When EFT8 is used on the OptiX OSN1500B subrack, the EFT8 veneer is an Ethernet transparent transmission veneer, which is mainly used to solve the telecommunication application areas such as Ethernet service access, bandwidth management and Ethernet service aggregation. It supports 1518Byte～1535Byte message length setting, and Jumbo frames not larger than 6144Byte are supported on ports 1～4 and 9～12, and Jumbo frames not larger than 9600Byte are supported on ports 5～8 and 13～16. Ports 5-8, 13-16 support Jumbo frames not larger than 9600 Byte. 1518 Byte to 9600 Byte message length settings are supported, and Jumbo frames not larger than 9600 Byte are supported.The available slots for the EFT8 are related to whether or not the EFT8 is equipped with an interface board. When EFT8 does not have an interface board, the EFT8 board can be inserted in slots 11 to 13 (bandwidth 622 Mbit/s) of the subrack. When the EFT8 is equipped with an interface board, the EFT8 veneer can be inserted in slots 12 to 13 of the subrack (bandwidth 1.25Gbit/s). Indicators on the panel of the single board are: single board hardware status light (STAT) - red and green dual-color indicator, service activation status light (ACT) green indicator single board software status light, (PROG) - red and green dual-color indicator service alarm indicator, (SRV) - red, green, yellow three colors Indicator Connection Status Indicator, (LINK)-Green Indicator, located on the RJ-45 connector Data Transmission and Receipt Indicator, (ACT)-Orange Indicator, located on the RJ-45 connector The N1EFT8 single-board has and only has one keyswitch on the snap-in panel, and this keyswitch is the reset switch. Do not press this key when the single board is in normal operation, or it will cause a hard reset of the single board, which may result in loss of service.

Problem Description

The OSN1500 device has newly expanded a SSN2EFT8 board to interface with the ZTE Ethernet board to open a major customer circuit of the Agricultural Bank of China. After adding the single board network management and configuring the service, it was found that it was not possible to dock with ZTE, and the OSN1500 EFT8 single board and the ZTE Ethernet board directly hanged the portable machine for ping test, and the result was that it was still not possible to ping.

Processing

After troubleshooting, it was found that:

1, the business configuration is correct, docking the two ends of the time slot according to the 3-7-3 model is not wrong

2, port mode are 100M full duplex

3, ZTE check their Ethernet data configuration is correct.

There are no alarms on the network management, and the business configuration is fine, but the ping is not available. At this time, I noticed that the EFT8 normally used in the previous network is SSN1EFT8, and the new expansion is SSN2EFT8, but there is no difference. Doubt N2 single board has any restrictions, through the collection of data sent to the R & D analysis, found that the packet is in the single board decapsulation module is discarded, so the focus of suspicion of this module has a problem, will be the module to collect all the registers out of the comparison, found that the N1 and N2 single board the following register differences, and ultimately proved that docking can not be the reason is that the N2 single board GTP checksum is too strict.

Failure causes

After checking, it is found that this OSN 1500 device has an EFT8 single board in use before, and it is interoperable with the ZTE device. For the new expansion of this EFT8 single board, the following reasons are analyzed:

1, whether there is a problem with the service configuration, because there are different interspersed modes and sequential modes in the time slot docking.

2. Whether the Ethernet port negotiation mode is consistent

3, EFT8 board is a pure pass-through Ethernet board, whether ZTE's Ethernet board is correctly configured with VLANs.

Recommendations and Summary

Solution

1. Modify the encapsulation mode of docking to LAPS

2. ZTE modifies the sent GFP type to 0x1001, and the HEC check value of the Type field to 0x1352.

3、Apply SSN1EFT8 to the customer to replace the SSN2EFT8 that cannot be docked, and the R&D informs that the single board software will be modified subsequently to modify the checksum of N2 single board for GFP to be the same as that of N1.