beautypg.com

2 e-series ethernet utilization window – Cisco ONS 15454 SDH User Manual

Page 15

background image

15-15

Cisco ONS 15454 SDH Reference Manual, R4.6

April 2008

Chapter 15 Performance Monitoring

15.5.1 E-Series Ethernet Card Performance Monitoring Parameters

15.5.1.2 E-Series Ethernet Utilization Window

The Utilization window shows the percentage of transmit (Tx) and receive (Rx) line bandwidth used by
the Ethernet ports during consecutive time segments. The Mode field displays the real-time mode status,
such as 100 Full, which is the mode setting configured on the E-Series port. However, if the E-Series
port is set to autonegotiate the mode (Auto), this field shows the result of the link negotiation between
the E-Series and the peer Ethernet device attached directly to the E-Series port.

The Utilization window provides an Interval menu that enables you to set time intervals of 1 minute,
15 minutes, 1 hour, and 1 day. Line utilization is calculated with the following formulas:

Rx = (inOctets + inPkts * 20) * 8 / 100% interval * maxBaseRate

Tx = (outOctets + outPkts * 20) * 8 / 100% interval * maxBaseRate

The interval is defined in seconds. The maxBaseRate is defined by raw bits per second in one direction
for the Ethernet port (that is, 1 Gbps). STS circuit maxBaseRates are shown in

Table 15-16

.

Rx FCS

Number of packets with a Frame Check Sequence (FCS)
error. FCS errors indicate frame corruption during
transmission.

Rx Alignment

Number of packets with alignment errors (received
incomplete frames).

Rx Runts

Measures undersized packets with bad cyclic redundancy
check (CRC) errors.

Rx Shorts

Measures undersized packets with good cyclic redundancy
check (CRC) errors.

Rx Oversized + Jabbers

Measures oversized packets and jabbers. Size is greater than
1522 errors regardless of cyclic redundancy check (CRC)
errors.

Rx Giants

Number of packets received that are greater than 1518 bytes
in length for untagged interfaces and 1522 bytes for tagged
interfaces.

Tx Collisions

Number of transmit packets that are collisions; the port and
the attached device transmitting at the same time caused
collisions.

Tx Late Collisions

Number of frames that were not transmitted since they
encountered a collision outside of the normal collision
window. Normally, late collision events should occur only
rarely, if at all.

Tx Excessive Collisions

Number of consecutive collisions.

Tx Deferred

Number of packets deferred.

Table 15-15 E-Series Ethernet Statistics Parameters (continued)

Parameter

Meaning