5.2 HNB Registration

25.4673GPPRelease 17Stage 2TSUTRAN architecture for 3G Home Node B (HNB)

5.2.1 General

The following section illustrates the case when the HNB registers with the HNB-GW. The HNB registration procedure serves the following purposes:

– It informs the HNB-GW that a HNB is now available at a particular IP address.

5.2.2 HNB Registration procedure

Figure 5.2.2-1: HNB Registration procedure.

1. HNB initialization is performed to obtain HNB configuration from the HNB Management System (HMS). Similarly, HNB-GW discovery is performed to obtain the initial serving HNB-GW information.

2. The HNB establishes a secure tunnel to the SeGW of the serving HNB-GW.

NOTE: This step may be omitted if the secure tunnel happens to be the same tunnel that is already established to contact the HMS.

3. The HNB sets up an SCTP transport session to the registered port on the serving HNB-GW for Iuh.

4. The HNB then attempts to register with the serving HNB-GW using an HNB REGISTER REQUEST message. The message contains:

a. HNB Location Information: The HNB provides location information via use of one or more of the following mechanisms:

i. Detected macro-cell coverage information (e.g. GERAN or UTRAN cell information).

ii. Geographical co-ordinates (e.g. via use of GPS, etc).

iii. Internet connectivity information (e.g. IP address), provided, the resulting location information is at least as accurate as location determination based on macro-cell coverage information, whether or not there is macro cell-coverage available at the location of the HNB (e.g. as determined by point i above).

b. HNB Identity: the HNB has a globally unique and permanent identity.

c. HNB Operating Parameters: Such as the selected LAC, RAC, SAC, PLMN Id, Cell Id, etc.

d. HNB operating mode (optional): HNB CSG-Id or access mode (open, closed or hybrid).

e. HNB’s own IP address for direct Iurh connectivity (if Iurh connectivity is supported by the HNB).

f. CELL_FACH mobility support, if the HNB supports mobility for CELL_FACH, CELL_PCH and URA_PCH.

g. Additional Neighbour Information: The HNB may indicate additional neighbour information necessary for CELL_FACH mobility. This additional information may be used by HNB-GW to manage the assignment of S-RNTI prefixes.

5a. The HNB-GW may use the information from the HNB REGISTER REQUEST message to check whether the HNB registration can be accepted (e.g. to check whether a particular HNB is allowed to operate in a given location, etc). The HNB-GW shall verify the HNB identity, the validity of the indicated cell access mode and, for CSG cells, the CSG ID as specified in TS 33.320 [16]. If the HNB-GW accepts the registration attempt it shall respond with a HNB REGISTER ACCEPT message. If the HNB-GW has capability to de-multiplex, the HNB-GW may include a mux port in the HNB REGISTER ACCEPT message. The HNB shall include the RNC-ID provided by the HNB-GW within relevant RANAP messages in order to identify the HNB-GW during mobility procedures and within RRC messages, where the RNC-ID has to be contained within the most significant bits of the Cell Identification and be part of the U-RNTI.

In order to support CELL_FACH/CELL_PCH/URA_PCH mobility, the S-RNTI Prefix value is sent to the HNB. The HNB that supports S-RNTI prefix assignment shall include the S-RNTI prefix in the most significant bits of S-RNTI part following the RNC ID bits in the U-RNTI.

The HNB-GW may provide its IP address in order to allow the HNB to either establish Iurh-connectivity via the HNB-GW or to establish connectivity to an RNC via the HNB-GW.

The HNB-GW ensures that the S-RNTI prefixes assigned to HNBs are unique within the URA Area/overlapping URA Areas. If supported, the HNB-GW may reuse the S-RNTI prefix across non overlapping areas.

5b. Alternatively, the HNB-GW may reject the registration request (e.g. due to network congestion, Exclude-listed HNB, unauthorized HNB location, etc). In this case, the HNB-GW shall respond with an HNB REGISTER REJECT indicating the reject cause.

6. If the HNB-GW had provided in the HNB REGISTER ACCEPT message the HNB-GW’s own IP address for Iurh connectivity via/to the HNB-GW, the HNB shall, if supported, set up an SCTP transport session to the port registered for Iurh.

NOTE: The HNB shall start broadcasting only after successful registration with the HNB-GW.