ISO/IEC 9797-2:2021 - Information security — Message authentication codes (MACs) — Part 2: Mechanisms using a dedicated hash-function

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International Organization for Standardization"> </div> <nav role="navigation" aria-label="Children Navigation" class="heading-condensed nav-relatives"> <div class="section-head "></div> <h1 class="stdTitle"> <span class="d-flex justify-content-between align-items-start"> <span class="d-block mb-3 ">ISO/IEC 9797-2:2021</span> </span> <span class="lead d-block mb-3">Information security — Message authentication codes (MACs)</span><span class="lead d-block fw-semibold">Part 2: Mechanisms using a dedicated hash-function</span></h1> </nav> <div class="mt-4 callout callout-success callout-top"> <div class="mb-1"><a href="#lifecycle" class="text-success" title="Life cycle"><strong>Published</strong></a> (Edition 3, 2021)</div> </div> </div> </div> </div> <div class="col-md-4 col-md-offset-1"> <div class="card store-box buy-box buybox" id="cs75296"> <div class="card-header text-center"><h4>ISO/IEC 9797-2:2021</h4></div> <div class="card-body"> <span class="visually-hidden" id="indexReference_cs75296" data-index="75296 - ISO/IEC 9797-2:2021 - Information security — Message authentication codes (MACs) — Part 2: Mechanisms using a dedicated hash-function"></span> <span class="visually-hidden" id="itemReference_cs75296">ISO/IEC 9797-2:2021</span> <div class="visually-hidden" id="csNumber_cs75296">75296</div> <form class="box-option" id="form_cs75296"> <div class="mb-3"> <div class="section-head mb-1 text-sm"> Language</div> <div class="form-group"> <select class="form-select form-select-sm bkilang" id="bkilang_cs75296"> <option value="en" selected>English</option> </select> </div> </div> <div class="section-head mb-1 text-sm"> Format</div> <div class="formats formats_cs75296" id="bkifmt_cs75296_en" style="display: none;"><div class="form-check text-sm" id="bkifmt_cs75296_en_1"> <input class="form-check-input" data-type="std" data-price="194" checked="checked" type="radio" name="format_en" id="format_cs75296_en_1" value="01ub000000289qgAAA~a05b0000005WV3eAAG~a0f6700000fYqYnAAK~a0c6700000TNw0SAAT"/> <label class="form-check-label" for="format_cs75296_en_1">PDF + ePub</label> </div><div class="form-check text-sm" id="bkifmt_cs75296_en_2"> <input class="form-check-input" data-type="std" data-price="194" type="radio" name="format_en" id="format_cs75296_en_2" value="01ub000000289qgAAA~a05b0000005WV3jAAG~a0fb0000000ePbKAAU~a0c6700000TNvuzAAD"/> <label class="form-check-label" for="format_cs75296_en_2">Paper</label> </div></div></form> <div class="align-items-baseline box-price" itemprop="offers" itemscope itemtype="https://schema.org/Offer"> <div class="d-flex justify-content-center align-items-baseline gap-2"> <link itemprop="url" href="https://www.iso.org:-1/standard/75296.html" /> <meta itemprop="availability" content="https://schema.org/InStock" /> <span class="currency"><abbr title="Swiss francs" itemprop="priceCurrency">CHF</abbr></span> <span class="price d-flex align-items-baseline gap-2"> <span class="amount" id="productPrice_cs75296" itemprop="price">194</span> </span> </div> </div> <div class="d-grid orderBasket box-action pb-0"> <button id="add_cs75296" class="btn btn-primary" data-bs-toggle="modal" data-bs-target="#iso-optout" onclick="javascript:addToBasket('cs75296', '1', 'en', 'cs')"> Add to cart</button> </div> </div> <div id="priceConverter" class="smaller text-center p-3">Convert Swiss francs (CHF) to <a id="convertLink_cs75296" target="_blank" href="https://www.xe.com/en/currencyconverter/convert/?Amount=194&From=CHF&To=EUR">your currency</a></div> </div> </div> </div> </div> </section> <svg class="wave" preserveAspectRatio="none" viewBox="0 0 1440 96" fill="none" xmlns="http://www.w3.org/2000/svg"><path d="m0 96 80-5.3C160 85 320 75 480 64s320-21 480-21.3c160 .3 320 10.3 400 16l80 5.3V0H0v96Z"></path></svg> <section id="product-details"> <div class="container"> <div class="row"> <div class="col-md-7"> <div class="d-flex justify-content-between align-items-center"><h2>Abstract</h2></div> <div itemprop="description"> <p><p>This document specifies MAC algorithms that use a secret key and a hash-function (or its round-function or sponge function) to calculate an <em>m</em>-bit MAC. These mechanisms can be used as data integrity mechanisms to verify that data has not been altered in an unauthorized manner.</p> <p>NOTE A general framework for the provision of integrity services is specified in ISO/IEC 10181‑6.</p></p> </div> </div> <div class="col-md-4 col-md-offset-1"> <div class="d-flex justify-content-between align-items-center"> <h3>General information</h3> </div> <ul class="refine"> <li> <div class="" id="publicationStatus"> <div class="entry-label">Status</div> : <span>Published</span> </div> <div class="" id="publicationDate"> <div class="entry-label">Publication date</div> : <span itemprop="releaseDate">2021-06</span> </div> <div class="" id="stageId"> <div class="entry-label">Stage</div> : International Standard published [<a class="page-scroll" href="#lifecycle">60.60</a>] </div> </li> <li> <div class=""> <div class="entry-label">Edition</div> : 3</div> <div class=""> <div class="entry-label">Number of pages</div> : 52</div> </li> <li> <div> <div class="entry-label">Technical Committee :</div> <span class="entry-name entry-block"> <a title="Information security, cybersecurity and privacy protection" href="/committee/45306.html">ISO/IEC JTC 1/SC 27</a></span> </div> <div> <div class="entry-label"><abbr class="popover-primary" tabindex="0" role="button" data-bs-toggle="popover" data-bs-custom-class="popover-light text-sm shadow-sm pt-2" data-bs-trigger="focus" data-bs-placement="bottom" data-bs-content="International Classification for Standards">ICS</abbr> :</div> <span class="entry-name entry-block"> <a title="IT Security" href="/ics/35.030.html"> 35.030</a>  </span> </div> </li> <li class="text-xs"> <i class="bi-rss-fill me-1 align-baseline text-sm" style="color: #F99000;"></i><a href="/contents/data/standard/07/52/75296.detail.rss">RSS</a> updates</li> </ul> </div> </div> </div> </section> </div> <section id="lifecycle" class="z-2"> <div class="container"> <div class="row"> <div class="col-md-12"> <h3>Life cycle</h3> <div class="lifecycle"> <ul class="steps"> <li class="time-step"> <h4 class="ms-sm-3 text-muted">Previously</h4> <div class="step step-dark"> <div class="step-item"> <div class="section-head">Withdrawn</div> <h5><a href="/standard/51618.html">ISO/IEC 9797-2:2011</a></h5> </div> </div> </li> <li class="time-step"> <h4 class="ms-sm-3 text-muted">Now</h4> <div class="step step-success active"> <div class="section-head">Published</div> <h5>ISO/IEC 9797-2:2021</h5> <a data-bs-toggle="collapse" role="button" aria-expanded="false" href="#stages" class="dropdown-toggle current-stage text-sm collapsed">Stage: <strong>60.60</strong></a> </div> <ul class="stages collapse" id="stages"> <li class="dropdown alert-info"> <a href="javascript:void(0)" role="button" aria-haspopup="true" aria-expanded="false"> <span class="stage-code">00</span> <div class="stage-title">Preliminary</div> </a> </li> <li class="dropdown alert-info"> <a href="javascript:void(0)" class="dropdown-toggle" data-bs-display="static" data-bs-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false"> <span class="stage-code">10</span> <div class="stage-title">Proposal</div> </a> <ul class="dropdown-menu"> <li > <a href="/stage-codes.html#10_99"> <span class="stage-code">10.99</span> <span class="stage-date">2018-01-11</span> <div class="stage-title"> New project approved</div> </a> </li></ul> </li> <li class="dropdown alert-info"> <a href="javascript:void(0)" class="dropdown-toggle" data-bs-display="static" data-bs-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false"> <span class="stage-code">20</span> <div class="stage-title">Preparatory</div> </a> <ul class="dropdown-menu"> <li > <a href="/stage-codes.html#20_00"> <span class="stage-code">20.00</span> <span class="stage-date">2018-01-11</span> <div class="stage-title"> New project registered in TC/SC work programme</div> </a> </li><li > <a href="/stage-codes.html#20_20"> <span class="stage-code">20.20</span> <span class="stage-date">2018-09-03</span> <div class="stage-title"> Working draft (WD) study initiated</div> </a> </li><li > <a href="/stage-codes.html#20_60"> <span class="stage-code">20.60</span> <span class="stage-date">2018-10-04</span> <div class="stage-title"> Close of comment period</div> </a> </li><li > <a href="/stage-codes.html#20_20"> <span class="stage-code">20.20</span> <span class="stage-date">2018-12-06</span> <div class="stage-title"> Working draft (WD) study initiated</div> </a> </li><li > <a href="/stage-codes.html#20_60"> <span class="stage-code">20.60</span> <span class="stage-date">2019-02-28</span> <div class="stage-title"> Close of comment period</div> </a> </li></ul> </li> <li class="dropdown alert-info"> <a href="javascript:void(0)" class="dropdown-toggle" data-bs-display="static" data-bs-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false"> <span class="stage-code">30</span> <div class="stage-title">Committee</div> </a> <ul class="dropdown-menu"> <li > <a href="/stage-codes.html#30_00"> <span class="stage-code">30.00</span> <span class="stage-date">2019-07-04</span> <div class="stage-title"> Committee draft (CD) registered</div> </a> </li><li > <a href="/stage-codes.html#30_20"> <span class="stage-code">30.20</span> <span class="stage-date">2019-07-04</span> <div class="stage-title"> CD consultation initiated</div> </a> </li><li > <a href="/stage-codes.html#30_60"> <span class="stage-code">30.60</span> <span class="stage-date">2019-08-30</span> <div class="stage-title"> Close of comment period</div> </a> </li><li > <a href="/stage-codes.html#30_99"> <span class="stage-code">30.99</span> <span class="stage-date">2020-06-23</span> <div class="stage-title"> CD approved for registration as DIS</div> </a> </li></ul> </li> <li class="dropdown alert-info"> <a href="javascript:void(0)" class="dropdown-toggle" data-bs-display="static" data-bs-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false"> <span class="stage-code">40</span> <div class="stage-title">Enquiry</div> </a> <ul class="dropdown-menu"> <li > <a href="/stage-codes.html#40_00"> <span class="stage-code">40.00</span> <span class="stage-date">2020-06-30</span> <div class="stage-title"> DIS registered</div> </a> </li><li > <a href="/stage-codes.html#40_20"> <span class="stage-code">40.20</span> <span class="stage-date">2020-09-01</span> <div class="stage-title"> DIS ballot initiated: 12 weeks</div> </a> </li><li > <a href="/stage-codes.html#40_60"> <span class="stage-code">40.60</span> <span class="stage-date">2020-11-25</span> <div class="stage-title"> Close of voting</div> </a> </li><li > <a href="/stage-codes.html#40_99"> <span class="stage-code">40.99</span> <span class="stage-date">2021-03-16</span> <div class="stage-title"> Full report circulated: DIS approved for registration as FDIS</div> </a> </li></ul> </li> <li class="dropdown alert-info"> <a href="javascript:void(0)" class="dropdown-toggle" data-bs-display="static" data-bs-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false"> <span class="stage-code">50</span> <div class="stage-title">Approval</div> </a> <ul class="dropdown-menu"> <li > <a href="/stage-codes.html#50_00"> <span class="stage-code">50.00</span> <span class="stage-date">2021-03-17</span> <div class="stage-title"> Final text received or FDIS registered for formal approval</div> </a> </li><li > <a href="/stage-codes.html#50_20"> <span class="stage-code">50.20</span> <span class="stage-date">2021-04-28</span> <div class="stage-title"> Proof sent to secretariat or FDIS ballot initiated: 8 weeks</div> </a> </li><li > <a href="/stage-codes.html#50_60"> <span class="stage-code">50.60</span> <span class="stage-date">2021-05-26</span> <div class="stage-title"> Close of voting. Proof returned by secretariat</div> </a> </li></ul> </li> <li class="dropdown bg-success active"> <a href="javascript:void(0)" class="dropdown-toggle" data-bs-display="static" data-bs-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false"> <span class="stage-code">60</span> <div class="stage-title">Publication</div> </a> <ul class="dropdown-menu"> <li > <a href="/stage-codes.html#60_00"> <span class="stage-code">60.00</span> <span class="stage-date">2021-05-26</span> <div class="stage-title"> International Standard under publication</div> </a> </li><li class="active"> <a href="/stage-codes.html#60_60"> <span class="stage-code">60.60</span> <span class="stage-date">2021-06-23</span> <div class="stage-title"> International Standard published</div> </a> </li></ul> </li> <li class="dropdown alert-muted"> <a href="javascript:void(0)" class="dropdown-toggle" data-bs-display="static" data-bs-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false"> <span class="stage-code">90</span> <div class="stage-title">Review</div> </a> <ul class="dropdown-menu"> <li class='list-separation'> <a href="/stage-codes.html#90_20"> <span class="stage-code">90.20</span> <span class="stage-date"></span> <div class="stage-title"> International Standard under systematic review</div> </a> </li><li > <a href="/stage-codes.html#90_60"> <span class="stage-code">90.60</span> <span class="stage-date"></span> <div class="stage-title"> Close of review</div> </a> </li><li > <a href="/stage-codes.html#90_92"> <span class="stage-code">90.92</span> <span class="stage-date"></span> <div class="stage-title"> International Standard to be revised</div> </a> </li><li > <a href="/stage-codes.html#90_93"> <span class="stage-code">90.93</span> <span class="stage-date"></span> <div class="stage-title"> International Standard confirmed</div> </a> </li><li > <a href="/stage-codes.html#90_99"> <span class="stage-code">90.99</span> <span class="stage-date"></span> <div class="stage-title"> Withdrawal of International Standard proposed by TC or SC</div> </a> </li></ul> </li> <li class="dropdown alert-muted"> <a href="javascript:void(0)" class="dropdown-toggle" data-bs-display="static" data-bs-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false"> <span class="stage-code">95</span> <div class="stage-title">Withdrawal</div> </a> <ul class="dropdown-menu"> <li > <a href="/stage-codes.html#95_99"> <span class="stage-code">95.99</span> <span class="stage-date"></span> <div class="stage-title"> Withdrawal of International Standard</div> </a> </li></ul> </li> </ul> <div class="sub-step sub-step-cor"> <div class="step step-info"> <h5>Corrigenda</h5> <div class="text-sm mb-2" style="max-width: 400px;">Correct the current edition; 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remove_tooltip(elem) : false; if (elem.type != 'checkbox') elem.className = elem.className.replace(/ ?_has_error ?/g, ''); if (elem.getAttribute('required') !== null) { if (elem.type == 'radio' || (elem.type == 'checkbox' && /any/.test(elem.className))) { var elems = form_to_submit.elements[elem.name]; if (!(elems instanceof NodeList || elems instanceof HTMLCollection) || elems.length <= 1) { no_error = elem.checked; } else { no_error = false; for (var i = 0; i < elems.length; i++) { if (elems[i].checked) no_error = true; } } if (!no_error) { tooltip = create_tooltip(elem, "Please select an option."); } } else if (elem.type =='checkbox') { var elems = form_to_submit.elements[elem.name], found = false, err = []; no_error = true; for (var i = 0; i < elems.length; i++) { if (elems[i].getAttribute('required') === null) continue; if (!found && elems[i] !== elem) return true; found = true; elems[i].className = elems[i].className.replace(/ ?_has_error ?/g, ''); if (!elems[i].checked) { no_error = false; elems[i].className = elems[i].className + ' _has_error'; err.push("Checking %s is required".replace("%s", elems[i].value)); } } if (!no_error) { tooltip = create_tooltip(elem, err.join('<br/>')); } } else if (elem.tagName == 'SELECT') { var selected = true; if (elem.multiple) { selected = false; for (var i = 0; i < elem.options.length; i++) { if (elem.options[i].selected) { selected = true; break; } } } else { for (var i = 0; i < elem.options.length; i++) { if (elem.options[i].selected && (!elem.options[i].value || (elem.options[i].value.match(/\n/g)))) { selected = false; } } } if (!selected) { elem.className = elem.className + ' _has_error'; no_error = false; tooltip = create_tooltip(elem, "Please select an option."); } } else if (value === undefined || value === null || value === '') { elem.className = elem.className + ' _has_error'; no_error = false; tooltip = create_tooltip(elem, "This field is required"); } } if (no_error && (elem.id == 'field[]' || elem.id == 'ca[11][v]')) { if (elem.className.includes('phone-input-error')) { elem.className = elem.className + ' _has_error'; no_error = false; } } if (no_error && elem.name == 'email') { if (!value.match(/^[\+_a-z0-9-'&=]+(\.[\+_a-z0-9-']+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,})$/i)) { elem.className = elem.className + ' _has_error'; no_error = false; tooltip = create_tooltip(elem, 'Please enter a valid email address'); } } if (no_error && /date_field/.test(elem.className)) { if (!value.match(/^\d\d\d\d-\d\d-\d\d$/)) { elem.className = elem.className + ' _has_error'; no_error = false; tooltip = create_tooltip(elem, "Enter a valid date."); } } tooltip ? resize_tooltip(tooltip) : false; return no_error; }; var needs_validate = function(el) { if(el.getAttribute('required') !== null){ return true } if(el.name === 'email' && el.value !== ""){ return true } if((el.id == 'field[]' || el.id == 'ca[11][v]') && el.className.includes('phone-input-error')){ return true } return false }; var validate_form = function(e) { var err = form_to_submit.querySelector('._form_error'), no_error = true; if (!submitted) { submitted = true; for (var i = 0, len = allInputs.length; i < len; i++) { var input = allInputs[i]; if (needs_validate(input)) { if (input.type == 'tel') { addEvent(input, 'blur', function() { this.value = this.value.trim(); validate_field(this, true); }); } if (input.type == 'text' || input.type == 'number' || input.type == 'time') { addEvent(input, 'blur', function() { this.value = this.value.trim(); validate_field(this, true); }); addEvent(input, 'input', function() { validate_field(this, true); }); } else if (input.type == 'radio' || input.type == 'checkbox') { (function(el) { var radios = form_to_submit.elements[el.name]; for (var i = 0; i < radios.length; i++) { addEvent(radios[i], 'click', function() { validate_field(el, true); }); } })(input); } else if (input.tagName == 'SELECT') { addEvent(input, 'change', function() { validate_field(this, true); }); } else if (input.type == 'textarea'){ addEvent(input, 'input', function() { validate_field(this, true); }); } } } } remove_tooltips(); for (var i = 0, len = allInputs.length; i < len; i++) { var elem = allInputs[i]; if (needs_validate(elem)) { if (elem.tagName.toLowerCase() !== "select") { elem.value = elem.value.trim(); } validate_field(elem) ? true : no_error = false; } } if (!no_error && e) { e.preventDefault(); } resize_tooltips(); return no_error; }; addEvent(window, 'resize', resize_tooltips); addEvent(window, 'scroll', resize_tooltips); var hidePhoneInputError = function(inputId) { var errorMessage = document.getElementById("error-msg-" + inputId); var input = document.getElementById(inputId); errorMessage.classList.remove("phone-error"); errorMessage.classList.add("phone-error-hidden"); input.classList.remove("phone-input-error"); }; var initializePhoneInput = function(input, defaultCountry) { return window.intlTelInput(input, { utilsScript: "https://unpkg.com/intl-tel-input@17.0.18/build/js/utils.js", autoHideDialCode: false, separateDialCode: true, initialCountry: defaultCountry, preferredCountries: [] }); } var setPhoneInputEventListeners = function(inputId, input, iti) { input.addEventListener('blur', function() { var errorMessage = document.getElementById("error-msg-" + inputId); if (input.value.trim()) { if (iti.isValidNumber()) { iti.setNumber(iti.getNumber()); if (errorMessage.classList.contains("phone-error")){ hidePhoneInputError(inputId); } } else { showPhoneInputError(inputId) } } else { if (errorMessage.classList.contains("phone-error")){ hidePhoneInputError(inputId); } } }); input.addEventListener("countrychange", function() { iti.setNumber(''); }); input.addEventListener("keydown", function(e) { var charCode = (e.which) ? e.which : e.keyCode; if (charCode > 31 && (charCode < 48 || charCode > 57) && charCode !== 8) { e.preventDefault(); } }); }; var showPhoneInputError = function(inputId) { var errorMessage = document.getElementById("error-msg-" + inputId); var input = document.getElementById(inputId); errorMessage.classList.add("phone-error"); errorMessage.classList.remove("phone-error-hidden"); input.classList.add("phone-input-error"); }; var form_submit = function(e) { e.preventDefault(); if (validate_form()) { // use this trick to get the submit button & disable it using plain javascript document.querySelector('#_form_23_submit').disabled = true; var _form_serialize_23 = function(form){if(!form||form.nodeName!=="FORM"){return }var i,j,q=[];for(i=0;i<form.elements.length;i++){if(form.elements[i].name===""){continue}switch(form.elements[i].nodeName){case"INPUT":switch(form.elements[i].type){case"tel":q.push(form.elements[i].name+"="+encodeURIComponent(form.elements[i].previousSibling.querySelector('div.iti__selected-dial-code').innerText)+encodeURIComponent(" ")+encodeURIComponent(form.elements[i].value));break;case"text":case"number":case"date":case"time":case"hidden":case"password":case"button":case"reset":case"submit":q.push(form.elements[i].name+"="+encodeURIComponent(form.elements[i].value));break;case"checkbox":case"radio":if(form.elements[i].checked){q.push(form.elements[i].name+"="+encodeURIComponent(form.elements[i].value))}break;case"file":break}break;case"TEXTAREA":q.push(form.elements[i].name+"="+encodeURIComponent(form.elements[i].value));break;case"SELECT":switch(form.elements[i].type){case"select-one":q.push(form.elements[i].name+"="+encodeURIComponent(form.elements[i].value));break;case"select-multiple":for(j=0;j<form.elements[i].options.length;j++){if(form.elements[i].options[j].selected){q.push(form.elements[i].name+"="+encodeURIComponent(form.elements[i].options[j].value))}}break}break;case"BUTTON":switch(form.elements[i].type){case"reset":case"submit":case"button":q.push(form.elements[i].name+"="+encodeURIComponent(form.elements[i].value));break}break}}return q.join("&")}; let serialized_23 = _form_serialize_23(document.getElementById('_form_23_')).replace(/%0A/g, '\\n'); var err = form_to_submit.querySelector('._form_error'); err ? err.parentNode.removeChild(err) : false; // We don't check the Google reCaptcha if projectId is null // Site properties: ProjectId is defined => we check the captcha before sending the form _check_reCaptcha_23(); } return false; }; addEvent(form_to_submit, 'submit', form_submit); })(); </script> <details class="text-xs"><summary style="color:inherit">How your data will be used</summary> <p class="pt-2">Please see <a href="/privacy.html" title="privacy-and-copyright">ISO privacy notice</a>. This site is protected by reCAPTCHA and the Google <a href="https://policies.google.com/privacy">Privacy Policy</a> and <a href="https://policies.google.com/terms">Terms of Service</a> apply.</p> </details></div></div></div> <div class="footer-social clearfix"> <ul itemscope itemtype="https://schema.org/Organization"> <link itemprop="url" href="https://www.iso.org/"> <li><a itemprop="sameAs" target="_blank" rel="noopener" href="https://www.linkedin.com/company/isostandards" title="Linkedin"><i class="bi-linkedin"></i></a></li> <li><a itemprop="sameAs" target="_blank" rel="noopener" href="https://twitter.com/isostandards" title="Twitter"><i class="bi-twitter"></i></a></li> <li><a itemprop="sameAs" target="_blank" rel="noopener" href="https://www.facebook.com/isostandards" title="Facebook"><i class="bi-facebook"></i></a></li> <li><a itemprop="sameAs" target="_blank" rel="noopener" href="https://www.instagram.com/isostandards" title="Instagram"><i class="bi-instagram"></i></a></li> <li><a itemprop="sameAs" target="_blank" rel="noopener" href="https://www.youtube.com/ISO" title="YouTube"><i class="bi-youtube"></i></a></li> <li><a itemprop="sameAs" target="_blank" rel="noopener" href="https://www.flickr.com/photos/isostandards" title="Flickr"><i class="bi-flickr"></i></a></li> </ul> </div> <p class="display-5 opacity-100">Making lives <strong><em>easier</em></strong>, <strong><em>safer</em></strong> and <strong><em>better</em></strong>.</p> <div class="row"> <div class="col-md-8 col-md-offset-2 pull-left"> <p class="text-xs">We are committed to ensuring that our website is accessible to everyone. 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ISO/IEC 9797-2:2021 - Information security — Message authentication codes (MACs) — Part 2: Mechanisms using a dedicated hash-function