3.3.1 UDR Lookup Flow

vENUM Response query flow is as follows:

1. When ENUM query is received on ENUM MP on vENUM, then retrieve the DN from the ENUM query and lookup UDR for required DN.

   If UDR is not connected to ENUM MP, then send RCODE=2 in ENUM response, otherwise proceed.

2. If DN is not found in UDR, then apply ENUM default action, otherwise proceed with the next step.
3. If ENUM Record is associated with MSISDN block in Subscriber profile, use this ENUM record while generating ENUM response, otherwise proceed with the next step.
4. If ENUM Record is associated with SPRN or GRN Entity profile, then use the preferred profile while generating ENUM response, otherwise proceed with the next step.
5. If ENUM record is not present in both subscriber and entity profile, then use default ENUM Profile from ENUMOPTION MO on ENUM MP.

The following is the flowchart for vENUM Response query.

Figure 3-1 vENUM Response