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What is Caching and How is a Website Cached?

  • By Gcore
  • May 23, 2023
  • 8 min read
What is Caching and How is a Website Cached?

Caching is a method of storing and accessing data to enhance an application’s or website’s performance. When a regular user visits a certain website for the first time, they may notice that it loads slowly. However, on subsequent visits, it loads more quickly. This is because the browser downloads all the website content during the first visit, so the next time the user visits the same website the content is ready and waiting, which speeds up page load times.

This is just one of the ways in which caching enhances the web browsing experience. Whether you’re an end user or a business owner, understanding caching can help you gain insights into its importance. If you own a business, caching can reveal ways to optimize your online presence and improve customer experience.

In this article we will explore what caching is, how a website is cached, look at its various types, and understand how and why it’s being used across different industries. By the end of this article, you’ll understand how caching can boost your online activities, benefiting you in multiple ways.

What Is Caching?

Caching is the process of storing copies of data or files in a temporary location known as a cache. A cache is a high-speed data storage layer that computers or devices use to quickly access frequently used data. The cached data is stored temporarily in memory or on disk to improve performance and reduce server load. Various software applications and systems use caching to enhance their performance.

If a user requests data that has already been stored in the cache, the cache can immediately provide the data without having to retrieve it from the original source. This results in a significant improvement in performance, particularly for frequently accessed data.

What Are Some Examples of Caching?

There are many different types of caching, but some of the most common include:

  • Web browsers: Web browsers use a cache to store website data, including HTML files, multimedia (such as images and videos,) and scripts. This enables faster website loading times for subsequent visits.
  • Domain name system (DNS): Caching allows DNS servers and clients to store DNS records locally for a specified period of time. By caching DNS records, DNS servers and resolvers can reduce the number of queries made to the authoritative DNS servers, resulting in faster and more efficient domain name resolution.
  • Content delivery network (CDN): The use of a cache stores content that is frequently accessed, resulting in reduced server load and latency. When a request is made, a local copy of the content is delivered from a nearby Point of Presence (PoP). This results in faster loading times and an improved user experience.
  • Computer systems: CPU cache memory is a type of temporary memory that is built into a computer’s processor chip. This feature enables faster access to often-used information by reducing the number of times the CPU needs to access slower types of memory.
  • Content management systems (CMS): CMS platforms—such as WordPress—leverage browser caching to enhance website performance by storing cached copies of static pages on a user’s local computer. This enables quick delivery of the cached files in response to any subsequent requests to the website.

What Are the Benefits of Caching?

Caching offers numerous advantages to individual users, network systems, and businesses, enhancing the overall digital experience. Let’s dive into the major advantages.

  • Faster web browsing: Caching speeds up web browsing by quickly accessing data from the cache instead of retrieving it from the original source each time, improving the overall browsing experience.
  • Reduced data usage: On mobile devices, caching improves performance by reducing data usage, particularly when using apps that require frequent data access.
  • Reduced network traffic: Caching reduces network traffic by storing copies of data closer to users. This can help to improve performance and reduce latency.
  • Reduced server load: Storing frequently accessed server data can reduce bandwidth usage, which, in turn, can lower hosting costs for high-traffic websites.
  • Improved reliability: Reliability is improved by caching because caching provides a backup copy of data. If the primary source of data becomes unavailable, the cache can be used to provide access to the data.

Now that we have covered what caching is and explored its advantages, let’s turn to how it operates.

How Does Caching Work?

We have already discussed what caching is, looked at examples of how it works, and understood its benefits. Now, let’s take a more in-depth look at how caching works behind the scenes.

  1. The user opens (“requests”) a web page—let’s say www.example.com—on their browser.
  2. The cache will check whether the requested asset—the webpage example.com—already exists. This could be either in the browser cache or the CDN.
  3. If the requested file is already stored in the cache memory, it is considered a cache hit, and the file is delivered from the cache, allowing the user to access the webpage quickly.
In a cache hit, the cache returns a response to the client
  1. When a requested file cannot be found in the cache during the asset request, it is called a cache miss. The asset will then be retrieved from its primary source, resulting in a slower loading time for the user.
In a cache miss, the asset cannot be retrieved from the caching server and must be returned by the primary source

While there may be some differences between providers, the overall procedure is fundamentally the same for most caching scenarios.

To fully understand the advantages of caching, we also need to delve into DNS and CDN caching. DNS, or Domain Name System, serves as the backbone of the internet, enabling users to enter a domain name (like www.example.com) into their browser and access their desired website via an IP address, which is a string of numbers or numbers and letters. A CDN, or content delivery network, is a geographically distributed network of servers that bring service physically closer to end users. CDN is a crucial web solution for business owners to ensure fast and optimal performance of their website or applications. Let’s look at how they relate to caching.

How Does a DNS Cache Optimize Internet Browsing?

DNS caching permits a server or client to store DNS records locally and utilize them again in the future if necessary. To accomplish this, a time-to-live (TTL) value is used for each DNS record. This value specifies for how long (in seconds) a DNS client or server can cache a record. Different applications have different policies for caching DNS data. For example, Chrome caches up to 1,000 records for one minute.

The DNS system involves several steps that must be completed before the website appears on the user’s screen. To learn about this process in depth, check out our comprehensive guide to DNS. Here’s a simplified version of how DNS works from the user’s perspective to help understand how DNS caching works.

  1. A user enters a website URL (like www.example.com) in the browser.
  2. The computer looks up the IP address for that website using a DNS server.
  3. The DNS server checks its cache to see if it already has the IP address.
  4. If the cache doesn’t have the IP address, the DNS server asks other “authoritative name servers” to help find the IP address.
  5. The authoritative name servers respond with the IP address and a time-to-live (TTL) value that indicates how long the DNS record should be cached.
  6. The DNS server caches the IP address and TTL value for a certain time based on its settings and the TTL value provided by the authoritative name server.
  7. When the DNS record expires, the DNS server will query the authoritative name server again to get the updated IP address and TTL value.
The DNS resolution and caching process

Now that we understand the significance of DNS caching in the functioning of the internet, it’s important to shift our attention to another crucial factor: the content delivery network (CDN). CDN plays a vital role in making the internet faster and more dependable.

How Does CDN Use Caching?

CDNs use caching servers to enhance the delivery of content to different locations across the globe. Imagine a network of servers spread worldwide that store website content. These servers are called Points of Presence (PoPs) or edge servers. By duplicating frequently requested content, CDNs can deliver content faster and reduce the load on websites and applications by serving content from nearby PoPs. To learn about CDN in more detail, check out our article about CDN.

Here is a simplified step-by-step process of how CDN caching works:

  1. A user requests content from a website by typing the URL into their browser.
  2. The request is sent to the nearest Point of Presence (PoP) server in the CDN.
  3. The PoP server checks if it has the requested content in its cache. If it does, it immediately sends it back to the user’s browser.
  4. If the PoP server doesn’t have the content in its cache, it forwards the request to the origin server where the content is stored.
  5. The origin server sends the content back to the PoP server, which sends it to the user’s browser and caches it for future requests.
  6. Other PoP servers in the CDN also cache the content, so if another user located near a different PoP requests the same content, it can be served from a PoP server closer to them, reducing latency and improving performance.
  7. The content is cached for a certain amount of time, based on the settings of the CDN and the website’s origin server. When the cache expires, the process repeats and the content can be served again from the origin server.
Relationship between users, PoPs, and origin server

CDN caching offers two huge benefits. Firstly, the CDN’s PoP/edge server handles a significant portion of web traffic by retrieving content from its cache. Hence, the origin server is not burdened by many requests. Secondly, if the origin server experiences problems, the content stored in the CDN’s cache will still be available to users. This enables website owners to troubleshoot issues with the origin server while the CDN seamlessly delivers content from its cache.

Use Cases of Caching in Different Industries

Let’s review some typical applications of caching in various industries, along with examples and benefits.

Industry/FieldUse caseReal Life ScenarioBenefits
E-commerceProduct pagesAn e-commerce website caches product pages that receive high traffic to reduce server load and improve page load times for users.Increased conversion rates, reduced server costs
Media StreamingVideo contentA media streaming service caches frequently watched videos to reduce buffering times and improve user experience.Faster video playback, reduced server load, improved user retention
FinanceFinancial dataA financial services firm caches frequently accessed financial data to reduce the time it takes for employees or users to access information such as stock prices, news, and market data.Increased productivity, reduced server costs, improved data security
GamingGame assetsA gaming company can store frequently accessed game assets, such as textures, models, and levels.Faster game load times, reduced server load, improved user experience
HealthcarePatient recordsA healthcare provider caches patient records such as frequently accessed medical data, patient records, test results, and imaging data.Improved patient care, increased productivity, reduced server costs
EducationEducational contentAn online education platform caches frequently accessed educational content such as course materials, lecture notes, and assignments.Enhanced website speed, improved engagement of professors and students, reduced server costs

How Do Gcore DNS Hosting and CDN Improve Internet Performance?

We leverage caching to enhance online businesses across industries. Our solutions, including DNS hosting and CDN, offer global, scalable, and cost-effective solutions that enable our clients to enjoy fast websites, applications, and downloads. Let’s explore the features of Gcore’s DNS and CDN services and see how they can benefit website and business owners.

DNS Hosting

Ensuring fast and reliable DNS hosting is a top priority for us. As we discussed above, DNS caching plays a crucial role in optimizing application and browsing speeds. At Gcore DNS Hosting, we focus on three key priorities:

  1. Superior performance: Global minimal response times guarantee that your applications load quickly and smoothly, meeting your users’ expectations for high-speed and hassle-free access.
  2. Mission-critical availability: Ensure the availability and responsiveness of your services in the event of DDoS attacks, maintenance errors, and other incidents.
  3. Improved productivity: Enhance your DevOps experience with an extensive API that includes various beneficial integrations, all readily available for deployment.

Gcore DNS Hosting is feature-rich, including the following benefits:

  • Anycast Routing: To improve our DNS infrastructure on a global scale, we utilize Anycast routing. This method involves assigning the same IP to multiple servers located in different regions, enabling the closest server to promptly respond to all requests.
  • GeoDNS Functionality: Our DNS hosting service can help you to improve the performance of your online services by utilizing a GeoDNS mechanism. This provides customized DNS responses based on the location of the client, meaning that users to be directed to the nearest server based on their geographical location—a user in Asia is sent to an Asian server, whereas a user in Europe is sent to a European server.

Learn more about Gcore DNS hosting.

Next-Gen CDN

We’re all about speed and flexibility. With Gcore CDN, we make sure that your website performs lightning fast and reaches a global audience. To accelerate the speed of your website, applications, and downloads, our CDN offers:

  • Low latency worldwide: Our CDN Enables your app’s hosting to appear as if it’s always in the same location as your users, providing them with seamless access.
  • Dynamic content acceleration: Our dynamic content acceleration enhances your web applications’ performance, speeding up delivery time.
  • Outstanding availability: Our CDN effectively protects your server from being overloaded during unexpected traffic surges or DDoS attacks.

Earlier in this article, we discussed how CDN caching works and the importance of Point of Presence (PoP)/edge servers. At Gcore, we understand the significance of this, so we have invested in our global network to relieve you from the burden of purchasing expensive infrastructure. Here are some of our impressive statistics:

  • 140+ PoPs worldwide
  • 110+ Tbps network capacity
  • 85% average cache hit ratio
  • 2,000,000 request per seconds
  • 30 ms. average latency worldwide
  • 14 Tbps daily peak bandwidth

Learn more about Gcore CDN and check out our global network.

Conclusion

Caching stores frequently used data temporarily, reducing retrieval time from the source and improving website speed, application performance, and user experience. DNS and CDN are among the primary examples of this technology enabling fast online content access. DNS and CDN caching can help business owners increase website performance and reduce bounce rates, allowing regular users to enjoy faster website load times and a better browsing experience.

At Gcore, we understand that caching is crucial to performance. Gcore Next-Gen CDN and DNS Hosting leverage caching to improve website and application performance by reducing website load times and DNS lookup times. If you have questions or need a helping hand to get started, feel free to contact our experts; we’ll be happy to assist you.

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Flexible DDoS mitigation with BGP Flowspec cover image

Flexible DDoS mitigation with BGP Flowspec

For customers who understand their own network traffic patterns, rigid DDoS protection can be more of a limitation than a safeguard. That’s why Gcore supports BGP Flowspec: a flexible, standards-based method for defining granular filters that block or rate-limit malicious traffic in real time…before it reaches your infrastructure.In this article, we’ll walk through:What Flowspec is and how it worksThe specific filters and actions Gcore supportsCommon use cases, with example rule definitionsHow to activate and monitor Flowspec in your environmentWhat is the BGP Flowspec?BGP Flowspec (RFC 8955) extends Border Gateway Protocol to distribute traffic filtering rules alongside routing updates. Instead of static ACLs or reactive blackholing, Flowspec enables near-instantaneous propagation of mitigation rules across networks.BGP tells routers how to reach IP prefixes across the internet. With Flowspec, those same BGP announcements can now carry rules, not just routes. Each rule describes a pattern of traffic (e.g., TCP SYN packets >1000 bytes from a specific subnet) and what action to take (drop, rate-limit, mark, or redirect).What are the benefits of the BGP Flowspec?Most traditional DDoS protection services react to threats after they start, whether by blackholing traffic to a target IP, redirecting flows to a scrubbing center, or applying rigid, static filters. These approaches can block legitimate traffic, introduce latency, or be too slow to respond to fast-evolving attacks.Flowspec offers a more flexible alternative.Proactive mitigation: Instead of waiting for attacks, you can define known-bad traffic patterns ahead of time and block them instantly. Flowspec lets experienced operators prevent incidents before they start.Granular filtering: You’re not limited to blocking by IP or port. With Flowspec, you can match on packet size, TCP flags, ICMP codes, and more, enabling fine-tuned control that traditional ACLs or RTBH don’t support.Edge offloading: Filtering happens directly on Gcore’s routers, offloading your infrastructure and avoiding scrubbing latency.Real-time updates: Changes to rules are distributed across the network via BGP and take effect immediately, faster than manual intervention or standard blackholing.You still have the option to block traffic during an active attack, but with Flowspec, you gain the flexibility to protect services with minimal disruption and greater precision than conventional tools allow.Which parts of the Flowspec does Gcore implement?Gcore supports twelve filter types and four actions of the Flowspec.Supported filter typesGcore supports all 12 standard Flowspec match components.Filter FieldDescriptionDestination prefixTarget subnet (usually your service or app)Source prefixSource of traffic (e.g., attacker IP range)IP protocolTCP, UDP, ICMP, etc.Port / Source portMatch specific client or server portsDestination portMatch destination-side service portsICMP type/codeFilter echo requests, errors, etc.TCP flagsFilter packets by SYN, ACK, RST, FIN, combinationsPacket lengthFilter based on payload sizeDSCPQuality of service code pointFragmentMatch on packet fragmentation characteristicsSupported actionsGcore DDoS Protection supports the following Flowspec actions, which can be triggered when traffic matches a specific filter:ActionDescriptionTraffic-rate (0x8006)Throttle/rate limit traffic by byte-per-second rateredirectRedirect traffic to alternate location (e.g., scrubbing)traffic-markingApply DSCP marks for downstream classificationno-action (drop)Drop packets (rate-limit 0)Rule orderingRFC 5575 defines the implicit order of Flowspec rules. The crucial point is that more specific announcements take preference, not the order in which the rules are propagated.Gcore also respects Flowspec rule ordering per RFC 5575. More specific filters override broader ones. Future support for Flowspec v2 (with explicit ordering) is under consideration, pending vendor adoption.Blackholing and extended blackholing (eBH)Remote-triggered blackhole (RTBH) is a standardized protection method that the client manages via BGP by analyzing traffic, identifying the direction of the attack (i.e., the destination IP address). This method protects against volumetric attacks.Customers using Gcore IP Transit can trigger immediate blackholing for attacked prefixes via BGP, using the well-known blackhole community tag 65000:666. All traffic to that destination IP is dropped at Gcore’s edge.The list of supported BGP communities is available here.BGP extended blackholeExtended blackhole (eBH) allows for more granular blackholing that does not affect legitimate traffic. For customers unable to implement Flowspec directly, Gcore supports eBH. You announce target prefixes with pre-agreed BGP communities, and Gcore translates them into Flowspec mitigations.To configure this option, contact our NOC at noc@gcore.lu.Monitoring and limitationsGcore can support several logging transports, including mail and Slack.If the number of Flowspec prefixes exceeds the configured limit, Gcore DDoS Protection stops accepting new announcements, but BGP sessions and existing prefixes will stay active. Gcore will receive a notification that you reached the limit.How to activateActivation takes just two steps:Define rules on your edge router using Flowspec NLRI formatAnnounce rules via BGP to Gcore’s intermediate control planeThen, Gcore validates and propagates the filters to border routers. Filters are installed on edge devices and take effect immediately.If attack patterns are unknown, you’ll first need to detect anomalies using your existing monitoring stack, then define the appropriate Flowspec rules.Need help activating Flowspec? Get in touch via our 24/7 support channels and our experts will be glad to assist.Set up GRE and benefit from Flowspec today

Tuning Gcore CDN rules for dynamic application data caching

Caching services like a CDN service can be a solid addition to your web stack. They lower response latency and improve user experience while also helping protect your origin servers through security features like access control lists (ACLs) and traffic filtering. However, if you’re running a highly dynamic web service, a misconfigured CDN might lead to the delivery of stale or, in the worst case, wrong data.If you’re hosting a dynamic web service and want to speed it up, this guide is for you. It explains the common issues dynamic services have with CDNs and how to solve them with Gcore CDN.How does dynamic data differ from static data?There are two main differences between static and dynamic data:Change frequency: Dynamic data changes more often than static data. Some websites stay the same for weeks or months; others change multiple times daily.Personalized responses: Static systems deliver the same response for a given URL path. Dynamic systems, by contrast, can generate different responses for each user, based on parameters like authentication, location, session data, or user preferences.Now, you might ask: Aren’t static websites simply HTML pages while dynamic ones are generated on-the-fly by application servers?It depends.A website consisting only of HTML pages might still be dynamic if the pages are changed frequently, and an application server that generates HTML responses can serve the same HTML forever and always provide everyone with the same content for a URL. The CDN network doesn’t know how you create the HTML. It only sees the finished product and decides how long it should cache it. You need to decide on a case-by-case basis.How do cache rules affect dynamic data?When using a CDN, you have to define rules that govern the caching of your data. If you consider this data dynamic, either because it changes frequently or because you deliver user-specific responses, those rules can drastically impact the user experience, ranging from the delivery of stale data to completely wrong data.Cache expirationFirst, consider cache expiration time. With Gcore CDN, you have two options:Let your origin server control it. This is ideal for dynamic systems using application servers because it gives you precise control without needing to adjust Gcore settings.Let Gcore CDN control it. This works well for static HTTP servers delivering HTML pages that change often. If you can’t modify the server’s cache configuration, using Gcore’s settings is easier.No matter which method you choose, understand what your users consider “stale” and set the expiration time accordingly.Query string handlingNext, decide how Gcore CDN should handle URL query parameters. Ignoring them can improve performance—but for dynamic systems that use query strings for server-side sorting, filtering, or pagination, this can break functionality.For example, a headless CMS might use: https://example.com/api/posts?sort=asc&start=99If the CDN ignores the query string, it will always deliver the cached response, even if new parameters are requested. So, make sure to disable the Ignore query string parameters setting when necessary.Cookie bypassingCookies are often used for session handling. While ignoring cookies can boost performance, doing so risks breaking applications that rely on them.For example: https://example.com/api/users/profileIf this endpoint relies on a session cookie, caching without considering the cookie will serve the same user profile to everyone. Be sure to disable “Ignore cookies” if your server uses them for authentication or personalization.Cache key customizationIf you need more detailed control over the caching, you can modify the cache key generation. This key defines the mapping of a request to a cache entry and allows you to manage the granularity of your caching.The Gcore Customer Portal offers basic customization functionality, and the support team can help with advanced rules. For example, adding the request method (e.g., GET, HEAD, POST, etc.) to your cache key ensures a single URL has a dedicated cache entry for each method instead of using one for all.GraphQL considerationsMost GraphQL implementations only use POST requests and include the GraphQL query in the request body. This means every GraphQL request will use the same URL and the same method, regardless of the query. Gcore CDN doesn’t check the request body when caching, so every query will result in the same cache key and override each other.To make sure the CDN doesn’t break your API, turn off caching for all your GraphQL endpoints.Path-based CDN rules for hybrid contentIf your application serves both static and dynamic content across different paths, Gcore CDN rules offer a powerful way to manage caching more granularly.Using the CDN rules engine, you can create specific rules for individual file paths or extensions. This allows you to apply dynamic-appropriate settings—like disabling caching or respecting cookies—only to dynamic endpoints (e.g., /api/**), while using more aggressive caching for static assets (e.g., /assets/**, /images/**, or /js/**).This path-level control delivers performance gains from CDN caching without compromising the correctness of dynamic content delivery.SummaryUsing a CDN is an easy way to improve your site’s performance, and even dynamic applications can benefit from CDN caching when configured correctly. Check that:Expiration times reflect real-world freshness needsQuery strings and cookies aren’t ignored if they affect the responseCache keys are customized where neededGraphQL endpoints are excluded from cachingCDN rules are used to apply different settings for dynamic and static pathsWith the right setup, you can safely speed up even the most complex applications.Explore our step-by-step guide to setting rules for particular files in Gcore CDN.Discover Gcore CDN

How AI is reshaping the future of interactive streaming

Interactive streaming is entering a new era. Artificial intelligence is changing how live content is created, delivered, and experienced. Advances in real-time avatars, voice synthesis, deepfake rendering, and ultra-low-latency delivery are giving rise to new formats and expectations.Viewers don’t want to be passive audiences anymore. They want to interact, influence, and participate. For platforms that want to lead, the stakes are growing: innovate now, or fall behind.At Gcore, we support this shift with global streaming infrastructure built to handle responsive, AI-driven content at scale. This article explores how real-time interactivity is evolving and how you can prepare for what’s next.A new era for live contentStreaming used to mean watching someone else perform. Today, it’s becoming a conversation between the creator and the viewer. AI tools are making live content more reactive and personalized. A cooking show host can take ingredient requests from the audience and generate live recipes. A language tutor can assess student pronunciation and adjust the lesson plan on the spot. These aren’t speculative use cases—they’re already being piloted.Traditional cameras and presenters are no longer required. Some creators now use entirely digital hosts, powered by motion capture and generative AI. They can stream with multiple personas, switch backgrounds on command, or pause for mid-session translations. This evolution is not about replacing humans but creating new ways to engage that scale across time zones, languages, and platforms.Creating virtual influencersVirtual influencers are digital characters designed to build audiences, promote products, and hold conversations with followers. Unlike human influencers, they don’t get tired, change jobs, or need extensive re-shoots when messaging changes. They’re fully programmable, and the most successful ones are backed by teams of writers, animators, and brand strategists.For example, a skincare company might launch a virtual influencer with a consistent tone, recognizable look, and 24/7 availability. This persona could host product tutorials in the morning, respond to DMs during the day, and livestream reactions to customer feedback at night—all in the local language of the audience.These characters are not limited to influencer marketing. A virtual celebrity might appear as a guest at a live product launch or provide commentary during a sports event. The point is consistency, scalability, and control. Gcore’s global delivery network ensures these digital personas perform without delay, wherever the audience is located.Real-time avatars and AI-generated personasReal-time avatars use motion capture and emotion detection to mimic human behavior with digital models. A fitness instructor can appear as a stylized avatar while tracking their own real movements. A virtual talk show host can gesture, smile, or pause in response to viewer comments. These avatars do more than just look the part—they respond dynamically.AI-generated personas build on this foundation with language generation and decision-making. For instance, an edtech company could deploy a digital tutor that asks learners comprehension questions and adapts its tone based on their engagement level. In entertainment, a music artist might perform live as a virtual character that reflects audience mood through color shifts, dance patterns, or facial expression.These experiences require ultra-low latency. If the avatar lags, the illusion collapses. Gcore’s infrastructure supports the real-time input-output loop needed to make digital characters feel present and responsive.Deepfake technology for creative storytellingDeepfakes are often associated with misinformation, but the same tools can be used to build engaging, high-integrity content. The technology enables face-swapping, voice cloning, and character animation, all of which are powerful in live formats.A museum might use deepfake avatars of historical figures for interactive educational sessions. Visitors could ask questions, and Abraham Lincoln or Golda Meir might respond with historically grounded answers in real time. A brand could create a fictional spokesperson who evolves over time, appearing in product demos, ads, and livestreams. Deepfake technology also allows multilingual content without re-recording—the speaker’s lip movements and tone are modified to match each language.These applications raise legitimate ethical questions. Gcore’s streaming infrastructure includes controls to ensure the source and integrity of AI-generated content are traceable and secure. We provide the technical foundation that enables deepfake use cases without compromising trust.Synthetic voices and personalized audioAudio is often overlooked in discussions about AI streaming, but it’s just as important as video. Synthetic voices today can express subtle emotions and match speaking styles. They can whisper, shout, pause for dramatic effect, and even mimic regional accents.Let’s consider a news platform that offers interactive daily briefings. Viewers choose their preferred language, delivery style (casual, serious, humorous), and even the voice profile. The AI generates a personalized broadcast on the fly. In gaming, synthetic characters can offer encouragement, warn about strategy mistakes, or narrate progress—all without human voice actors.Gcore’s streaming infrastructure ensures that synthetic voice outputs are tightly synchronized with video, so users don’t experience out-of-sync dialogue or lag during back-and-forth exchanges.Increasing interactivity through feedback and participationInteractivity in streaming now goes far beyond comments or emoji reactions. It includes live polls that influence story outcomes, branching narratives based on audience behavior, and user-generated content layered into the broadcast.For example, a live talent show might allow viewers to suggest challenges mid-broadcast. An online classroom could let students vote on the next topic. A product launch might include a real-time Q&A where the host pulls questions from chat and answers them in the moment.All of these use cases rely on real-time data processing, behavior tracking, and adaptive rendering. Gcore’s platform handles the underlying complexity so that creators can focus on building experiences, not infrastructure.Why low latency is criticalInteractive content only works if it feels immediate. A delay of even a second can break immersion, especially when users are trying to influence the outcome or receive a response. Low latency is essential for real-time gaming, sports, interviews, and educational formats.A live trivia game with hundreds of participants won’t retain users if there’s a lag between the question appearing and the timer starting. A remote surgery training session won’t work if the avatar’s responses trail behind the mentor’s instructions. In each of these cases, timing is everything.Gcore Video Streaming minimizes buffering, supports high-resolution streams, and synchronizes data flows to keep participants engaged. Our infrastructure is built to support high-throughput, globally distributed audiences with the responsiveness that interactive formats demand.Preparing for what’s nextAI-generated content is no longer a novelty. It’s becoming a standard feature of modern streaming strategies. Whether you’re building a platform that features virtual influencers, immersive avatars, or interactive educational streams, the foundation matters. That foundation is infrastructure.If you’re planning the next generation of live content, we’re ready to help you bring it to life. At Gcore, we provide the performance, scale, and security to launch these experiences with confidence. Our streaming solutions are designed to support real-time content generation, audience interaction, and global delivery without compromise.Want to see interactive streaming in action? Learn how fan.at used Gcore Video Streaming to deliver ultra-low-latency streams and boost fan engagement with real-time features.Read the case study

What are captions and subtitles, and how do they work?

Subtitles and captions are essential to consuming video content today. But how do they work behind the scenes?Creating subtitles and captions involves a five-step process to ensure that your video’s spoken and auditory content is accurately and effectively conveyed. The five steps are transcription, correction, synchronization/spotting, translation, and simulation/display on screen.The whole process is usually managed using specialized subtitle or caption creator software.In this blog, we explain the five steps in more detail, what the end user sees, and how to choose the right caption/subtitle service for your needs.Step 1: TranscriptionSpoken content is transformed into a text-based format. Formats are different ways to implement the textual elements, depending on technical needs.Transcription creates the raw materials that will be refined in stages 2–4.Step 2: CorrectionCorrection enhances readability by improving the textual flow. Punctuation, grammar, and sentence structure are adjusted so that the user’s reading experience is seamless and doesn’t detract from the content.Step 3: Synchronization/spottingNext, the text and audio are aligned precisely. Each caption or subtitle’s timing is adjusted so it appears and disappears at the correct moment.Step 4: TranslationTranslation is required for content intended for consumption in multiple languages. During this stage, it’s important to consider format requirements and character limitations. For example, a caption that fits on two lines in English might require three in Spanish, and so in Spanish, one caption becomes two. As a result, additional synchronization might be necessary.Step 5: Simulation/display on screenFinally, the captions or subtitles need to be integrated onto the end user’s screen. Formatting issues might arise at this stage, requiring tweaks for an optimal user experience.How does the end user see subtitles and captions?After the technical process of creating captions and subtitles, the next step is understanding how these elements appear to the end user. The type of captions you choose can greatly impact the user experience, especially when considering accessibility, engagement, and clarity. Below, we break down the different options available and how they serve different viewing scenarios.Open captions: These are always visible to viewers and are a fixed part of the video. They’re popular, for example, for video installations in museums and employee training videos—cases where maximum accessibility is the key consideration when it comes to captions and/or subtitles.Closed captions: Viewers can turn these on or off based on preference. For instance, an online course might offer this feature, allowing learners to choose how to consume the content. Students could opt temporarily to turn on closed captions to note the spelling of a new term introduced during the course.Real-time captions: These are great for live events like webinars, where the text appears almost simultaneously as the words are spoken. They keep the audience engaged in real time without missing out on crucial points. For example, ambient noise like chatter in a sports bar might obscure commentary on a live TV basketball game. Real-time captions allow viewers to benefit from near-live commentary regardless of the bar’s noise levels or if the TV’s sound is muted.Burned-in subtitles: These are etched onto the video and cannot be turned off. A promotional video targeting a multilingual audience might use this feature so that everyone understands the message, regardless of their language preference.What to look for in captioning and subtitling servicesTo deliver high-quality captions and subtitles, it's important to choose a provider that offers key features for accuracy, efficiency, and audience engagement.Original language transcription: Accurate documentation of every spoken word in your video for unrivaled accuracy.Tailored translation: Localized content that integrates translations with cultural relevance, increasing resonance with diverse audiences.Alignment synchronization: Time-annotated subtitles, matching words perfectly to the on-screen action.Automatic SRT file generation: A simplified subtitling and captioning process through effortless file creation for a better user experience.Transform your videos with cutting-edge captions and subtitles from GcoreNo matter your video content needs, it’s essential to be aware of the best type of captions and subtitles for your audience’s needs. Choosing the right format ensures a smoother viewing experience, better accessibility, and stronger engagement across every platform.Gcore Video Streaming offers subtitles and closed captions to enhance users’ experience. Each feature within the subtitling and captioning toolkit is crafted to expand your video content’s reach and impact, catering to a multitude of use cases. Embedding captions is quick and easy, and AI-automated speech recognition also saves you time and money.Try Gcore's automated subtitle and caption solution for free

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