Hi everybody!
In this theme, I will finish explaining downstream network protection. At the end of these theme of downstream network protection, I will explain type B dual-homing protection and show commands for configuration.
Nowadays, customers want reliable services. They have little tolerance for service interruptions. Especially business users. Because of that, we must have protection in downstream, upstream protection and redundancy components in OLT.
GPON downstream networking protection has A, B, C and D modes. Current downstream networking protection is type B single/dual-homing protection and type C single/dual-homing protection.
Type B dual-homing protection is an expensive solution because it has 2 OLTs. This network protection has 2 OLTs (2 chassis, 2 slots, 2 service boards, 2 PON ports) and 2 backbone fibers. There is no protection in optical splitters and branch fibers.
Type B dual-homing protection has 2 different PON ports on the different boards and OLTs. One PON port is active and this is an active link. The second PON port is standby and this is the standby link. This protection can automatically switch from active to standby link when there is some problem with the active link.
Automatic switching can be triggered when one of the following conditions is met:
LOS occurs in the input direction,
the ONUs are offline,
the OLT (chassis, slot, service board, PON port) and ONU hardware is faulty, and
the OLT`s uplink is faulty.
Next figure show type B dual-homing protection:
When the active line is interrupted due to a backbone fiber or component (such as PON port, GPON board, slot, or chassis of OLT), the ONU will switch services to the standby line. If the OLT`s uplink is faulty, the system will automatic switch from active OLT to standby OLT, too.
When the primary line or uplink fix, the system will automatically start to switch services from standby to the primary line (active line). The OLT sends an automatic switchback message and the switchback time to the ONU.
Advantage: protection in 2 OLTs (2 chassis, 2 slots, 2 service boards and 2 PON ports) and 2 backbone fibers.
Disadvantage: expensive solution.
And the end, you can see the configuration on the active and standby OLT. TEST1 is the active OLT, TEST2 is the stanby OLT. Active and standby OLT PON ports are 0/2/1.
1. Configuration on the active OLT:
TEST1(config)#dual-parenting local-node ip-address x.x.x.x port xx key xxxx
TEST1(config)#dual-parenting peer-node standby ip-address x.x.x.x port xx key xxxx
TEST1(config)#dual-parenting sysnc enable
TEST1(config)#protect-group1 protect-target gpon-uni-port workmode dual-parenting
TEST1(protect-group-1)#protect-group member port 0/2/1 role work
TEST1(protect-group-1)#peer-group-member peer-node standby peer-port 0/2/1
TEST1(protect-group-1)#uplink-monitor port 0/8/0
TEST1(protect-group-1)#quit
2. Configuration on the standby OLT:
TEST2(config)#dual-parenting local-node ip-address x.x.x.x port xx key xxxx
TEST2(config)#dual-parenting peer-node active ip-address x.x.x.x port xx key xxxx
TEST2(config)#dual-parenting sysnc enable
TEST2(config)#protect-group1 protect-target gpon-uni-port workmode dual-parenting
TEST2(protect-group-1)#protect-group member port 0/2/1 role protect
TEST2(protect-group-1)#peer-group-member peer-node active peer-port 0/2/1
TEST2(protect-group-1)#protect-group enable
TEST2(protect-group-1)#uplink-monitor port 0/8/0
TEST2(protect-group-1)#quit
3. The command for display the protection group:
TEST(config)#display protect-group 1
4. Commands for delete protection group:
TEST(protect-group-1)#undo protect-group member port 0/2/1
TEST(protect-group-1)#undo peer-group-member
TEST(config)#undo protect-group 1
TEST(config)#dual-parenting sync disable
TEST(config)#undo dual-parenting local-node
TEST(config)#undo dual-parenting peer-node standby
Thank you!
