ZyXEL Communications ADSL2+4 User Manual

 Chapter 20 Diagnostic

P-660H-T1v3s User’s Guide

The following table describes the fields in this screen.  

Table 60   Maintenance > Diagnostic > DSL Line

ATM Status

Click this to view your DSL connection’s Asynchronous Transfer Mode 
(ATM) statistics. ATM is a networking technology that provides high-
speed data transfer. ATM uses fixed-size packets of information called 
cells. With ATM, a high QoS (Quality of Service) can be guaranteed. 

The (Segmentation and Reassembly) SAR driver translates packets into 
ATM cells. It also receives ATM cells and reassembles them into packets.

These counters are set back to zero whenever the device starts up.

inPkts is the number of good ATM cells that have been received.

inDiscards is the number of received ATM cells that were rejected.

outPkts is the number of ATM cells that have been sent.

outDiscards is the number of ATM cells sent that were rejected.

inF4Pkts is the number of ATM Operations, Administration, and 
Management (OAM) F4 cells that have been received. See ITU 
recommendation I.610 for more on OAM for ATM.

outF4Pkts is the number of ATM OAM F4 cells that have been sent. 

inF5Pkts is the number of ATM OAM F5 cells that have been received.

outF5Pkts is the number of ATM OAM F5 cells that have been sent.

openChan is the number of times that the P-660H-T1v3s has opened a 
logical DSL channel.

closeChan is the number of times that the P-660H-T1v3s has closed a 
logical DSL channel.

txRate is the number of bytes transmitted per second.

rxRate is the number of bytes received per second.

ATM Loopback 
Test

Click this to start the ATM loopback test. Make sure you have configured 
at least one PVC with proper VPIs/VCIs before you begin this test. The P-
660H-T1v3s sends an OAM F5 packet to the DSLAM/ATM switch and then 
returns it (loops it back) to the P-660H-T1v3s. The ATM loopback test is 
useful for troubleshooting problems with the DSLAM and ATM network.