RADWIN2000UserManual Release2.8.30 15‐14
SystemOperationdescription
Figure15‐12:SecondaryLinkoperatingaftertheswitchbacktoPrimary
SystemOperationdescription
Normaloperation
•TDMservicesarecarriedbytheprimarylink
•Thesecondarylink(equipmentandairinterface)isoperatingbut
notcarryingusertraffic
•TDMportsonthesecondaryIDUsare tri‐state
Switchingto
backup
• Switchingtosecondarywi ll occurinthefollowingcases:
• Loss of the primary air interface due to sync-loss
• Loss of the primary air interface due to failure of the receiver to acquire expected
TDM data during a period of 24ms
• Primary equipment power off (either ODU or IDU, local or remote)
•Theswitchingresultwouldbe:
• TDM ports on the primary IDUs turn to tri-state
• TDM ports on the secondary IDUs become active
Backupoperation
•TDMservicesarecarriedbythesecondarylink
Switchingbackto
primary
• SwitchingbacktoprimarywilloccurassoonasthePrimarylinkis
fullyfunctionalfor1second