Net Optics iBypass HD - Manual (Page 10)

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iBypass HD
Traffic Statistics
The iBypass HD collects statistics about the traffic passing through each of its ports. The statistics can be viewed and
cleared through the management interface.
The traffic statistics collected by the bypass switch on each of its ports are:
• Peak traffic rate
• Time of the peak traffic
• Current bandwidth utilization
• Total number of packets
• Total number of bytes
• Number of Cyclical Redundancy Check (CRC) errors
• Number of oversize packets
Note __________________________________________________________________________________________________
The traffic statistics counters are 32 bits wide, so the maximum value of each counter is 4,294,967,295. The counters
roll over to 0 after the maximum count is reached. Be aware that, at 1 Gbps, the Total Bytes counter can roll over in as
short a time as 0.34 seconds and the Total Packets counter in 22 seconds.
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CRC Forwarding
The iBypass HD forwards all packets to the monitor ports, even packets that have CRC errors.
Jumbo Packets
The iBypass HD can be set to accept or reject jumbo packets, which are packets longer than the Ethernet standard
maximum length of 1,518 bytes. The maximum packet size passed to the monitor ports by the iBypass HD can be set
from 64 to 12,000 bytes.
Link Fault Detect
The iBypass HD supports the Net Optics Link Fault Detect (LFD) feature on the in-line network ports. When LFD is on,
if one port of an in-line pair loses link, the other port is forced to drop the link as well. This feature ensures that switches
and routers on both sides of the link see the failure so they can take remedial action such as rerouting traffic around the
failed link. This feature can be turned on or off through the management interface.
Note: __________________________________________________________________________________________________
When a port is set for autonegotiation and LFD is on, autonegotiation can take as long as 10 seconds. During this
period, the link speed can change and the Link LED might go on and off several times.
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Bypass Detect
The Bypass Detect feature enables an IPS to be alerted when the bypass switch is in Bypass On mode. When Bypass
Detect is enabled and the switch is in Bypass On mode, monitor ports 1 and 2 are cycled off for 5 seconds followed by
on for 15 seconds. The loss of link signals the IPS that the switch has entered Bypass On mode, while the 15 seconds of
on time enable the switch to test the state of the IPS by issuing Heartbeat packets.