--- title: Techniques for real-time client-server communication on... description: Explains the fundamental challenge of HTTP's request/response model for real-time web communication, covering three workaround techniques: simple Ajax polling,... canonical: https://daily.dev/posts/techniques-for-real-time-client-server-communication-on-the-web-signalr-to-the-rescue--pnkms0oaj twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Techniques for real-time client-server communication on the web (SignalR to the rescue) | daily.dev og:description: Explains the fundamental challenge of HTTP's request/response model for real-time web communication, covering three workaround techniques: simple Ajax polling,... og:url: https://daily.dev/posts/techniques-for-real-time-client-server-communication-on-the-web-signalr-to-the-rescue--pnkms0oaj og:image: https://api.daily.dev/og/posts/PNkms0Oaj.png og:image:alt: Techniques for real-time client-server communication on the web (SignalR to the rescue) og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Techniques for real-time client-server communication on the web (SignalR to the rescue) **[Maarten Balliauw](https://daily.dev/sources/maartenballiauw)** · 5 min read · 0 upvotes · 0 comments ## Summary Explains the fundamental challenge of HTTP's request/response model for real-time web communication, covering three workaround techniques: simple Ajax polling, long polling, and HTML5 WebSockets, discussing their trade-offs and browser/infrastructure support limitations circa the draft WebSockets spec. Introduces SignalR, a Microsoft ASP.NET library that abstracts over all three techniques to let client JavaScript and server C# call each other's methods seamlessly, with a code example showing a simple hub-based hello-world across client and server. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What is the difference between Ajax polling and long polling for real-time web updates? Ajax polling has the client repeatedly request data at fixed intervals, so new server data waits until the next poll, hurting real-time responsiveness. Long polling instead keeps the Ajax connection open until the server has data, then immediately reopens it, eliminating the polling interval but requiring servers to handle many held-open connections, which can exhaust a thread pool unless async handlers are used. _daily.dev surfaces practical comparisons like this for developers deciding how to architect real-time features._ ### How does SignalR let JavaScript and C# code call each other's methods directly? SignalR hubs let a server-side C# class expose methods that JavaScript clients invoke directly, such as calling SayHelloToAll, while the server can call a JavaScript function like sayHelloToMe on connected clients as if it were a native C# method. SignalR automatically picks the underlying transport (polling, long polling, or WebSockets) based on what client and server support. _developers building real-time ASP.NET features can track libraries like SignalR as they evolve on daily.dev._ ## Similar posts on daily.dev - [Real-Time at Last: SSE and SignalR in ASP.NET Core](https://daily.dev/posts/real-time-at-last-sse-and-signalr-in-asp-net-core-hfyl1qquh) · We Are .NET · 0 upvotes · 0 comments - [HTML over WebSockets: real-time SPAs with barely any JavaScript](https://daily.dev/posts/html-over-websockets-real-time-spas-with-barely-any-javascript-xef6zsuxl) · Hacker News · 2 upvotes · 0 comments - [Server-Sent Events in ASP.NET Core and .NET 10](https://daily.dev/posts/server-sent-events-in-asp-net-core-and-net-10-rqln4wisb) · Milan Jovanović · 25 upvotes · 0 comments --- Tags: [#webdev](https://daily.dev/tags/webdev) [View this post on daily.dev](https://daily.dev/posts/techniques-for-real-time-client-server-communication-on-the-web-signalr-to-the-rescue--pnkms0oaj) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Techniques for real-time client-server communication on the web (SignalR to the rescue)","url":"https://daily.dev/posts/techniques-for-real-time-client-server-communication-on-the-web-signalr-to-the-rescue--pnkms0oaj","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/techniques-for-real-time-client-server-communication-on-the-web-signalr-to-the-rescue--pnkms0oaj"},"datePublished":"2026-10-04T13:05:46.036Z","dateModified":"2026-10-04T13:11:17.532Z","description":"Explains the fundamental challenge of HTTP's request/response model for real-time web communication, covering three workaround techniques: simple Ajax polling,...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/dcf46f7da70960a8c0828f21308f2261?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/dcf46f7da70960a8c0828f21308f2261?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Maarten Balliauw","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Maarten Balliauw","logo":"https://media.daily.dev/image/upload/s--rOTg3VYO--/f_auto,q_auto/v1791119043/logos/maartenballiauw?_a=BAMAMicg0","url":"https://daily.dev/sources/maartenballiauw"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/techniques-for-real-time-client-server-communication-on-the-web-signalr-to-the-rescue--pnkms0oaj","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"webdev","timeRequired":"PT5M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Maarten Balliauw","item":"https://daily.dev/sources/maartenballiauw"},{"@type":"ListItem","position":3,"name":"Techniques for real-time client-server communication on the web (SignalR to the rescue)"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/techniques-for-real-time-client-server-communication-on-the-web-signalr-to-the-rescue--pnkms0oaj#faq","mainEntity":[{"@type":"Question","name":"What is the difference between Ajax polling and long polling for real-time web updates?","acceptedAnswer":{"@type":"Answer","text":"Ajax polling has the client repeatedly request data at fixed intervals, so new server data waits until the next poll, hurting real-time responsiveness. 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