Nokia GGSN connect all GPRS user whom are online.
Users are disconnected from service.
1. Request for information from mobile team about phenomenal.
2. GTP v1 and v0 use different IP address subnet and different UDP port.
3. To let only GTP v0 from SGSN reach GGSN can be done by 2 solutions.
a. Run only GTP v0 on SGSN but this cause some feature on SGSN will also be disabled.
b. Run GTP v0 and v1 on SGSN as normal but perform packet filtering on NE40 to deny all traffic from specific source address and UPD port not to reach GGSN. Then SGSN will down grade GTP version itself to v0 and this will not make GGSN see the change of version. Therefore, user will not be disconnected.
4. EACL are defined accordingly to source IP address and UDP port that GTP v1 use.
5. EACL are applied to all ports that connected to SGSN.
Siemens SGSN site CWT connect to GGSN site SCH via core network NE40 had problem when fail on negotiation with GGSN by using GRPS Tunneling Protocol (GTP) version 1 causing SGSN down grade GTP version itself to version 0 and try to negotiate version again with GGSN then GGSN see the change of GTP version in the established session make GGSN disconnect all GRPS user online at that moment
- After EACL are applied to ports that connect to NE40. GPRS service runs normally.
- This problem did not occur on NE40. Rather to be on Siemens SGSN and Nokia GGSN causing by different detail in GTP.