2G/3G Co-LAC

[Lazaros]

Hi all,

There could be a drawback with common LAC, due to the fact that due to different paging capacity, there could be a great decrease of the LAC area, if you move from different LAC to common LAC. Eg a city of 4mil people may have in 2G 8 LAC and in 3G 3 LAC. When moving to common LAC, there might be totally 10 LACs, which significantly increases the LAU in 3G network (moving from 3 LAC to 10 LAC). I only see this problem with common LAC

[srilasitha]

Hi

Huawei highlighted following impacts in Co-LAC for 2G & 3G.


The 2G/3G Shared LAC feature has the following impacts on the system:
• When a subscriber roams between the BSC and the RNC in the same location area, location update may not be initiated. Consequently, the current access network type of the subscriber stored in the VLR may be incorrect.
• If the called party is located in the shared LAC, the called party cannot reject the VP call when the MSRN is being allocated.
• The current access network type in the PSI response may be incorrect.
• The paging request is sent over the A interface and the Iu interface at the same time. Consequently, the paging traffic increases.
• The 2G performance measurement which uses the location area as the measurement object cannot be distinguished from the 3G performance measurement.

Does anyone know the impact severity for the following issue and the remedial action.

• If the called party is located in the shared LAC, the called party cannot reject the VP call when the MSRN is being allocated.