CINXE.COM

<!DOCTYPE html><html lang="en-US"><head><title>Just a moment...</title><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=Edge"><meta name="robots" content="noindex,nofollow"><meta name="viewport" content="width=device-width,initial-scale=1"><style>*{box-sizing:border-box;margin:0;padding:0}html{line-height:1.15;-webkit-text-size-adjust:100%;color:#313131;font-family:system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,Noto Sans,sans-serif,Apple Color Emoji,Segoe UI Emoji,Segoe UI Symbol,Noto Color Emoji}body{display:flex;flex-direction:column;height:100vh;min-height:100vh}.main-content{margin:8rem auto;max-width:60rem;padding-left:1.5rem}@media (width <= 720px){.main-content{margin-top:4rem}}.h2{font-size:1.5rem;font-weight:500;line-height:2.25rem}@media (width <= 720px){.h2{font-size:1.25rem;line-height:1.5rem}}#challenge-error-text{background-image:url(data:image/svg+xml;base64,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);background-repeat:no-repeat;background-size:contain;padding-left:34px}@media (prefers-color-scheme:dark){body{background-color:#222;color:#d9d9d9}}</style><meta http-equiv="refresh" content="390"></head><body class="no-js"><div class="main-wrapper" role="main"><div class="main-content"><noscript><div class="h2"><span id="challenge-error-text">Enable JavaScript and cookies to continue</span></div></noscript></div></div><script>(function(){window._cf_chl_opt={cvId: '3',cZone: "tools.ietf.org",cType: 'managed',cRay: '92b1dab1283948ee',cH: 'NVunwojgwfVMOv5uatUmAupHug7k4gaaNj3IJr.TCog-1743780702-1.2.1.1-77dyGN2kDFfPkk0WrETrgFERFYwiYuqCJAF9j5EHH5oyaPH0sZRM_sudQ2z7jDX4',cUPMDTk: "\/doc\/rfc3236\/?__cf_chl_tk=AZsOsZuh.YoKqvl_lyG0NSahsGh1ogHTtErR9ylGyYs-1743780702-1.0.1.1-79cCJL5B0JyUG5b4wVavt5RR7cShmzuSDANDfGIpz1U",cFPWv: 'g',cITimeS: '1743780702',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/doc\/rfc3236\/?__cf_chl_f_tk=AZsOsZuh.YoKqvl_lyG0NSahsGh1ogHTtErR9ylGyYs-1743780702-1.0.1.1-79cCJL5B0JyUG5b4wVavt5RR7cShmzuSDANDfGIpz1U",md: "A4ZeotakG_FSfwkjHNmKtWCzS0LSPX3K4hw83NIJ9M0-1743780702-1.2.1.1-0sc7sMRUSlV71VHImMlEhOgeY.doqRr5se..9KzFbu.VhwM.pVIrJ62YuBnvd2j_W9MIBy_erkWN7anIcGSy7LrLAfDlubRBZfBN0HZZ4a_T5GTUVvOwZ3VZIgFEbyBlTaVJ0YiLQ.OZrGUbyRRNeZ_BvWAgMHgqmS._N5Vv9eBmzFvtC_0YTOHNUTReSfNdV4FbmTIphWJYV572PPjHuQqAHtJphr3l7Twlp0zwbAHj1AtOpbTHLOO4WBNi65z4RvZv7KwbXg_zdQcLUR9vCgzCWauQ.GFw7kqHoAb47AfDXHw7QZZ8eydZtnJckRQY1p2hBrBjA6xvS3Yyt6l9Ckxtt64vKuChfwgoLtHG0GYVWvRxgypcRpxINQqG7mAf75SyL40nfDJQVJ9._KZX.kq44lAxGwsAiRD2FFdaDq4iKmHElGl47tse0pSpU7I_vZ3cTD5ZQur8k.XgKFm_jrsxHg2BxFZ1J3FTTI0Asec_2w_KJhq7UxZ.Hen53DW.78pJL77P08lJ3BBDkpLEkBtom0HzPgCdOjfrSWpLzZRUmPUopyB4XS_du5FSmJYAxQbCnWh4euCLX8oHBO9v06S4iZHMNJV0VycWFSoCER9P8bxqLQAq15PxTomtSSDOPiJqhhKwmdlCziXKu.M2mARDvrFxCDvwVJ.z4djP0SsvhHTrjYwEnpWu3OfA8vS3Lpgv5U1EgJsi1qWmm9SYsocLQEeOIPngw2R1mmU29c3L9qNnOrPhb3I44IeojrZyVaS4uatUPv3XzwRNljzBbGIkLKM2E3PACnltfqSnAgByTqL7hehEnwpLHJFt1Al3olmcV9pgKRfD5kOg9hPp3cvcV6oLYu2ds_cK9yUqYuZSyw5TbDz8gHQuDO8Q2lJaX6NwmSwec3o.I62SwhIuopp1nldB9Jg_J44_gczqmeP0BnxApB65bxt.VZoWTqhpLgb0B2l7R3biXMOdOhqzImepk4hSi3fE6Sb5QvPoVJNgot7vNaZd2ZBAnDU8A87o7fFmr2mbRaX2XTmPDBkZwOua1MjyyhNn0WWRj8_aK_JQ6DlgAGZZ1Ue_u6z2C7kPV5F3yg8umYZDIrooL.GRAYifzc3_auxdyrqjwdm3NM.luO_fcXwVr_jmBv3k1oweJv0D3HOlqCqj5mMDnib7kGNoJPiC6I2zLSP.X96tGls2cuFOUef70DKf6J8sXT0tXWbwThFfpsf8yUN8HXFieuB5qd1ja6fXFwFCfXqoTkQ",mdrd: "htka8JcWwIoDiGM4plmvtXqrYaumOi6kADcg4h5GZEc-1743780702-1.2.1.1-OTWashtOvJoG_dDiGA98H3Nws7WeYDDffw4pnrSQ71Vepu0EBKW8rzx_a2qBFeaKTZY7vDPEIN_w7FqCGS0wBtyIdl5z4kQE19yOHEFo.cDdwFzMS_xyRe4CGiQn8ohEnW2cZRSllGHuUIuKCssU0IqcwZTRGV1u_aPbnxRDQia4MKlkk72M8zZHzlsVXjmKGM1yYHx_LXdzWQmPyEZbp5eebDLtWfwrcnYpwL0goIncWqp4MbBfcYEtg.tEow2iF_N9MLf1mIgBfF998gwW.OjMbl8KnJXeMvfja97OrigllojvvGXBr4JSxDPXDcFF.0ITqcrj0PFyOdAoBBKGs8awasFSoGBhCjUH8aKZnVORFhk5j6.JrGGoeICsfTx3PMIDa7N6D.JSr59l7UTO80LBCRlF23CBpspcmHGkSKI0BpyEWlzLLimd_0UsUVw6l6wVJLgrw2qm7h5bTXd.TAIU8kFssaJnGH2TWgWUmCCwr.5UQ8cihh9X25T4c_CSdtwhFoW_EYfbYnPAs.9bND9XH3O.L.EXPYubjZsPImlCl_Iick6s6q6s085ypeU7gcqhRrUhMSVDWHWBDhxlOWasqihFpsMuYLvjYVeg4fLa4P.wfGH3581vSfxK.i6EE8JHsLdYeGQ6QLP0uGGhZzXWMiwjih6W8Edci421hiOXVSObBJTtjQv0OHDQSV7TtDQzupa_CNUSpnsfynRmbQPSuFf5oOwd80cXMOqF_n7e0AM42m26YVoLYvc03lxLkKB0f6MtptxCas6zMgWTG9jVkvjYKULTzWIvF78pRduhPPrqx_N88pGLZIG9DemYCRnZoAuBKc5oVrMaaYEWKlina1aznHslsjqiLdTpYw5uzhO8_7gyCzr8e44Wui_it6M17XQ8owV7jbq5M7xKxcw6u.tdcNnN0V5aBt8t_KOMYKPp99YDzhLYPj8s0cUkz9u9yfLfgG6aYxJTu4JbhQO9Qxu5iiTf1w2SPazpEiv70bYR9mw4fvewGPoXyzNy4I5IolA57DkXx_4.UKbg7cC2bKitmXOPpEsQuJkH.Yvwt0biRAQ_d.B1PY7T8LlSElhCFKcS_UVlTc._Ep6YSsuJfG5RTIYt5fHiK1i37QtSUM1yhTm7Jf8Uf1N4nxV7A_LxKUfu0IS91wSKJL5Ezcym6X072IM3.NlMkaAiBYbijelEhfZSh3VMc2CprgjJ7_iuupuJPxEYCYlk.yAwN9dZusGJNJCWP6Sh2vMTCib4IqqUZZvPx2.Pj2LSYDbE7VmB7qkqKEAk2I4omACVmNXpClqwm993b3k4SbsflcjfOEbs5zg7YAZK2SQZj6_vhOMdOS27RQmkvUJYuyHmx1zDVtOs_KTggN_O6n0wJy0TOEm6e8SqzvRPInxh9LgEiTxtP9esoIMlMah92BO5lC_V3NJ6isX9Y6hPRqpyz4hJ_6krxoaOqMlGuv79QBFLGBr7ai8JF_pjalmfK73TU9h_5SR5PrpMG3KyKaSHW1TbUqOCWeBPNrYdhQwhF0udQNdOif1h.BzenriLPb06srK4W0nuGb78hQvgAhwjCR5k_M2NxlK6a9PpdDkKlj_Po_joHxn0aDEvRVF4n0vm.0w.QPYLfXHfmFCQdnAnhA4gUvx1Y.Rc273n8DK7hl1.HCT6VBGHdisz14d2yXaRwnI.ORMVd5zodQl4hAJjLrb3vzzNwKnymjmlcTbNS7KTRonwo947yOX3gfY3TPG_2e411ltevcX3tNF6kJoH_cBrK7__3oGXEsYDmOtyILD4wmbSJoar41XkoLSRl0TxsrrGlF6KuO13vix5XuYZSaQ1oSyQ3dDT0mas25_mhYnZZE1YSr5hxDyzY0Ix_wc7QrHXxoTNloyHTjYxndKQ7WlJ7zoqaw6.WWqV1izJF4wIqSy5LL2vKDIz_oPw5EPNHRiqe7I5s5RdRH0m0qW0nVqvoc_czq_ZGQK6Yy71YJ13tZvSXhmuH73xvF4f3UIOtKtKieDD4pSavGFui.BFH_cOhO93AfOMeasQVgBPrqfunuYKjr.LnzmYXroWvSlEUQ"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/g/orchestrate/chl_page/v1?ray=92b1dab1283948ee';window._cf_chl_opt.cOgUHash = location.hash === '' && location.href.indexOf('#') !== -1 ? '#' : location.hash;window._cf_chl_opt.cOgUQuery = location.search === '' && location.href.slice(0, location.href.length - window._cf_chl_opt.cOgUHash.length).indexOf('?') !== -1 ? '?' : location.search;if (window.history && window.history.replaceState) {var ogU = location.pathname + window._cf_chl_opt.cOgUQuery + window._cf_chl_opt.cOgUHash;history.replaceState(null, null, "\/doc\/rfc3236\/?__cf_chl_rt_tk=AZsOsZuh.YoKqvl_lyG0NSahsGh1ogHTtErR9ylGyYs-1743780702-1.0.1.1-79cCJL5B0JyUG5b4wVavt5RR7cShmzuSDANDfGIpz1U" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>