Manage and Monitor Meeting Bandwidth

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1 Page 1 of 5 Printed From: Close this Window Home > Learning Center > Tutorials > Manage and Monitor Meeting Bandwidth Manage and Monitor Meeting Bandwidth David Yun, Adobe Systems MARCH 2009 Expertise Level: Intermediate Screen sharing is one of the core tenets of web conferencing, yet to the vast majority of users, knowing how to screen share with confidence remains a mystery. How many times have you been in a meeting and heard a presenter ask, Can you see my screen? Likewise, how many of you can attest to wondering if everyone can truly hear you when when using Voice-over-IP? Latency and fidelity are the two areas where presenters most often come across challenges when performing higher bandwidth activities such as screen sharing, VoIP, broadcasting live video and playing back pre-recorded video and Flash Applications. Latency, by definition, refers to the amount of time it takes for information to travel from your computer to each attendees computer. Sometimes when users share their screen or broadcast VoIP, other meeting attendees can experience a high degree of latency, or a situation where a noticeable time lag occurs between when the presenter performs an action on their desktop or says a word and when that action is seen or heard by meeting attendees. Fidelity, on the other hand, is the accuracy with which an image is reproduced from the presenters screen or in the case of audio, how pristine the audio sounds. When hosting a meeting, it is your responsibility to properly manage a balance between latency and fidelity to ensure a great meeting experience for your attendees.whether you are using Voice-over-IP, broadcasting webcam video, or sharing your screen, you need to be very aware of the amount of data you are pushing over to your audience. Not doing this can quickly result in dropped audio, choppy video, or screensharing that is lagging far behind. Luckily, Connect Pro has a few tools to help you in this task. Optmize Room Bandwidth Settings Connect Pro has two room settings available for meeting attendees to optimize meeting performance. One is a global setting set by the meeting host and the other is a per-user setting that each participant can set individually. Fig 1. Correctly setting the room bandwidth is an essential step to enabling a great meeting experience for your attendees.

2 Page 2 of 5 First, meeting hosts can control the overall room bandwidth setting. Using this setting in conjunction with the latency information displayed in the participant list allows you to push the highest-quality screen fidelity to your audience. To change overall room bandwidth, select Meeting > Optimize Room Bandwidth. In this menu are three settings available for the most common bandwidth scenarios: Modem, DSL/Cable, and LAN. If a meeting host chooses LAN over DSL/Cable or Modem, the fidelity of the screen image or audio stream will be better, but with more bandwidth required and a higher chance of users on slower connections experiencing a higher degree of latency. Therefore, it is important to know your audiences connection speed. A general rule of thumb is if you are meeting with a purely internal audience who are all connected locally on a T3 LAN, you likely want to maximize your fidelity since bandwidth is not much of a concern. If you are meeting with a highly diverse external audience who are attending the meeting on a variety of connections, its probably a good idea to lower the room bandwidth settings to DSL or Modem to ensure that users do not experience latency. Similarly, meeting attendees can set their personal bandwidth setting through the Meeting menu. This setting is applied to a particular attendees experience. If an attendee sets their bandwidth setting to DSL/Cable and the meeting room bandwidth is set to LAN, the information sent to the attendees computer is tailored to their specified connection speed. If you are running a meeting with an attendee who is experiencing latency issues, instruct them to change this setting. Fig 2. Meeting participants can change their own connection speed. Monitoring Attendee Status It can be difficult, if not impossible to having non-technical participants who are unfamiliar with the software manage their own connection speed. Luckly, Connect Pro also has a little known feature called Attendee Connection Status that allows meeting hosts monitor the available bandwidth of meeting attendees. Depending on who your audience is, you may want to either lower room bandwidth before the meeting starts, as outlined in above, or use that technique as a backup if attendees are experiencing latency issues. If you run your meeting using the LAN setting, it is important that you monitor attendee connection status to ensure that all attendees are having a good viewing experience. Fig 3. Show Connection Status is turned off by default. When selected, meeting hosts are shown indicators of attendees connection speeds

3 Page 3 of 5 Each of these indicators represents various connection states for meeting participants. If Show Connection Status is selected and you do not see any indicators, no users are experiencing latency issues. Generally, if the yellow icon is displayed, there is a moderate chance that this attendee will experience latency issues, especially during bandwidth-intensive moments in the meeting. If the red icon is displayed, this attendee is most likely experiencing latency issues. If this is happening, try to minimize high bandwidth actions by either pausing or stopping actions such as screen sharing, video and voice all together until attendees have a chance to catch up. Icon Displays When... The attendee manually selected Modem as their connection speed and the room bandwidth is set to LAN. The user is experiencing latency higher than 4 seconds. The meeting has dropped 20% or more of the data for this user because that user was falling behind. None of the preceding items that would cause the red indicator to appear applies. The user selected DSL as their connection speed and the room bandwidth is set to LAN. The user selected Modem as their connection speed and the room bandwidth is set to DSL. The user is experiencing a latency higher than 0.5 seconds. The meeting has been dropping between 5% to 20% of the data for this user because that user was falling behind. Additionally, a tooltip appears when you mouse over a connection status icon for an attendee. This tooltip gives you details about the issues that the user is experiencing. Fig 4. Connetion Status Tooltips provide clues into precisely what problems an attendee is encountering. Tooltip Displays when... Connection: Modem The attendees personal meeting room connection speed is set to Modem and the room bandwidth speed is set to DSL or LAN. Connection: DSL The attendees personal meeting room connection speed is set to DSL and the room bandwidth speed is set to LAN. Latency: High The attendee is experiencing latency of greater than 4 seconds. Latency: Medium The attendee is experiencing latency of greater than 0.5 seconds, but less than 4 seconds.

4 Page 4 of 5 Drops: >20% The attendees meeting instance is losing more than 20% of the data to keep the user from falling too far behind Drops: 5%-20% The attendees meeting instance is losing more than 5% of the data but not more than 20% to keep the user from falling too far behind. An Advanced Scenario: Bandwidth Distribution with Screen sharing, VoIP and live video In this section, I discuss how bandwidth is considered when multiple bandwidth-intensive features such as screen sharing, voice over IP (VoIP), and live webcam video are being used simultaneously. If you wont be sharing live video or using VoIP, you may want to skip this section, as it can get complicated. However, if you are an advanced user of the system who wants to squeeze the last bit of performance out of Connect Pro, this section will help you achieve that. When a meeting host is using screen sharing along with VoIP and live video with the Camera and Voice pod, a lot of information needs to be transmitted from computer to computer. To account for this, Connect Pro has a sophisticated scheme for handling scenarios where individual meeting participants have constrained bandwidth, and to decide how to keep users from falling too far behind while still having a good meeting experience. Connect Pro broadcasts simple meeting events like slide changes and chat first, then voice, then screen sharing, then live video. To describe how this works in a real-world scenario, lets say a meeting is being conducted with video (at 50 Kbps), voice (at 22 Kbps) and screen sharing. A host and two participants are in the meeting. Here is how Connect Pro prioritizes the various streams to ensure an optimal experience. Lisa is hosting the meeting on a corporate LAN that supports a 10 Mbps connection, so Connect Pro has a lot of bandwidth to play with. Even if Lisa is sharing her screen at a 1600x1200 pixel resolution and showing a slide show of colorful snapshots from the company party, there is plenty of bandwidth to broadcast her screen with little or no effect to her video and audio streams. If all users in the meeting are on this type of connection, Connect Pro does have a feature called Turbo Screensharing for extreme screen sharing that is turned off by default. However, be forewarned that this feature is intended only for those customers with highly performant networks. This setting would do a good job of filling that 10 mbps connection to capacity with beautiful, high-fidelity renditions of Lisas Christmas pictures. Dawn is a meeting participant attending from home on a 500 Kbps DSL connection. In this scenario, 22 Kbps are used for voice and 50 Kbps are used for video, leaving 428 Kbps for screen sharing. If the changes on Lisas screen are small, or if the screen is displaying mostly text, the screen-sharing experience is flawless. But if Lisa suddenly presents a fullscreen picture of the Christmas party that represents 3000 Kbps of information, Connect Pro freezes the live video stream, leaves the audio stream alone, and uses 478 Kbps for several seconds to re-render Dawns view of Lisas screen. After the screen is redrawn, Connect Pro unfreezes the live video stream back to its normal state. Because screen sharing is almost always more important than live video, Connect Pro always takes bandwidth from live video in favor of screen sharing to optimize the experience. Marty is participating in a meeting from his home with a 48 Kbps modem. If 22 Kbps are used for the voice, that leaves only 26 Kbps for video and screen sharing (Connect Pro does require some bandwidth to keep the basic meeting running, but it is negligible enough to ignore for this example). When an event happens that must be rendered by Martys computer, such as Lisa moving a picture around on the screen, Connect Pro automatically freezes Lisas live video stream in Martys view until the screen sharing catches up to Lisas computer. When the updated screen-sharing image is finished rendering, Connect Pro compresses the live video stream and ignores frames to squeeze the 50 kbps live video stream into the remaining 26 Kbps. Because voice is typically most critical for a smooth meeting experience, Connect Pro preserves the fidelity of the audio stream and reduces screen sharing and video fidelity to keep the audio smooth. Summary I cannot emphasize how important setting the correct room bandwidth and monitoring your attendees using Connection Status are to ensuring your meeting is running smoothly. Using thes two features in concert will enable you to maximize meeting fidelity while minimizing latency. Hopefully in this tutorial, you've learned some new techniques for how to better manage meeting bandwidth in a way that is intuitive and a pleasure to use. As the meeting host, you are the only one who has the power to use

5 Page 5 of 5 these tools and in turn, provide a great experience for your attendees so they can focus on what really matters, the content and discussion in the meeting itself. Terms of use Online privacy policy About this site Contact Us Send feedback Copyright 2009 Adobe Systems Incorporated. All rights reserved.