Filter
Top Products
5-6
Cisco MGX 8240 Hardware User’s Guide
Release 3.0, Part Number 78-10728-01, July 2000
Chapter 5 Statistics
Statistics
Some conditions exist when the frame is not passed through. The ATM Forum CES specification states
that the CES IWF sends cells containing all ones (an unframed AIS signal) when Loss of Signal (LOS)
is detected for the DS1. Since the MGX 8240 does not physically terminate the DS1s, LOS cannot be
detected. If an auxiliary M13 multiplexer is used to terminate the DS1, it detects the LOS and generates
an AIS signal within the DS1 toward the MGX 8240, which passes it through in cells towards the far end.
Although the MGX 8240 cannot detect DS1 LOS, it can detect the following problems:
• Containing DS3 Loss of Signal (only for DS3 I/O)
• Containing DS3 Loss of Frame
• Containing DS3 Receiving AIS
• DS1 Out-of-Frame (only applies when set to monitor the DS1 frame)
When the MGX 8240 detects one of these problems, it sends cells containing all ones toward the far end.
Structured Service Interface Alarms
When providing structured DS1 CES service, the DS1 frame is terminated on the local CES service
interface. The ATM Forum CES specification states that when DS1 Loss of Signal, AIS, or Out-of-Frame
is detected, the CES IWF sends cells containing Trunk Conditioning. Since the MGX 8240 chassis does
not physically terminate the DS1s, LOS cannot be detected. If an auxiliary M13 multiplexer is used to
terminate the DS1, it detects the LOS and generates an AIS signal within the DS1, towards the
MGX 8240, which detects the AIS and reacts appropriately. Although the MGX 8240 cannot detect DS1
LOS, it can detect the following problems:
• DS1 Out-of-Frame
• DS1 Receiving AIS
• Containing DS3 Loss of Signal
• Containing DS3 Loss of Frame
• Containing DS3 Receiving AIS
When the MGX 8240 detects one of these problems, it sends cells containing Trunk Conditioning
towards the far end.
Statistics
Each of the ATM connection statistics below is kept for the current 15-minute interval, a history of the
last two 15-minute intervals (30 minutes), and the current 24-hour period (starting and ending at
midnight GMT).
• Valid Cells Ingress
• Cells Ingress discarded due to HEC Errors
• Cells Egress