{"id":2374,"date":"2026-09-18T08:00:00","date_gmt":"2026-09-18T07:00:00","guid":{"rendered":"https:\/\/ic-services.io\/?p=2374"},"modified":"2026-09-17T18:07:44","modified_gmt":"2026-09-17T17:07:44","slug":"%ec%8b%ac%ec%b8%b5-%ed%8c%a8%ed%82%b7-%eb%b6%84%ec%84%9ddpi-lea-tls-%ec%a7%80%eb%ac%b8-%eb%b6%84%ec%84%9d","status":"publish","type":"post","link":"https:\/\/ic-services.io\/ko\/resources\/blog\/deep-packet-inspection-lea-tls-fingerprinting\/","title":{"rendered":"\ubc95 \uc9d1\ud589 \uae30\uad00\uc744 \uc704\ud55c TLS \uc9c0\ubb38 \ubd84\uc11d \ubc0f DPI: \uc554\ud638\ud654\ub41c IP \ud1b5\uc2e0 \uac10\uccad \ub370\uc774\ud130 \ud574\uc11d\ud558\uae30"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\"><strong>TLS fingerprinting<\/strong> and <a href=\"https:\/\/ic-services.io\/solutions\/deep-packet-inspection\/\">deep packet inspection<\/a> (DPI) have become essential tools for law enforcement agencies that receive IP data through lawful interception. When a CSP delivers a target&#8217;s internet traffic to the agency&#8217;s monitoring facility, almost all of it is encrypted: HTTPS, QUIC, end-to-end encrypted messengers, VPNs and encrypted DNS. Content decoding alone no longer delivers results. Yet even encrypted traffic reveals a lot, including which application was used, when, how intensively, with which server infrastructure and in parallel with which other activities.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This article explains how DPI on the receiving side works, what TLS fingerprinting (JA3, JA4 and the JA4+ family) can and cannot do, and how traffic pattern recognition, IP registries and data correlation turn raw packets into evidence-ready insights.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"key-takeaways\">Key Takeaways<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>DPI in a LEMF has two jobs: <strong>decode<\/strong> whatever is still readable, and <strong>classify<\/strong> everything that is not.<\/li>\n\n\n<li><strong>TLS fingerprinting<\/strong> identifies client software (apps, browsers, libraries, malware) and server stacks from handshake parameters, without decrypting anything.<\/li>\n\n\n<li><strong>JA4<\/strong> replaced JA3 as the de facto standard, because browsers now randomise TLS extension order, which breaks JA3 hashes.<\/li>\n\n\n<li><strong>Traffic pattern recognition<\/strong> (packet sizes, timing, bursts) can distinguish a text message from a voice call or a file upload, even inside end-to-end encrypted apps.<\/li>\n\n\n<li>An <strong>IP registry<\/strong> (IP \u2192 service, ASN, domain, certificate, geolocation, first\/last seen) combined with <strong>cross-target correlation<\/strong> helps reveal contact points and communication hypotheses.<\/li>\n\n\n<li>Every classifier must be versioned, explainable and limited to the scope of the warrant, or the results will not hold up in court.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"why-content-decoding-is-no-longer-enough\">Why Content Decoding Is No Longer Enough<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A decade ago, an IP intercept could be rebuilt into web pages, webmail and chat messages. Today, several developments have changed the picture:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>TLS 1.3<\/strong> encrypts most of the handshake, including the server certificate.<\/li>\n\n\n<li><strong>QUIC \/ HTTP\/3<\/strong> moves web traffic onto encrypted UDP.<\/li>\n\n\n<li><strong>End-to-end encrypted messengers<\/strong> protect content even from their own operators.<\/li>\n\n\n<li><strong>DNS over HTTPS (DoH) and DNS over TLS (DoT)<\/strong> hide domain lookups. See our article on <a href=\"https:\/\/ic-services.io\/resources\/blog\/encrypted-dns-doh-dot-li-impact\/\">encrypted DNS and lawful interception<\/a>.<\/li>\n\n\n<li><strong>VPNs, proxies and Tor<\/strong> hide the final destination.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">As a result, agencies no longer expect a monitoring facility to stop at protocol decoding. Traffic that cannot be decoded should at least be <strong>classified by continuously updated DPI<\/strong>. Analysts want to see which communication service was used and how much data it generated in a given period, and they want to adjust the classification rules themselves.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"what-dpi-and-tls-fingerprinting-can-still-see-in-encrypted-traffic\">What DPI and TLS Fingerprinting Can Still See in Encrypted Traffic<\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead>\n<tr>\n<th>Signal<\/th>\n<th>What it reveals<\/th>\n<th>Limitations<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>IP addresses, ports, ASN<\/td>\n<td>Server infrastructure, cloud or CDN provider, VPN endpoints<\/td>\n<td>Shared CDN IPs serve many services<\/td>\n<\/tr>\n<tr>\n<td>DNS (if unencrypted)<\/td>\n<td>Domains the target looked up<\/td>\n<td>DoH\/DoT hide lookups<\/td>\n<\/tr>\n<tr>\n<td>TLS SNI<\/td>\n<td>Server name requested by the client<\/td>\n<td>Can be hidden by ECH or made misleading by domain fronting<\/td>\n<\/tr>\n<tr>\n<td>ALPN, TLS version, cipher suites<\/td>\n<td>Protocol stack and client type<\/td>\n<td>Needs fingerprinting to interpret<\/td>\n<\/tr>\n<tr>\n<td>Server certificate (TLS 1.2)<\/td>\n<td>Organisation, domain, issuer<\/td>\n<td>Encrypted in TLS 1.3<\/td>\n<\/tr>\n<tr>\n<td>QUIC Initial packets<\/td>\n<td>SNI and client parameters (decryptable Initial keys)<\/td>\n<td>Later packets fully encrypted<\/td>\n<\/tr>\n<tr>\n<td>Packet sizes and timing<\/td>\n<td>Activity type: text, voice, video, file transfer<\/td>\n<td>Requires trained models<\/td>\n<\/tr>\n<tr>\n<td>Flow volumes and duration<\/td>\n<td>Usage intensity and time patterns<\/td>\n<td>Needs context to interpret<\/td>\n<\/tr>\n<tr>\n<td>STUN\/TURN and relay traffic<\/td>\n<td>Real-time calls and peer-to-peer media<\/td>\n<td>App-specific<\/td>\n<\/tr>\n<\/tbody><\/table><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"tls-fingerprinting-explained-from-ja3-to-ja4\">TLS Fingerprinting Explained: From JA3 to JA4+<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Every TLS client (a browser, an app, a malware family, a command-line tool) builds its <strong>ClientHello<\/strong> in a characteristic way: TLS version, cipher suites, extensions, supported groups, signature algorithms and ALPN values. A fingerprint condenses these parameters into a short, comparable string.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"ja3-the-original\">JA3: The Original<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">JA3 concatenated the ClientHello fields and hashed them with MD5. It was widely used for years. Its weakness became obvious when major browsers started to <strong>randomise the order of TLS extensions<\/strong> in 2023, so the same browser now produces many different JA3 hashes.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"ja4-the-new-standard\">JA4: The New Standard<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>JA4<\/strong>, published by FoxIO, sorts the relevant values before hashing and uses a human-readable prefix. The prefix encodes the transport (TCP or QUIC), TLS version, SNI presence, number of ciphers and extensions, and the first application protocol (ALPN) value the client offers. Extension randomisation therefore no longer breaks the fingerprint, and analysts can read part of it without a lookup table. JA4 itself is released under the BSD 3-Clause licence.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"the-ja4-family\">The JA4+ Family<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">JA4 is part of a wider suite (JA4+) that covers more than the client handshake:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>JA4S<\/strong>: fingerprints the server&#8217;s response and helps identify server applications and infrastructure.<\/li>\n\n\n<li><strong>JA4X<\/strong>: characterises <em>how<\/em> TLS certificates were generated, which is useful for spotting self-signed or tool-generated infrastructure.<\/li>\n\n\n<li><strong>JA4H<\/strong>: fingerprints HTTP client requests.<\/li>\n\n\n<li><strong>JA4L<\/strong>: estimates latency and distance from handshake timing.<\/li>\n\n\n<li><strong>JA4SSH<\/strong>: classifies SSH session behaviour, such as interactive use versus file transfer.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">All JA4+ methods other than JA4 are published under the FoxIO License 1.1. It allows internal use, but vendors need an OEM licence to include them in commercial products. LEMF vendors and buyers should check this.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"what-tls-fingerprinting-tells-an-investigator\">What TLS Fingerprinting Tells an Investigator<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Which <strong>application or library<\/strong> opened the connection (a specific messenger, a browser, a custom tool).<\/li>\n\n\n<li>Whether a target uses <strong>VPN clients, Tor or anonymisation tools<\/strong>.<\/li>\n\n\n<li>Whether several connections come from the <strong>same device or software stack<\/strong>, even if IP addresses change.<\/li>\n\n\n<li>Whether the server side matches known <strong>infrastructure patterns<\/strong>, for example the command-and-control servers of a malware family.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A fingerprint is a strong indicator, not proof of identity. Common libraries are shared by many apps, so fingerprints should always be combined with other signals.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"traffic-pattern-recognition-inside-encrypted-apps\">Traffic Pattern Recognition Inside Encrypted Apps<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Even when both content and server names are hidden, the <strong>shape<\/strong> of the traffic remains visible:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Text messages<\/strong> create short bursts of small packets followed by acknowledgements and read receipts.<\/li>\n\n\n<li><strong>Voice and video calls<\/strong> create continuous, evenly spaced UDP streams, often after a STUN\/TURN exchange.<\/li>\n\n\n<li><strong>Media and file transfers<\/strong> create sustained high-volume uploads or downloads.<\/li>\n\n\n<li><strong>Push notifications and keep-alives<\/strong> follow periodic, app-specific rhythms.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Machine-learning classifiers trained on packet length sequences, inter-arrival times and burst statistics can label these activities with high accuracy. For the analyst, the result is an <strong>event timeline<\/strong>: &#8220;08:14 message sent via messenger A, 08:16 voice call of 4 minutes, 08:31 upload of approx. 12 MB&#8221;. This is valuable even though the content itself stays unknown.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"ip-registry-and-data-correlation\">IP Registry and Data Correlation<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Classification becomes intelligence once it is correlated. A modern LEMF maintains an <strong>IP registry<\/strong> for each case and across cases:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>IP-to-service resolution<\/strong>: which service, cloud provider or CDN is behind an address, enriched with ASN, reverse DNS, passive DNS, certificate transparency data and geolocation.<\/li>\n\n\n<li><strong>First seen \/ last seen<\/strong> for every remote address and fingerprint per target.<\/li>\n\n\n<li><strong>Watch lists<\/strong> of IP addresses, domains and fingerprints of interest, which trigger alerts.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">On top of this registry, correlation techniques reveal connections that no single data point shows:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Common contact points<\/strong>: several targets that communicate with the same rare server, VPN endpoint or self-hosted service.<\/li>\n\n\n<li><strong>Temporal correlation<\/strong>: activity that starts and stops at the same time on two targets suggests a communication between them, even through an encrypted messenger.<\/li>\n\n\n<li><strong>Device continuity<\/strong>: identical fingerprints across different lines or SIM cards point to the same device or user.<\/li>\n\n\n<li><strong>IRI linkage<\/strong>: combining IP events with HI2 location data, cell IDs and device identifiers (IMEI) shows where an activity took place.<\/li>\n\n\n<li><strong>Subscriber identification<\/strong>: public IP addresses and ports observed in third-party data (for example from a platform provider) can be traced back to a subscriber through a lawful request to the access provider. This is exactly what the planned German <a href=\"https:\/\/ic-services.io\/solutions\/data-retention\/\">IP address retention<\/a> obligation is designed to support.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">The results are visualised as timelines, maps and relationship graphs, and they feed rule-based alerts.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"a-typical-dpi-workflow-in-the-lemf\">A Typical DPI Workflow in the LEMF<\/h2>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Ingest<\/strong> HI3 IP deliveries (ETSI TS 102 232-3 for internet access, -7 for mobile) and the matching HI2 records.<\/li>\n\n\n<li><strong>Sessionise<\/strong> packets into flows and sessions, including across IP address changes.<\/li>\n\n\n<li><strong>Decode<\/strong> readable protocols and reconstruct products (web, e-mail, files, VoIP).<\/li>\n\n\n<li><strong>Classify<\/strong> the remaining traffic with DPI signatures, TLS fingerprinting and behavioural models.<\/li>\n\n\n<li><strong>Enrich<\/strong> with the IP registry, geolocation and IRI data.<\/li>\n\n\n<li><strong>Correlate<\/strong> across targets, cases and time.<\/li>\n\n\n<li><strong>Visualise and alert<\/strong> in the analyst workbench, with drill-down to the raw PCAP.<\/li>\n\n\n<li><strong>Document<\/strong> the decoder and classifier versions used for every result.<\/li>\n<\/ol>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"legal-and-evidential-boundaries\">Legal and Evidential Boundaries<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">DPI in law enforcement operates under strict legal limits:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Analysis must stay within the <strong>scope of the warrant<\/strong> and the measures an analyst is authorised for.<\/li>\n\n\n<li><strong>Proportionality and data protection<\/strong> rules (in the EU, the Law Enforcement Directive (EU) 2016\/680 and national criminal procedure law) apply to every processing step.<\/li>\n\n\n<li>Classification results are <strong>indicators<\/strong>. Their error rates must be known, documented and explainable to a court.<\/li>\n\n\n<li><strong>Versioning<\/strong> is mandatory. If a classifier is updated and data is re-analysed, the original result must remain visible.<\/li>\n\n\n<li><strong>Privileged communications<\/strong> must be flaggable and lockable.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"buyers-checklist-for-dpi-in-a-lemf\">Buyer&#8217;s Checklist for DPI in a LEMF<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Continuously updated DPI signatures with a documented update cycle<\/li>\n\n\n<li>Agency-adjustable classification rules<\/li>\n\n\n<li>Per-application volume and time display for encrypted services<\/li>\n\n\n<li>JA4-based TLS fingerprinting with proper licensing<\/li>\n\n\n<li>Behavioural classification of activity types (message, call, transfer)<\/li>\n\n\n<li>Case-level and cross-case IP registry with watch lists<\/li>\n\n\n<li>Correlation with IRI, location and subscriber data<\/li>\n\n\n<li>Decoder and classifier plugin API with a sandboxed test framework<\/li>\n\n\n<li>PCAP export to external tools such as Wireshark<\/li>\n\n\n<li>Full versioning and audit trail<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"how-ics-helps\">How ICS Helps<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">ICS International Carrier Services combines <strong>more than 20 years of experience in telecommunications, lawful interception and compliance<\/strong> with hands-on IP expertise on both sides of the handover interface. Our team analyses VoLTE, IMS and IP traces every day and holds <strong>multiple BNetzA acceptances<\/strong> for interception solutions.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>DPI in ICS LEMF<\/strong>: classification, TLS fingerprinting, IP registry and correlation are built into our monitoring facility software. See <a href=\"https:\/\/ic-services.io\/solutions\/deep-packet-inspection\/dpi-for-law-enforcement\/\">DPI for Law Enforcement<\/a> and <a href=\"https:\/\/ic-services.io\/products\/software-solutions\/law-enforcement-monitoring-facility\/\">ICS LEMF<\/a>.<\/li>\n\n\n<li><strong>DPI and analytics requirements<\/strong>: we help agencies write precise, testable requirements for DPI, fingerprinting and correlation in LEMF tenders.<\/li>\n\n\n<li><strong>Custom decoders and classifiers<\/strong>: development of protocol decoders, classification modules and enrichment pipelines. See <a href=\"https:\/\/ic-services.io\/services\/integration-custom-development\/\">Integration &amp; Custom Development<\/a>.<\/li>\n\n\n<li><strong>Delivery validation<\/strong>: making sure ETSI TS 102 232 IP deliveries from CSPs are complete and analysable before they reach your analysts.<\/li>\n\n\n<li><strong>Training<\/strong> for analysts and technical teams on encrypted traffic analysis and its limits.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Talk to us about your IP analytics challenges. <a href=\"https:\/\/ic-services.io\/contact\/\">Contact ICS<\/a> or learn more about our <a href=\"https:\/\/ic-services.io\/industries\/law-enforcement-interception\/\">support for law enforcement and regulators<\/a>.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"frequently-asked-questions\">Frequently Asked Questions<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"what-is-tls-fingerprinting\">What is TLS fingerprinting?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">TLS fingerprinting derives a compact identifier from the parameters a client or server uses in the TLS handshake, such as version, cipher suites, extensions and ALPN. It identifies the software behind a connection without decrypting the traffic.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"what-is-the-difference-between-ja3-and-ja4\">What is the difference between JA3 and JA4?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">JA3 hashes the ClientHello fields in the order they appear, so browsers that randomise extension order produce changing hashes. JA4 sorts the values before hashing and adds a readable prefix, which makes it stable and easier to interpret.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"can-law-enforcement-decrypt-whatsapp-or-signal-traffic-with-dpi\">Can law enforcement decrypt WhatsApp or Signal traffic with DPI?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">No. DPI does not break end-to-end encryption. It can identify that such an app was used, when, for how long and with how much data, and it can often tell a message from a call. Content access requires other legal instruments.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"is-deep-packet-inspection-legal-for-law-enforcement\">Is deep packet inspection legal for law enforcement?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">DPI of intercepted traffic is lawful when it is covered by a valid interception order and performed within the limits of national criminal procedure and data protection law. The analysis must remain within the scope of the order and be documented.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"what-is-an-ip-registry-in-lawful-interception\">What is an IP registry in lawful interception?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">An IP registry is a case-level database of the remote IP addresses, domains and fingerprints observed in intercepted traffic. It is enriched with service, ASN and geolocation data and records when each item was first and last seen. It is the basis for correlation and alerts.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"related-articles\">Related Articles<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/ic-services.io\/resources\/blog\/encrypted-dns-doh-dot-li-impact\/\">Encrypted DNS (DoH\/DoT) and Its Impact on Lawful Interception Capabilities<\/a><\/li>\n\n\n<li><a href=\"https:\/\/ic-services.io\/resources\/blog\/ai-lawful-interception-automation\/\">AI-Assisted LI: What Automation Means for Operators and Law Enforcement Workflows<\/a><\/li>\n\n\n<li><a href=\"https:\/\/ic-services.io\/resources\/blog\/iri-vs-cc-intercept-related-information\/\">IRI vs CC: What Intercept-Related Information Actually Means in Practice<\/a><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"external-resources\">External Resources<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/blog.foxio.io\/ja4+-network-fingerprinting\" rel=\"noopener noreferrer\" target=\"_blank\">FoxIO: JA4+ Network Fingerprinting<\/a><\/li>\n\n\n<li><a href=\"https:\/\/www.etsi.org\/technologies\/lawful-interception\" rel=\"noopener noreferrer\" target=\"_blank\">ETSI Lawful Interception Standards (TC LI)<\/a><\/li>\n\n\n<li><a href=\"https:\/\/eur-lex.europa.eu\/eli\/dir\/2016\/680\/oj\" rel=\"noopener noreferrer\" target=\"_blank\">Directive (EU) 2016\/680 (Law Enforcement Directive)<\/a><\/li>\n<\/ul>\n\n\n\n<script type=\"application\/ld+json\">{\"@context\": \"https:\/\/schema.org\", \"@type\": \"FAQPage\", \"mainEntity\": [{\"@type\": \"Question\", \"name\": \"What is TLS fingerprinting?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"TLS fingerprinting derives a compact identifier from the parameters a client or server uses in the TLS handshake, such as version, cipher suites, extensions and ALPN. It identifies the software behind a connection without decrypting the traffic.\"}}, {\"@type\": \"Question\", \"name\": \"What is the difference between JA3 and JA4?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"JA3 hashes the ClientHello fields in the order they appear, so browsers that randomise extension order produce changing hashes. JA4 sorts the values before hashing and adds a readable prefix, which makes it stable and easier to interpret.\"}}, {\"@type\": \"Question\", \"name\": \"Can law enforcement decrypt WhatsApp or Signal traffic with DPI?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"No. DPI does not break end-to-end encryption. It can identify that such an app was used, when, for how long and with how much data, and it can often tell a message from a call. 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It is the basis for correlation and alerts.\"}}]}<\/script>\n","protected":false},"excerpt":{"rendered":"<p>\uac10\uccad\ub41c IP \ud2b8\ub798\ud53d\uc758 \ub300\ubd80\ubd84\uc740 \uc554\ud638\ud654\ub418\uc5b4 \uc788\uc2b5\ub2c8\ub2e4. \ubc95 \uc9d1\ud589 \uae30\uad00\uc774 \ub525 \ud328\ud0b7 \uac80\uc0ac, TLS \uc9c0\ubb38 \ubd84\uc11d(JA4), \ud2b8\ub798\ud53d \ud328\ud134 \uc778\uc2dd \ubc0f IP \uc0c1\uad00 \ubd84\uc11d\uc744 \ud65c\uc6a9\ud558\uc5ec \uc554\ud638\ud654\ub41c \uac10\uccad \uc815\ubcf4\ub97c \uc720\uc6a9\ud55c \uc815\ubcf4\ub85c \uc804\ud658\ud558\ub294 \ubc29\ubc95\uc744 \uc54c\uc544\ubcf4\uc138\uc694.<\/p>","protected":false},"author":7,"featured_media":2584,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_uag_custom_page_level_css":"","site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center 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Son","author_link":"https:\/\/ic-services.io\/ko\/author\/david\/"},"uagb_comment_info":0,"uagb_excerpt":"Most intercepted IP traffic is encrypted. Learn how law enforcement agencies use deep packet inspection, TLS fingerprinting (JA4), traffic pattern recognition and IP correlation to turn encrypted intercepts into usable intelligence.","_links":{"self":[{"href":"https:\/\/ic-services.io\/ko\/wp-json\/wp\/v2\/posts\/2374","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ic-services.io\/ko\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ic-services.io\/ko\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ic-services.io\/ko\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/ic-services.io\/ko\/wp-json\/wp\/v2\/comments?post=2374"}],"version-history":[{"count":3,"href":"https:\/\/ic-services.io\/ko\/wp-json\/wp\/v2\/posts\/2374\/revisions"}],"predecessor-version":[{"id":2482,"href":"https:\/\/ic-services.io\/ko\/wp-json\/wp\/v2\/posts\/2374\/revisions\/2482"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/ic-services.io\/ko\/wp-json\/wp\/v2\/media\/2584"}],"wp:attachment":[{"href":"https:\/\/ic-services.io\/ko\/wp-json\/wp\/v2\/media?parent=2374"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ic-services.io\/ko\/wp-json\/wp\/v2\/categories?post=2374"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ic-services.io\/ko\/wp-json\/wp\/v2\/tags?post=2374"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}