En la infraestructura pública de clave —PKI, por sus siglas en inglés—, que dos certificados se necesitan para poder completar una transacción de cifrado o de firmado de forma autenticada.

Un certificado válido permite autenticar a una cuenta, pero la aplicación deniega el acceso al recurso solicitado. ¿Es contradictorio?

En la infraestructura pública de clave —PKI, por sus siglas en inglés—, tal y como se trabajó en el aula, cualquier persona usuaria puede validar un certificado si tiene acceso al certificado de la autoridad que lo emitió y firmó. Eso se hace validando la firma del certificado con la clave pública contenida en el certificado de la autoridad.

La técnica del código de autenticación de mensaje —MAC por sus siglas en inglés— pertenece a la dimensión de la seguridad de la información denominada «autenticación» porque protege la integridad de la información.

El programa GnuPG, que implementa el paradigma de gestión de la identidad de red de confianza, le permite a cada sujeto gestionar el conjunto de identidades y claves asociadas que custodia.

¿Por qué una lista de revocación de certificados está firmada con la clave privada correspondiente a la clave pública solicitada?

Se recibe una clave pública por un canal no autenticado y se verifica correctamente una firma con ella. ¿Qué puede concluirse por sí solo?

A un consultorio llegan pacientes con una tasa de cuatro pacientes por hora, si la llegada de pacientes sigue una distribución Poisson, responda las siguientes preguntas:

<!-- /* Font Definitions */ @font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:-536870145 1107305727 0 0 415 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman",serif; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES; mso-fareast-language:ES;}.MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; font-size:11.0pt; mso-ansi-font-size:11.0pt; mso-bidi-font-size:11.0pt; font-family:"Calibri",sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-ansi-language:ES; mso-fareast-language:EN-US;}.MsoPapDefault {mso-style-type:export-only; margin-bottom:10.0pt; line-height:115%;}@page WordSection1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;}div.WordSection1 {page:WordSection1;}-->

<!-- /* Font Definitions */ @font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:-536870145 1107305727 0 0 415 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman",serif; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES; mso-fareast-language:ES;}p.MsoListParagraph, li.MsoListParagraph, div.MsoListParagraph {mso-style-priority:34; mso-style-unhide:no; mso-style-qformat:yes; margin-top:0cm; margin-right:0cm; margin-bottom:0cm; margin-left:36.0pt; margin-bottom:.0001pt; mso-add-space:auto; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman",serif; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES; mso-fareast-language:ES;}p.MsoListParagraphCxSpFirst, li.MsoListParagraphCxSpFirst, div.MsoListParagraphCxSpFirst {mso-style-priority:34; mso-style-unhide:no; mso-style-qformat:yes; mso-style-type:export-only; margin-top:0cm; margin-right:0cm; margin-bottom:0cm; margin-left:36.0pt; margin-bottom:.0001pt; mso-add-space:auto; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman",serif; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES; mso-fareast-language:ES;}p.MsoListParagraphCxSpMiddle, li.MsoListParagraphCxSpMiddle, div.MsoListParagraphCxSpMiddle {mso-style-priority:34; mso-style-unhide:no; mso-style-qformat:yes; mso-style-type:export-only; margin-top:0cm; margin-right:0cm; margin-bottom:0cm; margin-left:36.0pt; margin-bottom:.0001pt; mso-add-space:auto; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman",serif; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES; mso-fareast-language:ES;}p.MsoListParagraphCxSpLast, li.MsoListParagraphCxSpLast, div.MsoListParagraphCxSpLast {mso-style-priority:34; mso-style-unhide:no; mso-style-qformat:yes; mso-style-type:export-only; margin-top:0cm; margin-right:0cm; margin-bottom:0cm; margin-left:36.0pt; margin-bottom:.0001pt; mso-add-space:auto; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman",serif; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES; mso-fareast-language:ES;}.MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; font-size:11.0pt; mso-ansi-font-size:11.0pt; mso-bidi-font-size:11.0pt; font-family:"Calibri",sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-ansi-language:ES; mso-fareast-language:EN-US;}.MsoPapDefault {mso-style-type:export-only; margin-bottom:10.0pt; line-height:115%;}@page WordSection1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;}div.WordSection1 {page:WordSection1;} /* List Definitions */ @list l0 {mso-list-id:1428891971; mso-list-type:hybrid; mso-list-template-ids:941415364 201981969 201981977 201981979 201981967 201981977 201981979 201981967 201981977 201981979;}@list l0:level1 {mso-level-text:"%1\)"; mso-level-tab-stop:none; mso-level-number-position:left; margin-left:18.0pt; text-indent:-18.0pt;}@list l0:level2 {mso-level-number-format:alpha-lower; mso-level-tab-stop:none; mso-level-number-position:left; text-indent:-18.0pt;}@list l0:level3 {mso-level-number-format:roman-lower; mso-level-tab-stop:none; mso-level-number-position:right; text-indent:-9.0pt;}@list l0:level4 {mso-level-tab-stop:none; mso-level-number-position:left; text-indent:-18.0pt;}@list l0:level5 {mso-level-number-format:alpha-lower; mso-level-tab-stop:none; mso-level-number-position:left; text-indent:-18.0pt;}@list l0:level6 {mso-level-number-format:roman-lower; mso-level-tab-stop:none; mso-level-number-position:right; text-indent:-9.0pt;}@list l0:level7 {mso-level-tab-stop:none; mso-level-number-position:left; text-indent:-18.0pt;}@list l0:level8 {mso-level-number-format:alpha-lower; mso-level-tab-stop:none; mso-level-number-position:left; text-indent:-18.0pt;}@list l0:level9 {mso-level-number-format:roman-lower; mso-level-tab-stop:none; mso-level-number-position:right; text-indent:-9.0pt;}ol {margin-bottom:0cm;}ul {margin-bottom:0cm;}-->

<!-- /* Font Definitions */ @font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:-536870145 1107305727 0 0 415 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman",serif; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES; mso-fareast-language:ES;}p.MsoListParagraph, li.MsoListParagraph, div.MsoListParagraph {mso-style-priority:34; mso-style-unhide:no; mso-style-qformat:yes; margin-top:0cm; margin-right:0cm; margin-bottom:0cm; margin-left:36.0pt; margin-bottom:.0001pt; mso-add-space:auto; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman",serif; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES; mso-fareast-language:ES;}p.MsoListParagraphCxSpFirst, li.MsoListParagraphCxSpFirst, div.MsoListParagraphCxSpFirst {mso-style-priority:34; mso-style-unhide:no; mso-style-qformat:yes; mso-style-type:export-only; margin-top:0cm; margin-right:0cm; margin-bottom:0cm; margin-left:36.0pt; margin-bottom:.0001pt; mso-add-space:auto; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman",serif; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES; mso-fareast-language:ES;}p.MsoListParagraphCxSpMiddle, li.MsoListParagraphCxSpMiddle, div.MsoListParagraphCxSpMiddle {mso-style-priority:34; mso-style-unhide:no; mso-style-qformat:yes; mso-style-type:export-only; margin-top:0cm; margin-right:0cm; margin-bottom:0cm; margin-left:36.0pt; margin-bottom:.0001pt; mso-add-space:auto; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman",serif; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES; mso-fareast-language:ES;}p.MsoListParagraphCxSpLast, li.MsoListParagraphCxSpLast, div.MsoListParagraphCxSpLast {mso-style-priority:34; mso-style-unhide:no; mso-style-qformat:yes; mso-style-type:export-only; margin-top:0cm; margin-right:0cm; margin-bottom:0cm; margin-left:36.0pt; margin-bottom:.0001pt; mso-add-space:auto; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman",serif; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES; mso-fareast-language:ES;}.MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; font-size:11.0pt; mso-ansi-font-size:11.0pt; mso-bidi-font-size:11.0pt; font-family:"Calibri",sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-ansi-language:ES; mso-fareast-language:EN-US;}.MsoPapDefault {mso-style-type:export-only; margin-bottom:10.0pt; line-height:115%;}@page WordSection1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;}div.WordSection1 {page:WordSection1;} /* List Definitions */ @list l0 {mso-list-id:1428891971; mso-list-type:hybrid; mso-list-template-ids:941415364 201981969 201981977 201981979 201981967 201981977 201981979 201981967 201981977 201981979;}@list l0:level1 {mso-level-text:"%1\)"; mso-level-tab-stop:none; mso-level-number-position:left; margin-left:18.0pt; text-indent:-18.0pt;}@list l0:level2 {mso-level-number-format:alpha-lower; mso-level-tab-stop:none; mso-level-number-position:left; text-indent:-18.0pt;}@list l0:level3 {mso-level-number-format:roman-lower; mso-level-tab-stop:none; mso-level-number-position:right; text-indent:-9.0pt;}@list l0:level4 {mso-level-tab-stop:none; mso-level-number-position:left; text-indent:-18.0pt;}@list l0:level5 {mso-level-number-format:alpha-lower; mso-level-tab-stop:none; mso-level-number-position:left; text-indent:-18.0pt;}@list l0:level6 {mso-level-number-format:roman-lower; mso-level-tab-stop:none; mso-level-number-position:right; text-indent:-9.0pt;}@list l0:level7 {mso-level-tab-stop:none; mso-level-number-position:left; text-indent:-18.0pt;}@list l0:level8 {mso-level-number-format:alpha-lower; mso-level-tab-stop:none; mso-level-number-position:left; text-indent:-18.0pt;}@list l0:level9 {mso-level-number-format:roman-lower; mso-level-tab-stop:none; mso-level-number-position:right; text-indent:-9.0pt;}ol {margin-bottom:0cm;}ul {margin-bottom:0cm;}-->

Un motor d’un cotxe ens dóna 100 CV.   Si el rendiment és del 32,5 %, quina és la potència consumida en watts?