Branch network — interconnection and enterprise telephony
Twenty-two branches linked to head office, with unified telephony, backup paths and common supervision.
- Reference
- KP-2024-019
- Sector
- Finance and fraud prevention
- Country
- Mali
- Year
- 2024
- Duration
- 8 months
From branch to core, and what separates them, schematic
- 01Branches
- Handsets, counters and security equipment at one location. They do not all carry the same continuity requirement.
- 02Duplicated links
- A second link at the branches whose activity cannot tolerate interruption. Duplicating everywhere costs without adding anything where a stop is acceptable.
- 03Telephony core
- Made redundant at head office. Service depends on neither a single server nor a single room.
- 04Numbering plan
- A plan that is kept, forwarding that reads clearly, one voicemail. That is what users judge, not the make of the core.
- 05Segmentation
- Voice, office systems and security kept apart. A compromised office workstation does not reach the security equipment.
- 06Quality of service
- Voice goes before everything else on the link. Without prioritisation, one backup job is enough to make a call unusable.
- 07Supervision
- The state of every link and every handset. A branch that is cut off must be known before its manager calls.
01
The context
Each branch had its own subscription, its own switchboard and its own number. A link failure isolated the branch, and head office learned of it only through a customer call. Calls between branches went over the public network and were billed as such.
02
The mission
Interconnect the twenty-two branches, unify telephony under a single numbering plan, duplicate the links of the most exposed branches, and supervise the whole from head office.
03
The architecture
A redundant telephony core at head office, duplicated carrier links at the eight branches whose activity cannot tolerate interruption, and segmentation separating voice, office systems and security equipment. Supervision reports the state of every link and every handset.
04
Delivery
Rollout followed the branches' order of exposure rather than geography: the eight branches selected for duplicated links were handled first. Each cutover was preceded by a live rehearsal outside opening hours.
05
Results
A link failure is now known at head office before the first customer call, and eight branches keep running on their backup path. Internal calls no longer traverse the public network.
06
What we take from it
Rollout order is a design decision, not a logistical convenience. Handling the most exposed sites first surfaces the real difficulties while there is still budget to respond to them.
Results
- 22
- Branches interconnected
- 8
- Branches on duplicated links
- 8
- Months of rollout
Technologies
- Asterisk
- FreePBX
- MikroTik
- pfSense
- Zabbix
Solutions concerned
Why some clients are not named here
We design security systems and information systems for organisations whose public exposure is an operational risk. The discretion we apply to their projects is the discretion we will apply to yours. Identities, architectures and contractual documents are shared with an identified organisation as part of a pre-qualification.