{"id":23731,"date":"2022-07-06T00:00:00","date_gmt":"2022-07-06T00:00:00","guid":{"rendered":"https:\/\/www.mailgun.com\/blog\/controle-connexion-tls\/"},"modified":"2026-09-16T16:56:23","modified_gmt":"2026-09-16T16:56:23","slug":"controle-connexion-tls","status":"publish","type":"blog","link":"https:\/\/www.mailgun.com\/fr\/blog\/product\/controle-connexion-tls\/","title":{"rendered":"Les bases du TLS\u00a0: qu&rsquo;est-ce que le contr\u00f4le de connexion TLS\u00a0?"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">What would you discuss over a secure line? Some James Bondian plans?<\/p>\n\n<p class=\"wp-block-paragraph\">Chances are, you\u2019d more likely be doing something mundane, like scheduling your next meeting or online shopping. Whether or not you\u2019re aware of it, encryption is already part of your email communication, and every email you send is essentially like chatting on a secure line.<\/p>\n\n<p class=\"wp-block-paragraph\">Even though there are a variety of encryption protocols, most email clients, like Gmail, have made Transport Layer Security (TLS) encryption an essential part of their protocols. But what is TLS, and why is it important for email campaign managers to fine-tune their TLS connection control? We\u2019ll dig into that now.<\/p>\n\r\n    <nav data-content-type=\"longform\" class=\"toc-block longform-spacings px-5 py-6 px-md-6 px-lg-7 py-md-7 bg-light fs-sm rounded-lg\" aria-labelledby=\"toc-title-6878\"><p class=\"h5 m-0\" id=\"toc-title-6878\">Table des mati\u00e8res<\/p><div class=\"d-flex mt-3\"><div class=\"w-auto fw-bold text-accent d-flex me-2\">01<\/div><div class=\"d-flex flex-column\"><a class=\"fw-bold scrollme link-body-color text-accent\" href=\"#why-do-i-need-to-encrypt-my-emails\">Why do I need to encrypt my emails?<\/a><\/div><\/div><div class=\"d-flex mt-3\"><div class=\"w-auto fw-bold text-accent d-flex me-2\">02<\/div><div class=\"d-flex flex-column\"><a class=\"fw-bold scrollme link-body-color text-accent\" href=\"#what-is-tls-and-why-is-it-important\">What is TLS and why is it important?<\/a><a class=\"scrollme link-body-color\" href=\"#whats-the-difference-between-tls-ssl-and-http\">What\u2019s the difference between TLS, SSL, and HTTP?<\/a><a class=\"scrollme link-body-color\" href=\"#what-are-the-three-main-things-the-tls-protocol-enables\">What are the three main things the TLS protocol enables?<\/a><\/div><\/div><div class=\"d-flex mt-3\"><div class=\"w-auto fw-bold text-accent d-flex me-2\">03<\/div><div class=\"d-flex flex-column\"><a class=\"fw-bold scrollme link-body-color text-accent\" href=\"#why-should-businesses-use-the-tls-protocol-and-what-are-the-different-levels-of-ssl-tls-security-certifications\">Why should businesses use the TLS protocol, and what are the different levels of SSL\/TLS security certifications?<\/a><\/div><\/div><div class=\"d-flex mt-3\"><div class=\"w-auto fw-bold text-accent d-flex me-2\">04<\/div><div class=\"d-flex flex-column\"><a class=\"fw-bold scrollme link-body-color text-accent\" href=\"#whats-the-tls-handshake-and-how-does-it-work\">What\u2019s the TLS handshake and how does it work?<\/a><\/div><\/div><div class=\"d-flex mt-3\"><div class=\"w-auto fw-bold text-accent d-flex me-2\">05<\/div><div class=\"d-flex flex-column\"><a class=\"fw-bold scrollme link-body-color text-accent\" href=\"#how-do-i-customize-email-connection-settings-with-mailgun\">How do I customize email connection settings with Mailgun?<\/a><a class=\"scrollme link-body-color\" href=\"#how-do-i-ensure-messages-are-delivered-over-a-tls-connection\">How do I ensure messages are delivered over a TLS connection?<\/a><a class=\"scrollme link-body-color\" href=\"#how-do-i-enable-or-disable-certificate-verification\">How do I enable or disable certificate verification?<\/a><a class=\"scrollme link-body-color\" href=\"#how-do-i-see-the-details-on-how-my-email-was-delivered\">How do I see the details on how my email was delivered?<\/a><\/div><\/div><div class=\"d-flex mt-3\"><div class=\"w-auto fw-bold text-accent d-flex me-2\">06<\/div><div class=\"d-flex flex-column\"><a class=\"fw-bold scrollme link-body-color text-accent\" href=\"#what-are-some-examples-of-sending-emails-with-custom-connection-settings-in-mailgun\">What are some examples of sending emails with custom connection settings in Mailgun?<\/a><a class=\"scrollme link-body-color\" href=\"#how-do-i-send-a-single-email-with-custom-connection-settings\">How do I send a single email with custom connection settings?<\/a><a class=\"scrollme link-body-color\" href=\"#how-do-i-configure-a-sending-domain-to-deliver-emails-with-custom-connection-settings\">How do I configure a sending domain to deliver emails with custom connection settings?<\/a><a class=\"scrollme link-body-color\" href=\"#how-can-i-check-my-custom-connection-configuration\">How can I check my custom connection configuration?<\/a><\/div><\/div><div class=\"d-flex mt-3\"><div class=\"w-auto fw-bold text-accent d-flex me-2\">07<\/div><div class=\"d-flex flex-column\"><a class=\"fw-bold scrollme link-body-color text-accent\" href=\"#wrapping-up\">Wrapping up<\/a><\/div><\/div><\/nav>\n<h2 class=\"wp-block-heading\">Why do I need to encrypt my emails?<\/h2>\n\n<p class=\"wp-block-paragraph\">Let\u2019s start with some basics. You probably know that sending without encryption is risky, but what could actually happen if your message wasn&rsquo;t encrypted? Here are some common cybersecurity problems you\u2019d face if you sent and received emails without encryption:<\/p>\n\n<ul class=\"wp-block-list\">\n<li><b>Message tampering: <\/b>Encryption protects the transmission of secure data and enables the recipient to see if the message was modified in transit.<\/li>\n\n\n\n<li><b>Eavesdropping: <\/b>Anyone can capture and read your emails as they travel through the network. Without encryption, you\u2019d have no privacy. In more technical terms, this prevents man-in-the-middle attacks.<\/li>\n\n\n\n<li><b>Privacy invasion: <\/b>Unencrypted emails also transmit sensitive information, like your IP address, your city, or even your street address, which could also compromise your privacy.<\/li>\n\n\n\n<li><b>Identity theft:<\/b>Hackers could potentially capture your login details if you aren\u2019t accessing your email server or website over an encrypted connection.<\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\">Below, we\u2019ll learn about TLS and how to work it into your email routine.<\/p>\n\n<h2 class=\"wp-block-heading\">What is TLS and why is it important?<\/h2>\n\n<p class=\"wp-block-paragraph\">TLS is a cryptographic protocol that provides end-to-end security of data sent between web applications and web servers over the internet. It encrypts the connection through which data is sent over the internet, preventing third parties from seeing your data, like passwords, credit card numbers, and personal correspondence. In short, sending a message over the TLS protocol is like talking openly over a secured phone line.<\/p>\n\n<p class=\"wp-block-paragraph\">Before diving into what exactly is TLS, let\u2019s start with a brief history lesson.<\/p>\n\n<p class=\"wp-block-paragraph\">The Internet Engineering Task Force (IETF) defined TLS 1.0 in 1999. Before that, the Secure Socket Layer (SSL) was the standard encryption protocol for the internet. Currently, SSL certificates just mean that a particular website is using some sort of cryptographic protocol to verify their ownership of the domain, a role which TLS fulfills. In fact, the SSL certificate should be more appropriately called a TLS certificate since it uses TLS, not SSL.<\/p>\n\n<p class=\"wp-block-paragraph\">Don\u2019t worry \u2013 the TLS used by modern systems isn\u2019t actually from 1999. <a href=\"https:\/\/www.mailgun.com\/fr\/blog\/product\/obsolescence-des-versions-1-0-et-1-1-de-tls\/\" target=\"_tabs\" rel=\"noopener noreferrer\">TLS versions 1.0 and 1.1<\/a> were deprecated in 2020 and are no longer used by most email service providers. Today,\u00a0 <b>TLS 1.3 is the current protocol version and TLS 1.2 continues to be supported.<\/b><\/p>\n\n<h3 class=\"wp-block-heading\">What\u2019s the difference between TLS, SSL, and HTTP?<\/h3>\n\n<p class=\"wp-block-paragraph\">TLS is the encryption protocol for securing most of the internet, and its easy to spot which sites are or aren\u2019t compliant. Take a look at the URL for this article and notice how it starts with \u201chttps\u201d and has a closed gray padlock icon. Connections secured by TLS are labeled <a href=\"https:\/\/www.mailgun.com\/fr\/blog\/it-and-engineering\/cours-intensif-http\/\" target=\"_tabs\" rel=\"noopener noreferrer\">Hypertext Transfer Protocol Secure (HTTPS) instead of just HTTP<\/a>.<\/p>\n\n<h3 class=\"wp-block-heading\">What are the three main things the TLS protocol enables?<\/h3>\n\n<p class=\"wp-block-paragraph\">Ancient history aside, TLS is important because there are three main things the protocol enables:<\/p>\n\n<ul class=\"wp-block-list\">\n<li><b>Encryption: <\/b>TLS secures the data in your emails from third parties.<\/li>\n\n\n\n<li><b>Authentication:<\/b> TLS authenticates the server (and optionally, the client) from which a message is being sent.<\/li>\n\n\n\n<li><b>Integrity:<\/b> TLS verifies the data integrity to check it\u2019s free from forgery and tampering.<\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\">All of these work together to ensure a secure end-to-end email experience for both you and your subscribers.<\/p>\n\n<h2 class=\"wp-block-heading\">Why should businesses use the TLS protocol, and what are the different levels of SSL\/TLS security certifications?<\/h2>\n\n<p class=\"wp-block-paragraph\">Constant vigilance is the key to preventing data breaches and other cybersecurity attacks. Use TLS encryption to <b>strengthen your business\u2019s data security<\/b> over the web and in email marketing campaigns and in transactional emails. Most browsers will also alert users if your website or email communications aren&rsquo;t secure, which could lead to lower web traffic and could make your brand look less legitimate.<\/p>\n\n<p class=\"wp-block-paragraph\">Although TLS provides adequate security for communications, your business may need extended authentication to provide increased protection for sensitive data. In these cases, your organization can opt for business-level authenticationTLS\/SSL certificates, which come in the following three security levels:<\/p>\n\n<ul class=\"wp-block-list\">\n<li><b>Domain validation certificates:<\/b> This is the most basic TLS\/SSL certificate, which requires you to prove that you control the domain name you\u2019ve supplied. Keep in mind that the domain validation certificate doesn\u2019t confirm the identity of you or your business.<\/li>\n\n\n\n<li><b>Organization validation certificates:<\/b> This certificate builds off of the domain validation certificate. Not only does it require you to prove that you control the domain name you\u2019ve supplied, but it also requires you to prove that your company is legally registered as a business. We recommend this for public-facing sites that collect data from your users.<\/li>\n\n\n\n<li><b>Extended validation certificates:<\/b> This is the most secure TLS\/SSL certificate. In addition to proving ownership of your domain name and establishing the legality of your company, these certificates include additional verification steps designed to protect data from tampering.<\/li>\n<\/ul>\n\n<h2 class=\"wp-block-heading\">What\u2019s the TLS handshake and how does it work?<\/h2>\n\n<p class=\"wp-block-paragraph\">Now that we know what TLS is, let\u2019s go over how exactly the TLS protocol works to secure your online communication.<\/p>\n\n<p class=\"wp-block-paragraph\">Modern TLS, including versions 1.2 and 1.3, use two types of cryptography to maintain high performance along with reliable security:<\/p>\n\n<ul class=\"wp-block-list\">\n<li><b>Symmetriccryptography: <\/b>This encrypts data using a secret key that has been shared with both the sender and the recipient. Keep in mind this secret key should be at least 128 bits in length.<\/li>\n\n\n\n<li><b>Asymmetriccryptography: <\/b>This encrypts data with key pairs made up of a private key and a public key. Asymmetric cryptography is more secure than just using a secret key, but it also demands a greater bandwidth since the recommended minimum key length is 1024 bits.<\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\">TLS uses asymmetric encryption to establish a secure session between a client and a server. Then, it uses symmetric encryption to exchange data within the secured session. This process is defined as the TLS handshake: the process by which communication between a client and server is established and defined.<\/p>\n\n<p class=\"wp-block-paragraph\">In other words, the TLS handshake process is a negotiation between the email client or web browser that sends your message and the web server it interacts. The two sit down and acknowledge each other, authenticate each other\u2019s identities, designate encryption algorithms, and agree upon secure session keys.<\/p>\n\n<p class=\"wp-block-paragraph\">Here\u2019s how a TLS 1.3 handshake works:<\/p>\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" width=\"617\" height=\"599\" src=\"https:\/\/www.mailgun.com\/wp-content\/uploads\/2022\/07\/image1.webp\" alt=\"Diagramme de s\u00e9quence d&apos;un handshake TLS 1.3 montrant l&apos;\u00e9change de cl\u00e9s, les param\u00e8tres du serveur, l&apos;authentification et les donn\u00e9es d&apos;application\" class=\"wp-image-6342\" srcset=\"https:\/\/www.mailgun.com\/wp-content\/uploads\/2022\/07\/image1.webp 617w, https:\/\/www.mailgun.com\/wp-content\/uploads\/2022\/07\/image1-300x291.webp 300w\" sizes=\"(max-width: 617px) 100vw, 617px\" \/><figcaption class=\"wp-element-caption\"><em>TLS 1.3 Handshake diagram (<\/em><a href=\"https:\/\/www.ibm.com\/docs\/en\/sdk-java-technology\/8?topic=handshake-tls-13-protocol\"><em><u>Source<\/u><\/em><\/a><em>)<\/em><\/figcaption><\/figure>\n\n<ol class=\"wp-block-list\">\n<li>The client contacts the server with a \u201cclient hello\u201d message. This message alerts the server to the client\u2019s TLS version to check for compatibility. It also shares a key and the client\u2019s cipher suites. From there, the key is used to encrypt and decrypt messages.<\/li>\n\n\n\n<li>The server responds to the client\u2019s message and shared key with a \u201cserver hello\u201d message. This message shares a key in response and indicates the server\u2019s supported versions. The server may also request a TLS\/SSL certificate and verifies it.<\/li>\n\n\n\n<li>The client receives the certificate and verifies it, completing the client-side portion of the TLS handshake.<\/li>\n<\/ol>\n\n<p class=\"wp-block-paragraph\">Now, the client can communicate with the server using a HTTP protocol.<\/p>\n\n<h2 class=\"wp-block-heading\">How do I customize email connection settings with Mailgun?<\/h2>\n\n<p class=\"wp-block-paragraph\">Mailgun implements an opportunistic TLS by default. Whenever we connect to a mail exchange (MX) server, we first try to upgrade the connection to a TLS connection to deliver your messages. However, if it\u2019s not offered or some kind of error occurs while establishing the connection (like an invalid certificate, for example), we use a <a href=\"https:\/\/www.mailgun.com\/fr\/fonctionnalites\/serveur-smtp\/\" target=\"_tabs\" rel=\"noopener noreferrer\">plaintext SMTP connection<\/a> instead.<\/p>\n\n<p class=\"wp-block-paragraph\">We\u2019ve also implemented ways for you to customize your connection settings for message delivery by:<\/p>\n\n<ul class=\"wp-block-list\">\n<li>Exposing a new flag to ensure messages are only delivered over a TLS connection.<\/li>\n\n\n\n<li>Allowing you to enable or disable certificate verification.<\/li>\n\n\n\n<li>Exposing the MX server we delivered the message to, the TLS state of the connection, and whether or not we verified the certificate during delivery in our Logs.<\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\">Let\u2019s dive into each of these below.<\/p>\n\n<h3 class=\"wp-block-heading\">How do I ensure messages are delivered over a TLS connection?<\/h3>\n\n<p class=\"wp-block-paragraph\">We\u2019ve exposed a new flag \u2013 <code>require tls \u2013<\/code> that allows you to control how your messages are delivered. Set this flag to <code>True<\/code> to require that the message must be sent over a TLS connection. If a TLS connection can\u2019t be established, Mailgun won\u2019t deliver the message.<\/p>\n\n<p class=\"wp-block-paragraph\">The default for <code>require tls<\/code> is <code>False<\/code>, which means we will try to use a TLS connection but will still deliver your email over a plaintext SMTP connection if we can\u2019t use TLS.<\/p>\n\n<h3 class=\"wp-block-heading\">How do I enable or disable certificate verification?<\/h3>\n\n<p class=\"wp-block-paragraph\">The new flag <code>skip verification<\/code> allows you to enable or disable certificate and hostname verification. If set to <code>True<\/code>, Mailgun won\u2019t verify the certificate and hostname when trying to establish a TLS connection. Instead, Mailgun will accept any certificate during delivery.<\/p>\n\n<p class=\"wp-block-paragraph\">By default, <code>skip verification<\/code> is set to <code>False<\/code>, which means that we\u2019ll try to verify the certificate and if we can\u2019t, a TLS connection won\u2019t be established.<\/p>\n\n<h3 class=\"wp-block-heading\">How do I see the details on how my email was delivered?<\/h3>\n\n<p class=\"wp-block-paragraph\">We\u2019ve exposed three additional flags in our Logs which provide insight into how your email was delivered. First, navigate to the <code>delivery-status<\/code> document. Then, look for the following flags:<\/p>\n\n<ul class=\"wp-block-list\">\n<li><code>tls<\/code>: This flag indicates whether or not we used a TLS connection to deliver your message.<\/li>\n\n\n\n<li><code>certificate-verified<\/code>: This flag indicates whether or not we verified the certificate when delivering your message.<\/li>\n\n\n\n<li><code>mx-host<\/code>: This indicates the MX server we connected to deliver your message.<\/li>\n<\/ul>\n\n<h2 class=\"wp-block-heading\">What are some examples of sending emails with custom connection settings in Mailgun?<\/h2>\n\n<p class=\"wp-block-paragraph\">Let\u2019s put the flags above into practice. In this section, we\u2019ll go through examples of sending emails with custom connection settings in Mailgun, including:<\/p>\n\n<ul class=\"wp-block-list\">\n<li>Sending a single message with custom connections.<\/li>\n\n\n\n<li>Configuring an entire sending domain to deliver messages with custom connections.<\/li>\n\n\n\n<li>Checking your configuration.<\/li>\n<\/ul>\n\n<h3 class=\"wp-block-heading\">How do I send a single email with custom connection settings?<\/h3>\n\n<p class=\"wp-block-paragraph\">If you have a single message you\u2019d like to deliver with custom connection settings, you can use the code below:<\/p>\n    <div data-content-type=\"longform\" class=\"code-snippet longform-spacings rounded-lg overflow-hidden shadow \" data-count=\"1\">\r\n        <ul class=\"nav nav-buttons code-snippet__tabs longform-except position-relative d-flex gap-2 flex-wrap p-3\" role=\"tablist\">\r\n\r\n                            \r\n                    \r\n                        <li class=\"nav-item\" role=\"presentation\">\r\n                            <button class=\"nav-link active\" data-bs-toggle=\"tab\" data-bs-target=\"#code_0\" type=\"button\" role=\"tab\" aria-controls=\"code_0\" aria-selected=\"true\">\r\n                                Shell                            <\/button>\r\n                        <\/li>\r\n\r\n                    \r\n                            \r\n        <\/ul>\r\n        <div class=\"code-snippet__tab-content tab-content\">\r\n\r\n                            \r\n                    <div class=\"tab-pane show active\" id=\"code_0\" role=\"tabpanel\" aria-labelledby=\"code_0\">\r\n                        <div class=\"code-snippet__code-wrapper\">\r\n                            <div class=\"nav nav-buttons code-snippet__copy-wrapper\">\r\n                                <button type=\"button\" class=\"nav-link code-snippet__copy\" data-clipboard-target=\"#code_0_content\" data-clipboard-label=\"Copier dans le presse-papiers\" data-clipboard-success-label=\"Copi\u00e9\u00a0!\" data-clipboard-error-label=\"Impossible de copier\" data-tooltip=\"Copier dans le presse-papiers\" data-tooltip-placement=\"left\" role=\"tooltip\" aria-label=\"Copier dans le presse-papiers\">\r\n                                    <svg class=\"code-snippet__copy-icon code-snippet__copy-icon--default\" width=\"24\" height=\"24\" aria-hidden=\"true\" data-url=\"https:\/\/www.mailgun.com\/wp-content\/plugins\/sinch-core\/assets\/icons\/sinch\/file-stack.svg\"><\/svg>\r\n                                    <svg class=\"code-snippet__copy-icon code-snippet__copy-icon--success\" width=\"24\" height=\"24\" aria-hidden=\"true\" data-url=\"https:\/\/www.mailgun.com\/wp-content\/plugins\/sinch-core\/assets\/icons\/sinch\/badge-check.svg\"><\/svg>\r\n                                <\/button>\r\n                            <\/div>\r\n                            <pre class=\"w-100 h-100 m-0 line-numbers language-shell\">\r\n                                <code id=\"code_0_content\" class=\"language-shell\">\r\n\r\n                                    curl -sk --user &#039;api:API_KEY&#039;   \r\n    https:\/\/api.mailgun.net\/v3\/DOMAIN_NAME\/messages \r\n    -F from=&#039;foo@example.com&#039; \r\n    -F to=&#039;bar@example.com&#039; \r\n    -F subject=&#039;Hello&#039; \r\n    -F text=&#039;Testing some Mailgun awesomness!&#039; \r\n    -F o:require-tls=&#039;false&#039; \r\n    -F o:skip-verification=&#039;true&#039;\r\n                                <\/code>\r\n                            <\/pre>\r\n                        <\/div>\r\n                    <\/div>\r\n                                    <\/div>\r\n    <\/div>\r\n\n<h3 class=\"wp-block-heading\">How do I configure a sending domain to deliver emails with custom connection settings?<\/h3>\n\n<p class=\"wp-block-paragraph\">If you\u2019d like to configure an entire sending domain to deliver messages in a particular manner, check out the code below:<\/p>\n    <div data-content-type=\"longform\" class=\"code-snippet longform-spacings rounded-lg overflow-hidden shadow \" data-count=\"1\">\r\n        <ul class=\"nav nav-buttons code-snippet__tabs longform-except position-relative d-flex gap-2 flex-wrap p-3\" role=\"tablist\">\r\n\r\n                            \r\n                    \r\n                        <li class=\"nav-item\" role=\"presentation\">\r\n                            <button class=\"nav-link active\" data-bs-toggle=\"tab\" data-bs-target=\"#code_0\" type=\"button\" role=\"tab\" aria-controls=\"code_0\" aria-selected=\"true\">\r\n                                Shell                            <\/button>\r\n                        <\/li>\r\n\r\n                    \r\n                            \r\n        <\/ul>\r\n        <div class=\"code-snippet__tab-content tab-content\">\r\n\r\n                            \r\n                    <div class=\"tab-pane show active\" id=\"code_0\" role=\"tabpanel\" aria-labelledby=\"code_0\">\r\n                        <div class=\"code-snippet__code-wrapper\">\r\n                            <div class=\"nav nav-buttons code-snippet__copy-wrapper\">\r\n                                <button type=\"button\" class=\"nav-link code-snippet__copy\" data-clipboard-target=\"#code_0_content\" data-clipboard-label=\"Copier dans le presse-papiers\" data-clipboard-success-label=\"Copi\u00e9\u00a0!\" data-clipboard-error-label=\"Impossible de copier\" data-tooltip=\"Copier dans le presse-papiers\" data-tooltip-placement=\"left\" role=\"tooltip\" aria-label=\"Copier dans le presse-papiers\">\r\n                                    <svg class=\"code-snippet__copy-icon code-snippet__copy-icon--default\" width=\"24\" height=\"24\" aria-hidden=\"true\" data-url=\"https:\/\/www.mailgun.com\/wp-content\/plugins\/sinch-core\/assets\/icons\/sinch\/file-stack.svg\"><\/svg>\r\n                                    <svg class=\"code-snippet__copy-icon code-snippet__copy-icon--success\" width=\"24\" height=\"24\" aria-hidden=\"true\" data-url=\"https:\/\/www.mailgun.com\/wp-content\/plugins\/sinch-core\/assets\/icons\/sinch\/badge-check.svg\"><\/svg>\r\n                                <\/button>\r\n                            <\/div>\r\n                            <pre class=\"w-100 h-100 m-0 line-numbers language-shell\">\r\n                                <code id=\"code_0_content\" class=\"language-shell\">\r\n\r\n                                    curl -sk --user &#039;api:API_KEY&#039;   \r\n    -X PUT https:\/\/api.mailgun.net\/v3\/domains\/DOMAIN_NAME\/connection \r\n    -F require_tls=&#039;false&#039; \r\n    -F skip_verification=&#039;true&#039;\r\n                                <\/code>\r\n                            <\/pre>\r\n                        <\/div>\r\n                    <\/div>\r\n                                    <\/div>\r\n    <\/div>\r\n\n<p class=\"wp-block-paragraph\">Alternatively, you can also change your domain settings for any specific domain via the Mailgun control panel. To do so, navigate over to your sending tab and scroll down to `domain settings`, from there you can change your TLS settings under the `security` section.<\/p>\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" width=\"1000\" height=\"150\" src=\"https:\/\/www.mailgun.com\/wp-content\/uploads\/2022\/07\/image2.webp\" alt=\"Param\u00e8tres de s\u00e9curit\u00e9 : connexion TLS d\u00e9finie sur Opportuniste et v\u00e9rification de certificat d\u00e9finie sur Requise\" class=\"wp-image-6347\" srcset=\"https:\/\/www.mailgun.com\/wp-content\/uploads\/2022\/07\/image2.webp 1000w, https:\/\/www.mailgun.com\/wp-content\/uploads\/2022\/07\/image2-300x45.webp 300w, https:\/\/www.mailgun.com\/wp-content\/uploads\/2022\/07\/image2-768x115.webp 768w\" sizes=\"(max-width: 1000px) 100vw, 1000px\" \/><\/figure>\n\n<h3 class=\"wp-block-heading\">How can I check my custom connection configuration?<\/h3>\n\n<p class=\"wp-block-paragraph\">Worried you made a mistake? You can check that your configuration was correct with the code below:<\/p>\n    <div data-content-type=\"longform\" class=\"code-snippet longform-spacings rounded-lg overflow-hidden shadow \" data-count=\"1\">\r\n        <ul class=\"nav nav-buttons code-snippet__tabs longform-except position-relative d-flex gap-2 flex-wrap p-3\" role=\"tablist\">\r\n\r\n                            \r\n                    \r\n                        <li class=\"nav-item\" role=\"presentation\">\r\n                            <button class=\"nav-link active\" data-bs-toggle=\"tab\" data-bs-target=\"#code_0\" type=\"button\" role=\"tab\" aria-controls=\"code_0\" aria-selected=\"true\">\r\n                                Shell                            <\/button>\r\n                        <\/li>\r\n\r\n                    \r\n                            \r\n        <\/ul>\r\n        <div class=\"code-snippet__tab-content tab-content\">\r\n\r\n                            \r\n                    <div class=\"tab-pane show active\" id=\"code_0\" role=\"tabpanel\" aria-labelledby=\"code_0\">\r\n                        <div class=\"code-snippet__code-wrapper\">\r\n                            <div class=\"nav nav-buttons code-snippet__copy-wrapper\">\r\n                                <button type=\"button\" class=\"nav-link code-snippet__copy\" data-clipboard-target=\"#code_0_content\" data-clipboard-label=\"Copier dans le presse-papiers\" data-clipboard-success-label=\"Copi\u00e9\u00a0!\" data-clipboard-error-label=\"Impossible de copier\" data-tooltip=\"Copier dans le presse-papiers\" data-tooltip-placement=\"left\" role=\"tooltip\" aria-label=\"Copier dans le presse-papiers\">\r\n                                    <svg class=\"code-snippet__copy-icon code-snippet__copy-icon--default\" width=\"24\" height=\"24\" aria-hidden=\"true\" data-url=\"https:\/\/www.mailgun.com\/wp-content\/plugins\/sinch-core\/assets\/icons\/sinch\/file-stack.svg\"><\/svg>\r\n                                    <svg class=\"code-snippet__copy-icon code-snippet__copy-icon--success\" width=\"24\" height=\"24\" aria-hidden=\"true\" data-url=\"https:\/\/www.mailgun.com\/wp-content\/plugins\/sinch-core\/assets\/icons\/sinch\/badge-check.svg\"><\/svg>\r\n                                <\/button>\r\n                            <\/div>\r\n                            <pre class=\"w-100 h-100 m-0 line-numbers language-shell\">\r\n                                <code id=\"code_0_content\" class=\"language-shell\">\r\n\r\n                                    curl -sk --user &#039;api:API_KEY&#039;   \r\n    -X GET https:\/\/api.mailgun.net\/v3\/domains\/DOMAIN_NAME\/connection\r\n                                <\/code>\r\n                            <\/pre>\r\n                        <\/div>\r\n                    <\/div>\r\n                                    <\/div>\r\n    <\/div>\r\n\n<h2 class=\"wp-block-heading\">Wrapping up<\/h2>\n\n<p class=\"wp-block-paragraph\">And that\u2019s it! We\u2019ve learned how the TLS protocol works and some ways you can customize your connection settings with Mailgun.<\/p>\n\n<p class=\"wp-block-paragraph\">If you\u2019re interested in learning more, check out our documentation <a href=\"https:\/\/documentation.mailgun.com\/en\/latest\/user_manual.html\" target=\"_tabs\" rel=\"noopener noreferrer\">here<\/a>, or sign up for a <a href=\"https:\/\/www.mailgun.com\/fr\/\" target=\"_tabs\" rel=\"noopener noreferrer\">free trial<\/a>.<\/p>\n\r\n    <aside data-content-type=\"longform\"  class=\"banner-block longform-spacings rounded-lg shadow-lg px-5 py-6 px-md-6 py-md-7 p-lg-7 bg-light\" data-theme=\"dark\" aria-labelledby=\"banner-block-block_c98f95c79477624b12c784aef115ef28\">\r\n                    <p class=\"text-uppercase section-caption text-body-color\">\r\n                Sign Up            <\/p>\r\n                            <p class=\"h4 text-accent fw-bold\" id=\"banner-block-block_c98f95c79477624b12c784aef115ef28\">\r\n                It&rsquo;s easy to get started. And it&rsquo;s free.            <\/p>\r\n                            <div class=\"mb-0 text-body-color\">\r\n                                    <div class=\"content-body mb-0 text-body-color\">See what you can accomplish with the world\u2019s best email delivery platform.<\/div>\r\n                            <\/div>\r\n        \r\n        <div class=\"text-start mt-5\"><a href=\"https:\/\/signup.mailgun.com\/new\/signup\"  class=\"btn btn-secondary\" >Get started<\/a><\/div>\r\n    <\/aside>\r\n\r\n","protected":false},"excerpt":{"rendered":"<p>Dans cet article, nous vous montrerons comment utiliser le TLS pour chiffrer vos communications par email en toute s\u00e9curit\u00e9.<\/p>\n","protected":false},"author":13,"featured_media":4555,"menu_order":0,"template":"","meta":{"_acf_changed":false,"footnotes":""},"blog_category":[22],"class_list":["post-23731","blog","type-blog","status-publish","has-post-thumbnail","hentry","blog_category-product"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.4 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Les bases du TLS\u00a0: qu&#039;est-ce que le contr\u00f4le de connexion TLS\u00a0? - Transactional Email API Service For Developers | Mailgun<\/title>\n<meta name=\"description\" content=\"Vous voulez savoir comment prot\u00e9ger vos emailsu00A0? 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