Web Conferencing

With remote and distributed work becoming increasingly popular, web conferencing has evolved to meet the demand for real-time communication across teams and time zones.

What Is Web Conferencing?

Web conferencing enables real-time online meetings between participants over the internet. It is broader than audio or video conferencing, as it often includes additional features like polling, Q&A, breakout rooms, and synchronized screen or slide sharing.

Most users think of it as services like Zoom, Meet, or Teams. However, companies can add the same capabilities to their products by building in-house or integrating APIs or SDKs. For example, a distance learning high school might host live classes over Zoom, but a startup would build or integrate conferencing features into its edtech app for deeper customization.

How Does Web Conferencing Work?

Under the hood, it combines media capture, encoding, transport, and session coordination. These key components include:

Media Capture and Encoding

This process starts when the participants' devices capture audio and video, with the browser or app accessing them via APIs like getUserMedia().

Because the raw feeds can exceed hundreds of megabytes, they are compressed using media codecs to reduce bandwidth before transmission. Common codecs include H.264 and VP8/9 for video and Opus for audio.

All participants' outgoing media gets encoded this way. The stream is then decoded and played back on the recipient's end.

Network Transport

After encoding, the media packets must be sent across the network to other participants over Real-Time Transport Protocol (RTP), typically via WebRTC. WebRTC establishes direct peer-to-peer connections between users' devices for exchanging media in real-time.

RTP adds sequence numbers to each packet, so receivers can reorder them and synchronize audio with video.

Conferencing tools often use another protocol, the Real-Time Transport Control Protocol (RTCP), which maintains audio and video synchronization and reports quality metrics such as packet loss, latency, and jitter. 

Signaling Server 

Users need to connect with each other on the conferencing solution before the media exchange. This process is known as signaling, where the system's signaling server coordinates the initial handshake between clients.

The signaling server manages the call setup and sessions. When a user joins a web conference, the application sends a session initiation request to the signaling server. The server then relays the connection messages, including the Session Description Protocol (SDP).

The SDP shares information such as the IP addresses, ports, expected media types, and the codes in use. It also handles participants' connections.

During signaling, peers exchange network information using Interactive Connectivity Establishment (ICE). A STUN server helps peers discover their public IP addresses and ports to facilitate direct connections. If a direct peer-to-peer connection fails due to firewall or NAT restrictions, a TURN server is used as a relay for routing media.

Media Servers

To handle web conferences with more than two participants, conferencing solutions use media servers. These are server-side components that manage media traffic, allowing additional processing (such as transcoding or recording) and efficient distribution.

Three primary architectures are used: MCU, SFU, and P2P.

• Multipoint Control Unit (MCU): The MCU receives streams from all devices connected to it, decodes them, and merges them into a single feed. It then re-encodes and sends one stream per participant.

MCUs synchronize different streams to ensure the participants hear each other at the same time. They use various algorithms to optimize the quality of media streams to reduce the bandwidth consumption. They also provide extra features like content sharing, screen sharing, streaming, and recording. However, while they greatly reduce bandwidth and processing burden on each client, they put a heavy load on the server.

• Selective Forwarding Unit (SFU): This is a different type of architecture, where each participant sends their media stream to a server, except that the server doesn't mix or transcode the media by default. Instead, it receives the streams and decides where to send them.

Unlike the MCU, SFU doesn't decode video. Each participant receives the streams of all connected devices and decodes them on their devices. It allows clients to adapt the quality of streams they receive.

Most modern conferencing solutions like Microsoft Teams, Zoom, and Google Meet use SFU or similar routing architectures due to their efficiency and scalability.

• Peer-to-Peer (P2P). This architecture has no media server. Participants exchange media streams directly without relying on centralized media servers. P2P still requires signaling servers for initial connection setup and STUN/TURN servers for NAT traversal. Due to bandwidth and computational constraints, this architecture is not scalable beyond small meetings.

Quality Management 

Networks often introduce packet loss, jitter, and bandwidth issues, which can degrade streams. To maintain call quality, modern conferencing systems monitor these conditions and dynamically adjust parameters like bitrate, frame rate, and resolution in real time.

Common techniques to improve stream quality include:

• Adaptive Bitrate Resolution (ABR). Adaptive bitrate adjusts bitrate, frame rate, or resolution based on observed packet loss and round-trip time to match the network's capacity. Participants receive varying stream quality depending on their available bandwidth, rather than a one-size-fits-all stream.

• Simulcast. This feature adjusts the video resolution or frame rate on the fly based on the receiving device's capabilities and network speed. Modern SFUs use simulcast, which, unlike ABR, lets each user receive the quality best suited to their setup concurrently from the same sender.

• Jitter Buffers and Error Correction. Real-time calls can degrade when packet timing varies (known as jitter) or latency is too high. To solve these problems, web conferencing apps use jitter buffers, which add a tiny delay to smooth out the arrival times of packets. They also use error correction techniques like packet loss concealment, which covers up missing packets and minimizes quality drops.

Key Features of Web Conferencing

Whether you're looking for an enterprise solution for internal meetings or considering adding conferencing to your app, these are some of the features that users expect:

Core Communication

Core communication features that deliver an effective virtual meeting experience include:

Audio and Video Calling

Real-time video and audio communication are at the heart of every web conferencing solution. A good system should deliver high-quality streams even under varying bandwidth conditions and have noise suppression and echo cancellation to enhance audio clarity and eliminate background noise.

Large-Scale Participation

Your solution should be designed to scale to large audiences. This includes robust connection management and simulcast options to accommodate each user's network capacity.

In-Meeting Chat

A built-in chat allows attendees to send text messages during the session. It should support modern features such as file upload, emojis, reactions, and editing to facilitate side conversations without interrupting the meeting.

Screen Sharing

Participants should be able to share their screen with others. A proper implementation captures the screen contents with a clear display and minimal latency, making text and images easily viewable.

Session Recording and Transcription

Many platforms let users record meetings. This allows attendees to review what was said or share the meeting later, accommodating employees or students who could not attend.

Conferencing solutions often include accessibility options for AI-based transcription or live captions. 

Participant Collaboration Tools

A rich set of in-app collaboration tools helps keep meetings interactive and engaging for all participants. Some of the top tools include:

Whiteboard and Live Annotations

Virtual whiteboards that enable users to draw in real-time are an essential feature for teaching and business use cases. You can supplement this by allowing annotation on shared screens or slides.

Breakout Rooms and Session Timers

Breakout rooms allow hosts to temporarily split large meetings into smaller groups to facilitate more direct interaction. For example, a meeting with 100 people could be split into 20 rooms of five people each for a cross-departmental brainstorming session.

Some platforms have countdown timers for breakout rooms to bring participants back to the main meeting after the set time has elapsed.

Host and Moderator Controls

Effective conferencing solutions provide robust controls to help hosts manage participants and the overall meeting flow. These controls include:

Participant Moderation

Hosts can manage meetings by muting or unmuting participants, spotlighting speakers, granting speaking permissions, and removing disruptive users.

Waiting Rooms

Hosts may screen participants before admitting them to a meeting by setting up a waiting room. Additionally, they can password-protect meetings to prevent uninvited access.

Web Conferencing Software

Web conferencing relies on dedicated software to deliver real-time communication. This software can be:

Standalone platforms: Tools like Zoom, Microsoft Teams, or Google Meet provide out-of-the-box conferencing functionality for businesses and individuals.

Integrated software solutions: Companies embed conferencing features directly into their products through APIs and SDKs. For example, edtech platforms integrate web conferencing software so teachers and students don't have to switch to a third-party tool.

On-premise vs. cloud-based: Most conferencing software today is cloud-hosted for scalability and ease of access, but some industries (like healthcare or finance) may deploy on-premise software for stricter compliance and data control.

Open-source options: Projects like Jitsi Meet or BigBlueButton offer customizable conferencing software that developers can self-host and adapt.

Common Use Cases

Below are some of the top use cases:

Edtech

For online education, web conferencing enables virtual classrooms and instructor-led training, connecting teachers, students, and administrators in real time.

It caters to diverse learning styles through visual aids and recorded sessions, which improve accessibility. Other features, such as breakout rooms and digital whiteboards, make lessons more interactive. Students can engage in group discussions, collaborate on assignments, and provide peer-to-peer support. Teachers can also deliver support through conferencing to address individual learning needs.

Telehealth

Embedding web conferencing into healthcare applications can transform interactions, reduce communication barriers, and maintain compliance. It helps handle virtual visits, remote patient monitoring, and medical education.

Patients in isolated communities can interact with healthcare professionals without making hospital trips for consultations or checkups. Providers can also participate in community engagements through virtual conferences and events to create awareness of medical conditions.

It's also well-suited for mental healthcare. For example, It's Complicated, a therapy community platform, integrated in-app video sessions to reliably and securely connect therapists and patients.

Team Collaboration and Management

Field operations teams often use these tools and take advantage of all of their associated features to run brainstorms, co-edit documents, review designs, and conduct interviews. Integrations with calendars, docs, task trackers, and CRMs centralize these workflows in one place, further enhancing collaboration.

Virtual Events and Webinars 

Web conferencing infrastructure powers large events and webinars.

With its scalable architecture, companies can host marketing webinars for lead generation, while industry leaders can hold panel discussions. Virtual event platforms gather a global audience without the costs of physical events.

Multi-stream support, on-demand recording, and analytic tools help organizers maximize reach and engagement.

Dating Apps

Integrating conferencing functionality into dating apps gives users a safe way to connect before meeting in person. Features such as in-platform video calling, fun icebreaker games, and custom layouts can provide a more engaging experience.

Frequently Asked Questions