You can configure an SPL option on the ESBC to disable incoming INVITE validation. This feature makes use of the Control-Surr-Reg SPL, requiring the additional configuration noted below. When you configure this feature, the ESBC does not attempt to match the incoming R-URI against the random user part received while performing the Surrogate Registration SPL feature processing.

Although the surrogate registration SPL feature applies to both NTT and KDDI environments, this contact validation exclusion feature applies only to KDDI environments.

As stated above, when you deploy the surrogate registration feature using SPL, the ESBC compares the random contact generated during registration against the value of the user part of incoming Invite’s RURI. If this comparison fails, the ESBC suppresses this call. Some deployments, however, need to use the SPL surrogate registration process without this validation.

To skip this validation, you set the dial-inservice-validation SPL option on the ingress realm-config. The syntax for setting the dial-inservice-validation option follows.

ORACLE(realm-config)# +spl-options +dial-inservice-validation

In addition, configure the same options described for the surrogate registration feature on the applicable realm-config elements. This results in these options set on both the applicable sip-interface and realm-config:

• dyn-contact-start—Configure on the realm-config facing the CUCM realm.
• dyn-contact-method=randomseed—Configure on the realm-config facing the KDDI trunk.

When you include this configuration with the Surrogate Registration SPL feature, the ESBC continues to perform surrogate registration, sending REGISTER messages to KDDI and processing the 200 OK responses. The difference is that the ESBC accepts corresponding INVITE messages, even when the user part of RURI in the INVITE does not match the stored user part of the 200 OK’s contact header.