Best practices
The quality of the audio and video during a VidyoConference is directly tied to the quality of the network at the endpoint. For details about the network operability specifications, refer to the “Network Readiness” section in this document, but in general, follow these simple guidelines:
Except when using VidyoMobile™, use a wired network connection whenever possible.Connect your audio and video devices (cameras, microphones, etc.) directly into one of your computer’s USB ports whenever possible rather than using a USB hub.Ensure that your audio and video devices have been updated with the latest drivers.If you’re using a laptop, avoid running on battery because that may reduce performance and video quality.
Network readiness
This section provides guidelines for ensuring that your network is ready for VidyoConferencing.
Client Ports
The ports listed in the following table are the default ports and are configurable (except for VidyoProxy 443 TCP and local 63457 TCP).
Port Description
80/443 TCP VidyoPortal™ (HTTP/HTTPS/SOAP)
17992 TCP VidyoManager signaling (EMCP) – to VidyoPortal
17990 TCP VidyoRouter™ signaling (SCIP/CMCP) – to VidyoRouters
50000-65535 UDP Media – to VidyoRouters (6 ports per call)
63457 TCP Local on client PC; client to/from browser
443 TCP VidyoProxy (VidyoRouters)**
** Not ideal; it is best to have direct access; VidyoProxy should be a fallback option only.
WebProxy:
If detected, may also raise a warning to the user because using WebProxy usually also means connecting only via VidyoProxy.
UDP Timeout:
Consider testing for this. UDP timeout at firewall/network router/etc. will drop a call at the timeout set (i.e., Cisco ASA default is 2 minutes).
Packet Loss
Packet Loss occurs when one or more packets are not received by the intended recipient as expected due to a congested network or failure in transmission. The following should be measured and presented for packet loss
Packet Loss Packet Loss Per Second
GREEN No Loss - < 1%
YELLOW > 1%
RED > 5%
Packet Latency
Latency is the measure of delay on the network, usually measured in milliseconds and for round trip time.
Packet Latency Description
IDEAL Less than 100ms
OK 100ms-250ms
WARNING 250-450ms
NO GOOD More than (>) 450ms
Note: VidyoProxy will not support latency greater than (>) 200ms.
Jitter
Jitter is a measure of the variability over time of packet latency across a network. A network with constant latency has no variation (or jitter). Packet jitter is expressed as an average of the deviation from the network mean latency. When jitter occurs during video/audio communication, the effect is lost audio, halted audio, or unnatural audio. It is highly desirable to eliminate or minimize such events during live video/audio communications. Monitoring the jitter provides an indication of the quality of the network.
Jitter Description
IDEAL No Jitter, latency is relatively consistent, less than (<) 10ms
WORKABLE Jitter less than 100ms
WARNING Jitter 101-200ms
NO GOOD Jitter more than (>) 200ms
Available Bandwidth
Available bandwidth is the amount of bandwidth available to the client. The client statistics show the maximum available bandwidth that the client may use, not the full amount available to the client host system. For Vidyo, the uplink bandwidth is straightforward. For downlink, it is very subjective, and depends on what is being viewed (that is, the number of participants, the window size, etc.).
Uplink:
Bandwidth Description
Best for HD Tx 1-1.2 MB Up/Send
Best for SD Tx 600-800 KB Up/Send
OK Tx 400-600 KB Up/Send
MED Tx 250-400 KB Up/Send
LOW Tx 150-250 KB Up/Send
NO GOOD Tx Less than 150 KB Up/Send – Audio Only
Note: Add 200 KB when data sharing
Downlink:
Bandwidth Description
IDEAL HD Rx 4 MB Down/Receive
IDEAL SD Rx 2-2.4 MB Down/Receive
OK Rx 400 KB -2 MB Down/Receive
MED Rx 250-400 KB Down/Receive
LOW Rx 150-250 KB Down/Receive
NO GOOD Rx Less than 150 KB Down/Receive – Audio Only
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