HP xw4400 Workstation - Manual (Page 114)

HP Remote Graphics 4.2.0 User's Guide
106
Using Timeouts
Various network conditions as well as end-user needs require the ability to specify
network warning, error and dialog timeouts. RGS enables relatively fine-grained
control over the network and dialog timeout values as well as an innovative form of
user notification when a warning timeout expires. This allows tuning for specific
network conditions and environments, such as low-bandwidth or high-latency
conditions. At the same time the user is notified of potential issues involving more
catastrophic or transient network conditions. This section describes the purpose,
type, function, and recommended settings for RGS timeouts.
The RGS Receiver and Sender have command-line options and properties that can
specify the network warning and error timeouts. The RGS Receiver also enables
timeout values available from the Receiver Control Panel.
There are several types or classifications of timeouts in the RGS product:
• Network Warning Timeouts: The Receiver uses network warning timeouts to
display a warning or notification of potential network connectivity loss if the
timeout expires.
• Network Error Timeouts: The Receiver and Sender use network error timeouts
to control the following:
o The maximum time that a Sender and Receiver will wait for or retry a
network invocation before reporting a network error and fully closing
the connection.
o The maximum time that a Receiver and Sender will wait for a sync-
pulse prior to fully closing the connection.
• Dialog Timeouts: The maximum time that a Receiver and Sender will display
a message/response dialog or wait for an invocation response between the
pair.
RGS uses TCP/IP over a standard computer network to transmit data. TCP/IP is a
reliable transport mechanism, but it still offers no guarantees on network packet
delivery. This is in contrast to the reliable connection that a keyboard, mouse, and
monitor enjoy when using a PS/2, USB, or video cable on a computer. (A complete
discussion of TCP/IP is beyond the scope of this document. Interested readers should
refer to any number of excellent references on this subject to fully cover this
material.)
The TCP/IP network stack typically performs well on a relatively stable network.
However, issues outside of RGS can affect the probability and timing of network
packet delivery that ultimately impact system performance. Issues such as
• network over-subscription results in congestion and packet loss
• CPU utilization from other processes/tasks starves the network stack
• send and receive response time fails due to inadequate bandwidth
• network switches, routers, and NICs can fail or be incorrectly configured