Enterasys Networks CSX6000 - Manual (Page 192)

USER’S GUIDE
192 CyberSWITCH
• IP Host (RFC 1294)
RFC 1294 provides a simple security exchange at connection time, along with an encapsulation
method for IP datagrams.
B ASE D ATA R ATE
Only used for Dial-Out. This value represents the throughput on a B-channel or pre-ISDN link
connecting the CyberSWITCH to a device. The data rate can be specified as either 56,000 or 64,000
bps. The default configuration for the base data rate is 64,000 bps. If 64,000-bps connections to the
device are not possible, this value should be set at 56,000 bps.
I NITIAL D ATA R ATE
Only used for Dial-Out. The initial data rate determines the bandwidth that will be attempted when
opening the first wide area connection. This provides you with a mechanism to request that a group
of parallel connections be made to a remote device rather than a single connection. This will allow
data to begin to flow at greater rates without waiting for the Throughput Monitor to detect an
overload condition. Calls will be made until an additional call would exceed the configured value.
The value is configured as a number from 2,400 to 1,024,000. For example, if you have configured
the Base Data Rate at 64 Kbps, and the Initial Data Rate at 256,000, the system would attempt to
initially use four calls (connections) running in parallel (256,000 / 64,000 = 4). The default
configuration for the Initial Data Rate is 64,000 bps.
M AXIMUM D ATA R ATE
The Maximum Data Rate is used to limit the total number of channels that can be committed to a
single device (logical connection). This sets an upper boundary for line and capacity utilization.
This upper boundary allows you to keep one remote device from crowding out other devices and
using an unfair share of available resources. This parameter is enforced on inbound and outbound
calls. The system will not accept or make a call when the added bandwidth will exceed the
configured maximum. The value is configured as a number from 2,400 bps to 3,072,000 bps. You
may configure any value in this range. For example, if you have configured the base data rate at
64,000 bps, and the maximum data rate at 512,000 bps, the system would use a maximum of eight
calls (connections) running in parallel to open up bandwidth (512,000 / 64,000 = 8). The value need
not be a multiple of the Base Data Rate. The default configuration for the maximum data rate is
128,000 bps.
Note: A condition may occur in which the number of connections has reached the point where
the maximum data rate will be exceeded with the next additional connection, and yet the
remote device may initiate another call to the system. This inbound call causes the
maximum data rate to be exceeded and the system will drop a connection. If the remote
device is auto-dialing, this flip-flop condition will continue until you manually correct the
problem. To correct this problem, configure the Throughput Monitor information to be
identical on the CyberSWITCH and the remote device, or disable Throughput Monitoring
on one of the devices. The Internet Engineering Task Force (IETF) is working on a standard
solution to this problem.
If you are using multiple connections running in parallel (i.e., to the same device), the
maximum number of connections that can be aggregated is 32. For maximum performance,
however, we recommend aggregating no more than eight connections at a time.