Dr Kevin Atighehchi \u2013 Laboratoire GREYC (Groupe de Recherche en Informatique, Image, Automatique et Instrumentation de Caen)<\/p>\n
Quand: lundi 12 mars 2018, \u00e0 15h00 Titre :<\/strong> \u00ab\u00a0Quelques contributions \u00e0 l’efficacit\u00e9 des m\u00e9canismes cryptographiques\u00a0\u00bb<\/p>\n R\u00e9sum\u00e9 :<\/strong> Courte bio :<\/strong> Dr Kevin Atighehchi \u2013 Laboratoire GREYC (Groupe de Recherche en Informatique, Image, Automatique et Instrumentation de Caen) Quand: lundi 12 mars 2018, \u00e0 15h00 O\u00f9 : salle G10, \u00e0 T\u00e9l\u00e9com SudParis (Evry) Titre : \u00ab\u00a0Quelques contributions \u00e0 l’efficacit\u00e9 des m\u00e9canismes cryptographiques\u00a0\u00bb R\u00e9sum\u00e9 : Les besoins constants d\u2019innovation en mati\u00e8re de performances et d\u2019\u00e9conomie des ressources […]<\/p>\n","protected":false},"author":1,"featured_media":997,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"ocean_post_layout":"","ocean_both_sidebars_style":"","ocean_both_sidebars_content_width":0,"ocean_both_sidebars_sidebars_width":0,"ocean_sidebar":"","ocean_second_sidebar":"","ocean_disable_margins":"enable","ocean_add_body_class":"","ocean_shortcode_before_top_bar":"","ocean_shortcode_after_top_bar":"","ocean_shortcode_before_header":"","ocean_shortcode_after_header":"","ocean_has_shortcode":"","ocean_shortcode_after_title":"","ocean_shortcode_before_footer_widgets":"","ocean_shortcode_after_footer_widgets":"","ocean_shortcode_before_footer_bottom":"","ocean_shortcode_after_footer_bottom":"","ocean_display_top_bar":"default","ocean_display_header":"default","ocean_header_style":"","ocean_center_header_left_menu":"","ocean_custom_header_template":"","ocean_custom_logo":0,"ocean_custom_retina_logo":0,"ocean_custom_logo_max_width":0,"ocean_custom_logo_tablet_max_width":0,"ocean_custom_logo_mobile_max_width":0,"ocean_custom_logo_max_height":0,"ocean_custom_logo_tablet_max_height":0,"ocean_custom_logo_mobile_max_height":0,"ocean_header_custom_menu":"","ocean_menu_typo_font_family":"","ocean_menu_typo_font_subset":"","ocean_menu_typo_font_size":0,"ocean_menu_typo_font_size_tablet":0,"ocean_menu_typo_font_size_mobile":0,"ocean_menu_typo_font_size_unit":"px","ocean_menu_typo_font_weight":"","ocean_menu_typo_font_weight_tablet":"","ocean_menu_typo_font_weight_mobile":"","ocean_menu_typo_transform":"","ocean_menu_typo_transform_tablet":"","ocean_menu_typo_transform_mobile":"","ocean_menu_typo_line_height":0,"ocean_menu_typo_line_height_tablet":0,"ocean_menu_typo_line_height_mobile":0,"ocean_menu_typo_line_height_unit":"","ocean_menu_typo_spacing":0,"ocean_menu_typo_spacing_tablet":0,"ocean_menu_typo_spacing_mobile":0,"ocean_menu_typo_spacing_unit":"","ocean_menu_link_color":"","ocean_menu_link_color_hover":"","ocean_menu_link_color_active":"","ocean_menu_link_background":"","ocean_menu_link_hover_background":"","ocean_menu_link_active_background":"","ocean_menu_social_links_bg":"","ocean_menu_social_hover_links_bg":"","ocean_menu_social_links_color":"","ocean_menu_social_hover_links_color":"","ocean_disable_title":"default","ocean_disable_heading":"default","ocean_post_title":"","ocean_post_subheading":"","ocean_post_title_style":"","ocean_post_title_background_color":"","ocean_post_title_background":0,"ocean_post_title_bg_image_position":"","ocean_post_title_bg_image_attachment":"","ocean_post_title_bg_image_repeat":"","ocean_post_title_bg_image_size":"","ocean_post_title_height":0,"ocean_post_title_bg_overlay":0.5,"ocean_post_title_bg_overlay_color":"","ocean_disable_breadcrumbs":"default","ocean_breadcrumbs_color":"","ocean_breadcrumbs_separator_color":"","ocean_breadcrumbs_links_color":"","ocean_breadcrumbs_links_hover_color":"","ocean_display_footer_widgets":"default","ocean_display_footer_bottom":"default","ocean_custom_footer_template":"","ocean_post_oembed":"","ocean_post_self_hosted_media":"","ocean_post_video_embed":"","ocean_link_format":"","ocean_link_format_target":"self","ocean_quote_format":"","ocean_quote_format_link":"post","ocean_gallery_link_images":"on","ocean_gallery_id":[],"footnotes":""},"categories":[316],"tags":[],"class_list":["post-998","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-seminaires-r3s-2018-fr","entry","has-media"],"_links":{"self":[{"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/posts\/998","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/comments?post=998"}],"version-history":[{"count":1,"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/posts\/998\/revisions"}],"predecessor-version":[{"id":1553,"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/posts\/998\/revisions\/1553"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/media\/997"}],"wp:attachment":[{"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/media?parent=998"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/categories?post=998"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/tags?post=998"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\nO\u00f9 : salle G10, \u00e0 T\u00e9l\u00e9com SudParis (Evry)<\/strong><\/p>\n
\nLes besoins constants d\u2019innovation en mati\u00e8re de performances et d\u2019\u00e9conomie des ressources nous poussent \u00e0 effectuer des optimisations dans la conception et l\u2019utilisation des outils cryptographiques. Quelques contributions seront pr\u00e9sent\u00e9es sur plusieurs aspects : les algorithmes cryptographiques parall\u00e8les, les algorithmes cryptographiques incr\u00e9mentaux et les dictionnaires authentifi\u00e9s. Dans le cadre de la cryptographie parall\u00e8le, nous nous int\u00e9ressons aux fonctions de hachage bas\u00e9es sur des arbres. Nous montrons quelles structures arborescentes utiliser pour atteindre un temps d\u2019ex\u00e9cution optimum avec un nombre de processeurs que nous cherchons \u00e0 minimiser dans un second temps. Les syst\u00e8mes cryptographiques incr\u00e9mentaux permettent, lorsque nous modifions des documents, de mettre \u00e0 jour leurs formes cryptographiques efficacement. Nous montrons que les syst\u00e8mes actuels restreignent beaucoup trop les modifications possibles et introduisons de nouveaux algorithmes s\u2019appuyant sur ces derniers, utilis\u00e9s comme des boites noires, afin de rendre possible une large gamme de modifications aux documents tout en conservant une propri\u00e9t\u00e9 de secret de l\u2019op\u00e9ration effectu\u00e9e. Notre int\u00e9r\u00eat porte ensuite sur les dictionnaires authentifi\u00e9s, utilis\u00e9s pour authentifier les r\u00e9ponses aux requ\u00eates des utilisateurs sur un dictionnaire, en leur fournissant une preuve d\u2019authenticit\u00e9 pour chaque r\u00e9ponse. Nous nous focalisons sur des syst\u00e8mes bas\u00e9s sur des arbres de hachage et proposons une solution pour amoindrir leur principal inconv\u00e9nient, celui de la taille des preuves.<\/p>\n
\nAuparavant ATER \u00e0 l’Universit\u00e9 d’Aix-Marseille (AMU), j’effectue actuellement un Post-Doc dans l’\u00e9quipe Mon\u00e9tique & Biom\u00e9trie du Groupe de Recherche en Informatique, Image, Automatique et Instrumentation de Caen (GREYC). Mes th\u00e9matiques de recherche s’articulent autour de la cryptographie appliqu\u00e9e aux syst\u00e8mes biom\u00e9triques, la cryptographie l\u00e9g\u00e8re pour l’Internet des Objets (IoT) et l’utilisation de technologies \u00e9mergentes (Blockchain et Trusted Execution Environment) dans les protocoles de s\u00e9curit\u00e9. Mes autres domaines d’int\u00e9r\u00eat concernent le parall\u00e9lisme des primitives cryptographiques et l’optimisation des op\u00e9rations arithm\u00e9tiques dans les corps finis.
\nMa th\u00e8se a \u00e9t\u00e9 effectu\u00e9e au sein de l’Institut de Math\u00e9matiques de Marseille (I2M) et a \u00e9t\u00e9 soutenue \u00e0 l’Universit\u00e9 d’Aix-Marseille en 2015. Mon sujet de th\u00e8se, qui portait sur l’efficacit\u00e9 des m\u00e9canismes cryptographiques, m’a amen\u00e9 \u00e0 aborder les th\u00e8mes de la cryptographie incr\u00e9mentale, des dictionnaires authentifi\u00e9s et du parall\u00e9lisme des fonctions de hachage.<\/p>\n","protected":false},"excerpt":{"rendered":"