HP StorageWorks Enterprise File Services WAN Accelerator 3.0.4 deployment guide (AG421-96001, March 2007)

130 13 - TROUBLESHOOTING DEPLOYMENT PROBLEMS
Problem: Underutilized Fat Pipe
A fat pipe is a network that can carry large amounts of data without significantly
degrading transmission speed. If you have a fat pipe that is not being fully utilized and
you are experiencing WAN congestion, latency, and packet loss as a result of the
limitations of regular TCP, consider the solutions outlined in this section.
Solution:
Enable
High-Speed
Transmission
Control
Protocol
To better utilize fat pipes such as in Gigabit Ethernet (GigE) WANs, consider enabling
high-speed Transmission Control Protocol (HSTCP). HSTCP is a feature you can
enable on HP EFS WAN Accelerator 5000-series models to ease WAN congestion
caused by limitations with regular TCP that can result in packet loss. Enabling the
HSTCP feature enables more complete utilization of “long fat pipes” (high-bandwidth,
high-delay networks).
IMPORTANT: HP recommends that you only enable HSTCP after you have carefully
evaluated whether HSTCP will benefit your network environment. For a discussion of
the tradeoffs of enabling HSTCP, see the section “tcp highspeed enable” in the HP
StorageWorks Enterprise File Services WAN Accelerator Command-Line Interface
Reference Manual
To display HSTCP settings, use the CLI command show tcp highspeed. To configure
HSTCP, use the CLI command tcp highspeed enable.
For more information, see the HP StorageWorks Enterprise File Services WAN
Accelerator Command-Line Interface Reference Manual or the HP Enterprise File
Services WAN Accelerator Management Console User Guide.