout the course students will be exposed to many exciting open problems in the field.
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Cryptography is an indispensable tool for protecting information in computer systems.
Stanford University Lectures for iPhone Application Development
Nr | Query | Error | Affected | Num. rows | Took (ms) |
---|---|---|---|---|---|
1 | SELECT `Advertiser`.`id`, `Advertiser`.`title`, `Advertiser`.`description`, `Advertiser`.`link`, `Advertiser`.`button_title`, `Advertiser`.`logo`, `Advertiser`.`logo_blob`, `Advertiser`.`status`, `Advertiser`.`created`, `Advertiser`.`modified` FROM `1337iot`.`advertisers` AS `Advertiser` WHERE `status` = 1 ORDER BY rand() ASC LIMIT 1 | 0 | 0 | 1 | |
2 | SELECT `Configuration`.`id`, `Configuration`.`heading`, `Configuration`.`default_header`, `Configuration`.`value`, `Configuration`.`created`, `Configuration`.`modified` FROM `1337iot`.`configurations` AS `Configuration` WHERE 1 = 1 | 28 | 28 | 0 | |
3 | SELECT `Cmspages`.`name`, `Cmspages`.`seourl` FROM `1337iot`.`cmspages` AS `Cmspages` WHERE `Cmspages`.`showinfooter` = '1' AND `Cmspages`.`status` = '1' ORDER BY `Cmspages`.`name` ASC | 5 | 5 | 0 | |
4 | SELECT `UserViewCourse`.`id`, `UserViewCourse`.`user_id` FROM `1337iot`.`user_view_courses` AS `UserViewCourse` WHERE `UserViewCourse`.`course_id` = 52 | 10 | 10 | 0 | |
5 | SELECT distinct(`UserViewCourse`.`course_id`), `Course`.`id`, `Course`.`title`, `Course`.`subtitle`, `Course`.`price`, `Course`.`coverimage`, `Course`.`user_id`, (select count(*) as countstudent from user_learning_courses as UserLearningCourse where `UserLearningCourse`.`course_id` = `UserViewCourse`.`course_id`) AS `UserViewCourse__students`, (select avg(rating) rating from course_reviews CourseReview where `CourseReview`.`course_id` = `UserViewCourse`.`course_id`) AS `UserViewCourse__review`, (select concat(`Userdetail`.`first_name`,' ',`Userdetail`.`last_name`) as name from userdetails as Userdetail where `Userdetail`.`user_id` = `Course`.`user_id`) AS `UserViewCourse__name` FROM `1337iot`.`user_view_courses` AS `UserViewCourse` LEFT JOIN `1337iot`.`users` AS `User` ON (`UserViewCourse`.`user_id` = `User`.`id`) LEFT JOIN `1337iot`.`courses` AS `Course` ON (`UserViewCourse`.`course_id` = `Course`.`id`) WHERE `UserViewCourse`.`user_id` in (24036,24359,22320,24810,26148,28430,187,31817,25887,23538) LIMIT 3 | 3 | 3 | 1 | |
6 | SELECT `CourseReview`.`rating`, `CourseReview`.`Created`, `CourseReview`.`review_text`, `Userdetail`.`first_name`, `Userdetail`.`last_name`, `Userdetail`.`image`, `Userdetail`.`user_id`, (select avg(rating) from course_reviews CourseReview where `CourseReview`.`course_id` =52) AS `CourseReview__avgrating` FROM `1337iot`.`course_reviews` AS `CourseReview` LEFT JOIN `1337iot`.`userdetails` AS `Userdetail` ON (`Userdetail`.`user_id` = `CourseReview`.`user_id`) WHERE `CourseReview`.`course_id` = 52 LIMIT 3 | 0 | 0 | 0 | |
7 | SELECT COUNT(*) AS `count` FROM `1337iot`.`course_reviews` AS `CourseReview` LEFT JOIN `1337iot`.`users` AS `User` ON (`CourseReview`.`user_id` = `User`.`id`) LEFT JOIN `1337iot`.`courses` AS `Course` ON (`CourseReview`.`course_id` = `Course`.`id`) WHERE `CourseReview`.`course_id` = 52 | 1 | 1 | 0 | |
8 | SELECT `CourseSection`.`id`, `CourseSection`.`course_id`, `CourseSection`.`heading`, `CourseSection`.`section_index`, `CourseSection`.`prev`, `CourseSection`.`created`, `CourseSection`.`modified` FROM `1337iot`.`course_sections` AS `CourseSection` WHERE `CourseSection`.`course_id` = 52 | 12 | 12 | 0 | |
9 | SELECT `CourseLecture`.`id`, `CourseLecture`.`course_id`, `CourseLecture`.`course_section_id`, `CourseLecture`.`heading`, `CourseLecture`.`course_description`, `CourseLecture`.`content`, `CourseLecture`.`content_type`, `CourseLecture`.`content_title`, `CourseLecture`.`content_external_link`, `CourseLecture`.`content_source`, `CourseLecture`.`supplimentary_material`, `CourseLecture`.`lecture_index`, `CourseLecture`.`prev`, `CourseLecture`.`live_status`, `CourseLecture`.`file1_upload`, `CourseLecture`.`file2_upload`, `CourseLecture`.`created`, `CourseLecture`.`modified` FROM `1337iot`.`course_lectures` AS `CourseLecture` WHERE `CourseLecture`.`course_section_id` IN (73, 75, 76, 77, 78, 80, 82, 85, 86, 87, 88, 89) | 65 | 65 | 0 | |
10 | SELECT `CourseQuiz`.`id`, `CourseQuiz`.`course_section_id`, `CourseQuiz`.`course_lecture_id`, `CourseQuiz`.`heading`, `CourseQuiz`.`content`, `CourseQuiz`.`publish`, `CourseQuiz`.`created`, `CourseQuiz`.`modified` FROM `1337iot`.`course_quizzes` AS `CourseQuiz` WHERE `CourseQuiz`.`course_section_id` IN (73, 75, 76, 77, 78, 80, 82, 85, 86, 87, 88, 89) | 0 | 0 | 0 | |
11 | SELECT `Course`.`id`, `Course`.`user_id`, `Course`.`category_id`, `Course`.`language_id`, `Course`.`instruction_level_id`, `Course`.`title`, `Course`.`subtitle`, `Course`.`keywords`, `Course`.`summary`, `Course`.`lincence_logo`, `Course`.`lincence_url`, `Course`.`source_title`, `Course`.`source_url`, `Course`.`coverimage`, `Course`.`promovideo`, `Course`.`visibility`, `Course`.`pricetype`, `Course`.`price`, `Course`.`privacy_type`, `Course`.`publishstatus`, `Course`.`status`, `Course`.`created`, `Course`.`modified`, `InstructionLevel`.`id`, `InstructionLevel`.`title`, `InstructionLevel`.`created`, `InstructionLevel`.`modified` FROM `1337iot`.`courses` AS `Course` LEFT JOIN `1337iot`.`instruction_levels` AS `InstructionLevel` ON (`Course`.`instruction_level_id` = `InstructionLevel`.`id`) WHERE `Course`.`id` = 52 AND `Course`.`status` = '1' LIMIT 1 | 1 | 1 | 0 | |
12 | SELECT `CourseAudience`.`id`, `CourseAudience`.`course_id`, `CourseAudience`.`title`, `CourseAudience`.`created`, `CourseAudience`.`modified` FROM `1337iot`.`course_audience` AS `CourseAudience` WHERE `CourseAudience`.`course_id` = (52) | 0 | 0 | 0 | |
13 | SELECT `CourseGoal`.`id`, `CourseGoal`.`course_id`, `CourseGoal`.`title`, `CourseGoal`.`created`, `CourseGoal`.`modified` FROM `1337iot`.`course_goals` AS `CourseGoal` WHERE `CourseGoal`.`course_id` = (52) | 0 | 0 | 0 | |
14 | SELECT `CourseRequirement`.`id`, `CourseRequirement`.`course_id`, `CourseRequirement`.`title`, `CourseRequirement`.`created`, `CourseRequirement`.`modified` FROM `1337iot`.`course_requirements` AS `CourseRequirement` WHERE `CourseRequirement`.`course_id` = (52) | 0 | 0 | 0 | |
15 | SELECT `Userdetail`.*, `User`.`id` FROM `1337iot`.`users` AS `User` LEFT JOIN `1337iot`.`userdetails` AS `Userdetail` ON (`Userdetail`.`user_id` = `User`.`id`) WHERE `User`.`id` = 18 LIMIT 1 | 1 | 1 | 0 | |
16 | SELECT `Course`.`id`, `Course`.`title`, `Course`.`subtitle`, `Course`.`coverimage`, `Course`.`summary`, `Course`.`price`, `Course`.`user_id`, (select count(*) as countstudent from user_learning_courses as UserLearningCourse where `UserLearningCourse`.`course_id` = `Course`.`id`) AS `Course__students`, (select avg(rating) from course_reviews CourseReview where `CourseReview`.`course_id` = `Course`.`id`) AS `Course__avgrating`, (select concat(`Userdetail`.`first_name`,' ',`Userdetail`.`last_name`) as name from userdetails as Userdetail where `Userdetail`.`user_id` = `Course`.`user_id`) AS `Course__name` FROM `1337iot`.`courses` AS `Course` WHERE `Course`.`user_id` = 18 AND `Course`.`publishstatus` = 'Publish' ORDER BY (select count(*) as countstudent from user_learning_courses as UserLearningCourse where `UserLearningCourse`.`course_id` = `Course`.`id`) desc LIMIT 2 | 2 | 2 | 0 | |
17 | SELECT COUNT(*) AS `count` FROM `1337iot`.`courses` AS `Course` LEFT JOIN `1337iot`.`users` AS `User` ON (`Course`.`user_id` = `User`.`id`) LEFT JOIN `1337iot`.`languages` AS `Language` ON (`Course`.`language_id` = `Language`.`id`) LEFT JOIN `1337iot`.`instruction_levels` AS `InstructionLevel` ON (`Course`.`instruction_level_id` = `InstructionLevel`.`id`) WHERE `Course`.`user_id` = 18 AND `Course`.`publishstatus` = 'Publish' | 1 | 1 | 0 | |
18 | SELECT `Userdetail`.`user_id`, `Userdetail`.`first_name`, `Userdetail`.`last_name`, `Userdetail`.`image` FROM `1337iot`.`user_learning_courses` AS `UserLearningCourse` Inner JOIN `1337iot`.`bundles` AS `Bundle` ON (`Bundle`.`status` = 1 AND `UserLearningCourse`.`bundle_id` = `Bundle`.`id`) LEFT JOIN `1337iot`.`userdetails` AS `Userdetail` ON (`UserLearningCourse`.`user_id` = `Userdetail`.`id`) WHERE `UserLearningCourse`.`course_id` = 52 LIMIT 14 | 14 | 14 | 0 | |
19 | SELECT COUNT(*) AS `count` FROM `1337iot`.`user_learning_courses` AS `UserLearningCourse` LEFT JOIN `1337iot`.`users` AS `User` ON (`UserLearningCourse`.`user_id` = `User`.`id`) LEFT JOIN `1337iot`.`courses` AS `Course` ON (`UserLearningCourse`.`course_id` = `Course`.`id`) Inner JOIN `1337iot`.`bundles` AS `Bundle` ON (`Bundle`.`status` = 1 AND `UserLearningCourse`.`bundle_id` = `Bundle`.`id`) WHERE `UserLearningCourse`.`course_id` = 52 | 1 | 1 | 1 | |
20 | SELECT `Course`.`id`, `Course`.`user_id`, `Course`.`category_id`, `Course`.`language_id`, `Course`.`instruction_level_id`, `Course`.`title`, `Course`.`subtitle`, `Course`.`keywords`, `Course`.`summary`, `Course`.`lincence_logo`, `Course`.`lincence_url`, `Course`.`source_title`, `Course`.`source_url`, `Course`.`coverimage`, `Course`.`promovideo`, `Course`.`visibility`, `Course`.`pricetype`, `Course`.`price`, `Course`.`privacy_type`, `Course`.`publishstatus`, `Course`.`status`, `Course`.`created`, `Course`.`modified`, (select count(*) as countstudent from user_learning_courses as UserLearningCourse where `UserLearningCourse`.`course_id` = `Course`.`id`) AS `Course__students`, (select avg(rating) from course_reviews CourseReview where `CourseReview`.`course_id` = `Course`.`id`) AS `Course__avgrating`, (select concat(`Userdetail`.`first_name`,' ',`Userdetail`.`last_name`) as name from userdetails as Userdetail where `Userdetail`.`user_id` = `Course`.`user_id`) AS `Course__name` FROM `1337iot`.`courses` AS `Course` WHERE `Course`.`id` = 52 AND `Course`.`publishstatus` = 'Publish' LIMIT 1 | 1 | 1 | 0 | |
21 | SELECT `UserLearningCourse`.`id`, `UserLearningCourse`.`user_id`, `UserLearningCourse`.`course_id`, `UserLearningCourse`.`completed`, `UserLearningCourse`.`created`, `UserLearningCourse`.`bundle_id`, `UserLearningCourse`.`modified`, `UserLearningCourse`.`payerid`, `User`.`id`, `User`.`fbid`, `User`.`username`, `User`.`password`, `User`.`remembertoken`, `User`.`loginfrom`, `User`.`status`, `User`.`passwordstatus`, `User`.`newsletter`, `User`.`profiletype`, `User`.`created`, `User`.`modified`, `Course`.`id`, `Course`.`user_id`, `Course`.`category_id`, `Course`.`language_id`, `Course`.`instruction_level_id`, `Course`.`title`, `Course`.`subtitle`, `Course`.`keywords`, `Course`.`summary`, `Course`.`lincence_logo`, `Course`.`lincence_url`, `Course`.`source_title`, `Course`.`source_url`, `Course`.`coverimage`, `Course`.`promovideo`, `Course`.`visibility`, `Course`.`pricetype`, `Course`.`price`, `Course`.`privacy_type`, `Course`.`publishstatus`, `Course`.`status`, `Course`.`created`, `Course`.`modified`, (select count(*) as countstudent from user_learning_courses as UserLearningCourse where `UserLearningCourse`.`course_id` = `Course`.`id`) AS `Course__students`, (select avg(rating) from course_reviews CourseReview where `CourseReview`.`course_id` = `Course`.`id`) AS `Course__avgrating`, (select concat(`Userdetail`.`first_name`,' ',`Userdetail`.`last_name`) as name from userdetails as Userdetail where `Userdetail`.`user_id` = `Course`.`user_id`) AS `Course__name`, `Bundle`.`id`, `Bundle`.`title`, `Bundle`.`is_expired`, `Bundle`.`status`, `Bundle`.`expired_on`, `Bundle`.`created`, `Bundle`.`modified` FROM `1337iot`.`user_learning_courses` AS `UserLearningCourse` LEFT JOIN `1337iot`.`users` AS `User` ON (`UserLearningCourse`.`user_id` = `User`.`id`) LEFT JOIN `1337iot`.`courses` AS `Course` ON (`UserLearningCourse`.`course_id` = `Course`.`id`) Inner JOIN `1337iot`.`bundles` AS `Bundle` ON (`Bundle`.`status` = 1 AND `UserLearningCourse`.`bundle_id` = `Bundle`.`id`) WHERE `UserLearningCourse`.`user_id` IS NULL AND `UserLearningCourse`.`course_id` = 52 LIMIT 1 | 0 | 0 | 1 | |
22 | SELECT `CourseUserQuestion`.`id`, `CourseUserQuestion`.`user_id`, `CourseUserQuestion`.`course_id`, `CourseUserQuestion`.`course_lecture_id`, `CourseUserQuestion`.`heading`, `CourseUserQuestion`.`question`, `CourseUserQuestion`.`created`, `CourseUserQuestion`.`modified`, (select `Userdetail`.`first_name` from userdetails Userdetail where `Userdetail`.`user_id` = `CourseUserQuestion`.`user_id`) AS `CourseUserQuestion__firstname`, (select `Userdetail`.`last_name` from userdetails Userdetail where `Userdetail`.`user_id` = `CourseUserQuestion`.`user_id`) AS `CourseUserQuestion__lastname`, (select lecture_index from course_lectures where `course_lectures`.`id` = `CourseUserQuestion`.`course_lecture_id`) AS `CourseUserQuestion__lectureindex`, `User`.`id`, `User`.`fbid`, `User`.`username`, `User`.`password`, `User`.`remembertoken`, `User`.`loginfrom`, `User`.`status`, `User`.`passwordstatus`, `User`.`newsletter`, `User`.`profiletype`, `User`.`created`, `User`.`modified`, `Course`.`id`, `Course`.`user_id`, `Course`.`category_id`, `Course`.`language_id`, `Course`.`instruction_level_id`, `Course`.`title`, `Course`.`subtitle`, `Course`.`keywords`, `Course`.`summary`, `Course`.`lincence_logo`, `Course`.`lincence_url`, `Course`.`source_title`, `Course`.`source_url`, `Course`.`coverimage`, `Course`.`promovideo`, `Course`.`visibility`, `Course`.`pricetype`, `Course`.`price`, `Course`.`privacy_type`, `Course`.`publishstatus`, `Course`.`status`, `Course`.`created`, `Course`.`modified`, (select count(*) as countstudent from user_learning_courses as UserLearningCourse where `UserLearningCourse`.`course_id` = `Course`.`id`) AS `Course__students`, (select avg(rating) from course_reviews CourseReview where `CourseReview`.`course_id` = `Course`.`id`) AS `Course__avgrating`, (select concat(`Userdetail`.`first_name`,' ',`Userdetail`.`last_name`) as name from userdetails as Userdetail where `Userdetail`.`user_id` = `Course`.`user_id`) AS `Course__name`, `CourseLecture`.`id`, `CourseLecture`.`course_id`, `CourseLecture`.`course_section_id`, `CourseLecture`.`heading`, `CourseLecture`.`course_description`, `CourseLecture`.`content`, `CourseLecture`.`content_type`, `CourseLecture`.`content_title`, `CourseLecture`.`content_external_link`, `CourseLecture`.`content_source`, `CourseLecture`.`supplimentary_material`, `CourseLecture`.`lecture_index`, `CourseLecture`.`prev`, `CourseLecture`.`live_status`, `CourseLecture`.`file1_upload`, `CourseLecture`.`file2_upload`, `CourseLecture`.`created`, `CourseLecture`.`modified` FROM `1337iot`.`course_user_questions` AS `CourseUserQuestion` LEFT JOIN `1337iot`.`users` AS `User` ON (`CourseUserQuestion`.`user_id` = `User`.`id`) LEFT JOIN `1337iot`.`courses` AS `Course` ON (`CourseUserQuestion`.`course_id` = `Course`.`id`) LEFT JOIN `1337iot`.`course_lectures` AS `CourseLecture` ON (`CourseUserQuestion`.`course_lecture_id` = `CourseLecture`.`id`) WHERE `CourseUserQuestion`.`course_id` = 52 AND `CourseUserQuestion`.`user_id` IS NULL ORDER BY `CourseUserQuestion`.`created` desc | 0 | 0 | 1 |