VoIP Platform / Infrastructure Engineer - Base

BMW TechWorks India Private Limited; Pune District; On-site; INR 2,500,000 - 4,000,000; Full time

Job summary

BMW TechWorks India Private Limited in Pune seeks a VoIP Platform / Infrastructure Engineer to design, deploy, and operate large-scale telecom platforms. You will work across Asterisk, Kamailio, SBCs, and security-enabled SIP environments, ensuring high availability and robust routing.

Candidates should have 9–15 years of hands-on experience, strong Linux/automation skills (Python, Cron), and deep knowledge of SIP, TLS/SRTP, DNS, NTP, and disaster recovery.

Qualifications

• Strong experience with VoIP platforms and telephony routing systems.
• Deep knowledge of Asterisk internals and dialplan logic.
• SBC/Session Border Controller operations and media anchoring.
• Proficiency with SIP/TLS/SRTP security and certificate management.
• Experience with Linux-based automation and scripting (Python).

Responsibilities

• Product Knowledge (Installation, Configuration, Operations, Maintenance).
• Asterisk (deep): Strong operational and development-level understanding of Asterisk internals, especially large and complex dialplans with business logic.
• Dialplan engineering: Design, refactor, and troubleshoot multi-branch call flows, failover paths, and edge-case routing behavior.
• Call encryption: Handling TLS and SRTP in production, including certificate lifecycle and interop troubleshooting.
• SBC stack: Kamailio for SIP routing/policy and RTPengine operation for media anchoring, NAT traversal, and media security.
• SIP Capture and Troubleshooting
• PCAP and Wireshark: Packet-level troubleshooting for SIP/RTP/SRTP/TLS issues.
• Homer SIP capture: Use of capture/visualization to correlate signaling and media events.
• End-to-end call tracing: Correlate Call-ID, tags, branch params, dialogs across Asterisk, Kamailio, SBC.
• Test strategy depth: SIP integration tests and regression suites for dialplan logic.

Skills

Asterisk internals

Kamailio SIP routing

SBC/Media anchoring

SIP/TLS/SRTP protocols

Python scripting

Tools

Asterisk

Kamailio

SBC stack

Wireshark

Terraform

AWS

CI/CD

Job description

VoIP Platform / Infrastructure Engineer ...

BTWI/VP-IE-B/1840180

• Digital Car
• Pune

Posted On 27 Oct 2026

End Date 10 Nov 2026

Required Experience 9 - 15 years

Skills

Skill

Job Description

• Product Knowledge (Installation, Configuration, Operations, Maintenance)
• Asterisk (deep): Strong operational and development-level understanding of Asterisk internals, especially large and complex dialplans with business logic.
• Dialplan engineering: Ability to design, refactor, and troubleshoot multi-branch call flows, failover paths, and edge-case routing behavior.
• Call encryption: Practical handling of TLS and SRTP in production, including certificate lifecycle and interop troubleshooting.
• SBC stack: Solid Kamailio skills for SIP routing/policy and RTPengine operation for media anchoring, NAT traversal, and media security.

• SIP Capture and Troubleshooting
• PCAP and Wireshark: Confident packet-level troubleshooting for SIP, RTP, SRTP, TLS handshake issues, retransmissions, and one-way audio.
• Homer SIP capture: Efficient use of capture/visualization to correlate signaling and media events across distributed components.
• End-to-end call tracing: Ability to correlate identifiers (Call-ID, tags, branch params, dialogs) across Asterisk, Kamailio, and SBC layers.
• (- Test strategy depth: SIP integration tests, regression suites for dialplan logic, and synthetic call monitoring in production-like environments.)

• Operating System and Automation
• SUSE Linux (LPIC-1 level or higher): Comfortable with package/service management, networking, process control, and system diagnostics.
• Python (basic): Scripting for automation, validation, and lightweight operational tooling.
• Cron and shell scripting: Building and maintaining jobs for log rotation, housekeeping, health checks, and routine maintenance tasks.
• Log and filesystem hygiene: Managing retention, rotation policies, and storage pressure under high call volume.

• Network and VoIP Foundations
• TCP/UDP deep understanding: Behavior under packet loss, reordering, retransmissions, and impact on signaling/media quality.
• VoIP protocols (deep): SIP, RTP, SRTP, TLS, mTLS, codec negotiation, DTMF transport, NAT and firewall implications.
• SIP protocol internals (RFC-level): Transaction/dialog state machines, timers, forking, early media, PRACK/100rel, session timers.
• Network services (deep): DNS behavior (including latency/caching/failover effects), NTP sync relevance for logs/traces, and routing basics.
• High availability and disaster recovery: Active-active/active-passive design, failover testing, backup/restore drills, RTO/RPO ownership.

• AWS and Infrastructure as Code
• Core AWS: EC2, VPC, Route 53, Security Groups, CloudWatch, and basic Lambda usage.
• Resilience testing: AWS FIS basics for controlled fault injection and validation of failover behavior.
• Secrets and access management: IAM least privilege, secret rotation, certificate/key lifecycle, and auditability.
• Terraform: Versioned, repeatable infrastructure provisioning and safe change workflows (plan/review/apply discipline).

• DevOps and Reliability (Mandatory for Dev + DevOps Collaboration)
• CI/CD pipelines: Build, test, security checks, and controlled release promotion.
• Observability operations: Metrics, logs, traces, and alert tuning to reduce noise and improve incident response.
• Incident response: Structured triage, rollback decision-making, and post-incident analysis.
• Release and change governance: Blue-green/canary strategy, maintenance window practices, and backward-compatible migration planning.