CBSD Serial Number Construction and Parsing

Serial Number Construction and Parsing

CBSD Provisioning Guideline
Key Bridge Technical Note

1. Purpose

This guideline defines how Key Bridge constructs, interprets, and normalizes the cbsdSerialNumber field during CBSD registration and subsequent SAS operations. It ensures consistent identity handling for multi-sector, Passive DAS, and remote radio deployments while remaining fully aligned with industry recommendations.

2. References

3. Identifier Construction (per WINNF-TR-5001 §5.3)

WINNF-TR-5001 recommends appending sector and/or transmission-point identifiers to the manufacturer serial number using the colon (:) delimiter:

• ManufacturerSerialNumber:SectorID
• ManufacturerSerialNumber:TPID
• ManufacturerSerialNumber:SectorID:TPID

Key Bridge adopts this construction rule without modification.

4. Recognized Serial Number Pattern

Field experience has shown that some radio firmware (notably certain Nokia platforms) appends a profile or air-interface suffix that is invisible to the installer. The resulting string presented to the SAS may therefore contain both a vendor-generated suffix and installer-generated WINNF suffixes.

Key Bridge recognizes the following formal pattern:

[serial](.[type])?(:[sector])?(:[tpid])?

5. Key Bridge Parsing Implementation

Key Bridge Domain Proxies and SAS-facing components apply a strict two-stage parse:

Stage 1 – WINNF delimiter
Split the entire cbsdSerialNumber on the colon character (:).

Stage 2 – Vendor suffix
Examine only the first token. If it contains a non-alphanumeric character (most commonly .), split on the last such character to separate the true manufacturer serial number from any firmware/profile suffix.

Pseudocode:

tokens ← split(cbsdSerialNumber, ":")

base   ← tokens[0]
sector ← tokens[1] if present
tpid   ← tokens[2] if present

if base contains non-alphanumeric character:
    serial, type ← split_on_last_non_alphanumeric(base)
else:
    serial ← base
    type   ← null

The resulting serial value is the identity used for matching against CPI-signed registration data. The optional type, sector, and tpid components are retained as metadata for inventory, grouping, and operational support systems.

6. Examples

7. Recommendations for Installers and CPI

1. Enter the serial number exactly as printed on the radio label (or as reported by the manufacturer’s inventory system). Do not attempt to anticipate firmware suffixes.
2. When multiple sectors or remote radio heads require distinct CBSD identities, append the Sector ID and/or TP ID using the colon delimiter exactly as specified in WINNF-TR-5001 §5.3.
3. Do not insert additional delimiters or modify the manufacturer serial number.
4. Record the full constructed string (including any :sector / :tpid) in the installation records for future reference.

8. Notes

• Key Bridge normalizes the serial number for SAS identity matching while preserving the original string for audit and support purposes.
• The parsing logic is deliberately conservative: only the first token is examined for a vendor suffix, and only non-alphanumeric characters are considered.
• This guideline applies to all CBSD registrations processed through Key Bridge SAS and Domain Proxies and is recommended for direct CBSD-to-SAS registrations where the radio firmware may mutate the serial number.