© Made by Adam Bellanger

A complete telephony migration lab: Alcatel-Lucent OXO Connect IP-PBX, carrier SIP trunk, voice VLAN and 40 IP phones.

LabA lab: designed and documented end to end, modelled on the installations I work on as an apprentice. Not a client engagement.

Stack

Telephony
  • Alcatel OXO Connect
  • OMC
  • SIP trunk
Networking
  • VLAN 802.1Q
  • LLDP-MED
  • PoE+
  • QoS DSCP
  • FortiGate

Context

Scenario: a 40-employee company on two floors, with an ageing PBX at end of life and ISDN lines set to disappear as France shuts down its copper network. Goal: move to IP telephony without changing numbers, with a reception desk, departments reachable directly and no visible outage for callers.

Role

Lab project: sizing, numbering plan, voice network design and cutover procedure, documented as for a real commissioning. It is the kind of installation I work on as an apprentice; this file formalises it end to end.

Architecture

  1. Carrier

    8-channel SIP trunk, ported numbers

  2. FortiGate

    SIP ALG disabled, rules towards the carrier

  3. Huawei PoE+ switches

    Voice VLAN 20 via LLDP-MED, DSCP EF / CS3

  4. OXO Connect

    IP licences, auto attendant, hunt groups, voicemail

    40 IP phones

    Offices + operator phone at reception

    Analogue ports

    Fax and alarm

Phones and IP-PBX share the voice VLAN; PCs stay on the data VLAN, plugged in behind each phone's built-in switch.

Numbering plan

NumberAssignmentBehaviour
Main lineMain direct numberGreeting, then auto attendant: 1 Sales · 2 Support · 3 Accounts
201 – 222First-floor phones (22)Individual direct number per phone
301 – 318Second-floor phones (18)Individual direct number per phone
500Reception hunt groupRings all phones, overflows to 510 after 20 s
510Sales hunt groupRound robin, voicemail after 30 s
0Outside lineOut through the SIP trunk

Challenges

Sizing the OXO Connect (chassis, boards, IP licences and a SIP trunk for 8 simultaneous calls); isolating voice in a dedicated VLAN pushed automatically to the phones via LLDP-MED; protecting call quality with DSCP EF marking on RTP and CS3 on signalling, honoured end to end; disabling the firewall's SIP ALG, a classic cause of one-way audio; and planning an out-of-hours cutover with number porting and a rollback plan.

Outcome

A full commissioning file: architecture diagram, numbering plan, voice addressing, OXO configuration (auto attendant, hunt groups, day/night schedules, voicemail) and cutover procedure. Ready to reuse as the basis for a real installation.

Highlights

  • 40 PoE+ IP phones, voice VLAN assigned automatically (LLDP-MED)
  • 8-channel SIP trunk, direct numbers kept through porting
  • Reception: greeting, 3-option auto attendant, overflow to a hunt group
  • Out-of-hours cutover with a documented rollback
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