Duplicate Keystrokes in Spider KVM Session and Key Release Timeout Setting
- Jane
Why is my Spider session duplicating keystrokes? What can I do to keep this from happening?
Duplicate keystrokes are typically accompanied by slow internet browsing or slow connections to other hosts at the Spider's location. This is caused by excessive network latency which can result in duplicated keystrokes in Spider KVM sessions.
One way to quickly determine the network 'health' between two IP endpoints is to perform a continuous ping from one endpoint to the other, e.g., The KVM client PC and the Spider.
Run a continuous ping (command: C:\>ping -t ip_address) for 1 to 2 minutes and break it with a ^C (ctrl+C).
The resulting ping stats will give you an idea of the quality of network connection between the endpoints; how busy it is, and how fast (or slow) the connection is between them. Pay attention to the amount of latency (in milliseconds) or dropped packets in the resulting stats.
Less latency usually denotes a faster or less busy network.
The following numbers are a rough approximation of the kind of latency times to expect from given network scenarios and conditions:
| Latency | Type of network |
| 1ms - 5ms | LAN speeds |
| 5ms - 20ms | busy LAN speeds |
| 10ms - 50ms | typical broadband internet connection (cable, DSL, Fiber) |
| 50ms - 100ms | high traffic internet connection, typical POTS (dial-up) internet connection |
| >100ms | high latency internet connections, satellite connections |
Obviously, the less latency there is on your network, the better. Dropped packets are even more detrimental to the connection. The TCP hosts have to re-send the packets to get correct communication to each other slowing down the connection further.
The Spider has a 'Key Release Timeout' setting that allows the KVM connection to 'compensate' and tolerate network latency conditions to inhibit the doubling of keystrokes.
To enable this feature
- log into the Spider WebManager
- click on the 'Interfaces' tab
- click on the Keyboard/Mouse link
- check the box for 'Key Release Timeout' enabled.
- select one of four timeout settings: 25ms, 50ms, 100ms, 200ms to match the ambient latency on the network.
Select a value that is low enough to remove the duplicated keystrokes without adding any more delay to the KVM session.
Ultimately, the Key Release Timeout feature Spider can compensate for only so much network lag, and no more. Persistent keystroke doubling will have to be resolved at the network level.
[Originally Published On: 07/20/2009 05:00 PM]