Bulgaria Vivacom Equipment Replacement Project – Configuration Migration

The broadband network renovation and equipment replacement project of Vivacom Bulgaria only covers its FBB Access Network and FBB Metropolitan Area Network (MAN). In accordance with the confirmed renovation and replacement scheme under which broadband services of the FBB access network are deployed to remote drop sites while voice services remain unchanged, legacy MSAN devices in the FBB access network shall be replaced by new MSAN devices at their original locations. Part of the broadband services carried on legacy MSANs need to be migrated to newly deployed VDSL equipment, while voice services and the remaining broadband services on legacy MSANs shall be cut over to the new MSANs.

Subscriber service data borne by each legacy MSAN is extracted from Vivacom’s subscriber account system. Combined with the service configurations on each legacy MSAN, the data is sorted out to record broadband-only, voice-only and dual-service (broadband + voice) information of every subscriber in each residential area under the corresponding legacy MSAN, as well as MDF site information and MDF terminal information. Based on the sorted data, it is further confirmed whether each subscriber’s broadband service will be migrated to a new VDSL device or cut over to the new MSAN. For newly deployed VDSL equipment, each migrated broadband service is treated as a brand-new service activation and configured accordingly.

Voice services remain unchanged and only need to be cut over from legacy MSANs to the new MSANs deployed at the original sites. To reduce cutover complexity, service grooming for voice services is not performed synchronously. Instead, jumper cables are used to physically transfer subscriber access lines from legacy MSANs to new MSANs to complete physical service cutover. In addition, all configurations of each legacy MSAN shall be converted to matching configurations for the new MSANs in advance; during conversion, configuration entries for broadband services migrated to VDSL equipment shall be removed from the new MSAN configuration files.

Service Grooming: Upon initial service activation, services are configured sequentially by ports on service boards. Over time, some ports are released after subscribers cancel their services, leaving idle ports on each service board. Service grooming refers to reorganizing and consolidating remaining services onto fewer ports, so as to reduce the number of occupied service boards and free up board slots for power saving or deployment of other service boards.

Per the confirmed FBB MAN renovation scheme, which only replaces legacy hardware with new high-performance, high-bandwidth devices without modifying network architecture or services, legacy LAN switches and BRAS devices in the FBB MAN shall be replaced by new LAN switches and BRAS devices at original positions.

Prior to replacing legacy LAN switches, new uplink connections for newly deployed VDSL equipment and their broadband services are added on the legacy LAN switches, while configuration entries corresponding to broadband services migrated to VDSL equipment are deleted from the ports connecting to MSANs.

After the deployment of VDSL equipment and replacement of legacy MSANs are fully completed, all configurations on legacy LAN switches shall be converted one by one for the new LAN switches, followed by the physical replacement of legacy LAN switches. Likewise, all configurations on legacy BRAS devices shall be converted to the configuration format of new BRAS devices before the BRAS replacement work is carried out.