When joining a session, the first screen visible is a test screen called the Landing Page. From the Landing Page, you are connected to a Media Server. This activates a "muted" continuously-generated audio track that is sent to the media server.
Once a connection is established, Jigsaw Interactive begins collecting WebRTC statistics. Statistics are checked every 10 seconds, where the statistics are analyzed and the message on the Landing Page is updated if any issues are detected.
What is Checked on the Landing Page?
- Blocking of Incoming or Outgoing Traffic to Jigsaw
- Permission from Browser to Generate Audio Track
- Network Too Slow or Limited in Bandwidth
- Network Blocking Outbound or Inbound "UDP Traffic"
- Lost Packets
- Jitter Consistency
- No Introduction of Extra Packets
Blocking of Incoming or Outgoing Traffic to Jigsaw
If the User's network/computer is blocking either incoming or outgoing traffic to Jigsaw, the User's Network/Computer's traffic will be rerouted through Jigsaw's TURN server. This test is checking to see if the user's network/computer is blocking either incoming or outgoing traffic to Jigsaw. This is usually caused by a Firewall. If traffic is being blocked, Jigsaw routes the traffic through an external TURN server which finds a way to route the traffic in and out of the user's network. If the TURN server is used, a message is displayed on the Landing Page: "You are using TURN server and you might have issues with the audio/video communication.". The user is informed of re-routing to the TURN server because it introduces slowness into the connection between the user and Jigsaw because all traffic going to and coming from the user must be directed through the TURN server and then on to its destination. This takes more time and can cause delays in audio/video streams in Jigsaw.
If the computer/network is blocking Jigsaw's traffic, and re-routing to the TURN server is not possible because that is blocked also, the user will see the message: "Cannot send/receive audio or video.".
Permission from Browser to Generate Audio Track
There are times the user's browser will simply not allow the audio track to be generated for testing of the connection to occur (for example: Safari on the iPad). In this case, Jigsaw relies on the User to manually test the Camera and Microphone using the buttons on the Landing Page. The user will see the message: "Please use Test Camera/Microphone buttons to test your connectivity.".
Network Too Slow or Limited in Bandwidth
There are rare cases where the user's network is so slow due to high ping/latency or is limited in bandwidth that only the most basic "signaling" can get through. This means that no audio or video streams can be sent or received. If this occurs, the user will see the message: "Bad network. Cannot send/receive audio or video.".
Network Blocking Outbound or Inbound "UDP Traffic"
There are times when the user's network/computer is setup to block outbound or inbound "UDP traffic". We use the UDP protocol to send and receive audio and video streams. In these cases, the user will see the message: "Your network is blocking the UDP traffic and you might have issues with the audio/video communication.".
If all the above testing are successful, the next test is to check for "Lost Packets". All Internet traffic is sent in what is called "packets", which is just a chunk of data, wrapped in a header/footer, then sent as a "packet" across the Internet. The receiver of the packet must acknowledge that each packet has been received. If the acknowledgement does not happen for a packet, that packet is considered "lost". In those cases, the receiver must hold all subsequent packets in a queue and the lost packet must be sent again until successful, then the queued packets will be processed. Losing packets, or having to resend them, causes overall slowness in the sending of data, audio, and video. In this test, Jigsaw ensures the lost packets are less than 1% of the total packets. If 1% or more of packets are lost, the user will see the message: "You are having network issues!".
Packet Loss can be caused by many things such as a misconfiguration of the network, a bad network connection (bad wiring, bad network adapters, etc.), unwanted traffic (other network devices or other computers filling the network with traffic from backups, streaming from sites such as Netflix, gaming, etc.), outdated network devices (modems, routers, etc.), spyware/malware or other malicious software on any computer on the same network, overloaded computer/device which cannot keep up with the process load, etc.
While checking for lost packets, Jigsaw will also be tracking "Jitter". Jitter is what we call the variation in "ping" speeds. Ping speed is simply the length of time it takes a packet to get from the sender to the receiver then for the acknowledgement to get back to the sender. It is considered a problem if some pings are fast and some are slow. If the speed is not consistent, this points to a problem with the user's network (or their available bandwidth is inconsistent). This Jitter will likely have an effect on the quality of the audio and/or video that is sent and received in Jigsaw.
Jigsaw checks to see if the Jitter is less than 30 milliseconds (ms), recalculating every 10 seconds. If it averages more than 30 ms, the user will see the message: "You are having network issues!". If this occurs, the user should be able to see and hear the audio and video, but it could be choppy and unstable. Jitter and Packet Loss are typically related and share the same causes.
No Introduction of Extra Packets
Jigsaw also checks to ensure "extra packets" are not introduced into the stream over the 10-second period. This should only happen if the audio track is stopped or restarted for some reason or something unexpected were to occur. If this does happen, the user will see the message: "Please use Test Camera/Microphone buttons to test your connectivity.". If these manual tests pass, the user experience should be okay.
Attendees List Symbols and Browser Information
These are new features of Jigsaw.
The yellow triangle with the exclamation point symbol means that some networking problem was reported to that user on the Landing Page. Jigsaw carries that information into the session to show that this Attendee could experience problems due to network issues. Please note that this isn’t the feature where Jigsaw turns the attendee's name “orange”, instead this symbol is related with the specific tests that are performed on the Landing page (details in the What is Checked on the Landing Page section of this article).
Another new and helpful support feature is the O/S and Browser information that is shown directly within the session. This will allow the Attendee (and the Host/Presenters) to see this information as well by clicking the individual's name in the Attendees List to view the Browser and OS information shown under the Avatar image. This information can provide the user and/or Host/Presenters valuable information if the user is having problems with audio/video, screen sharing, etc. If the browser or OS is out-of-date, this can cause a less than fun experience in Jigsaw.