Asterisk & VoIP Systems Engineer

Bir Turkcell grup şirketi olarak 1999 yılında kurulduğumuzda amacımız hep eşsiz bir müşteri deneyimi yaşatmaktı.

Yıllar geçse de amacımız hiç değişmedi ve bugün biz yine aynı odak noktası ve artan heyecanımızla; toplam 15 lokasyonda, 16 binden fazla çalışanımızla firmaların müşteri deneyimini iyileştirmeye devam ediyoruz.

Telekom sektöründeki köklü tecrübemizin yanı sıra; finans, sigorta, e-ticaret, perakende, ulaştırma, hızlı tüketim, havacılık, otomotiv, teknoloji, enerji ve kamu sektörlerinde hizmet vermekteyiz.

Eşsiz müşteri deneyimine ulaşabilmek için geleneksel bir kanal olan ve Ana Hizmetlerimizin altında yeralan çağrı hizmetlerimize; Dijital, Teknolojik ve Danışmanlık Hizmetlerimizi de ekleyerek güçlendirdik.

Daha hızlı, tasarruf sağlayan, kolay ulaşılabilen bir müşteri deneyimi sunmak için RPA (Robotik Süreç Otomasyonu), Dijital Yardım Masası, Social Sniffer, Konuşma Analizi, Bulut Santral, Chat & Chat Bot gibi dijital hizmetlerimizi kullanıyoruz.

Müşteri deneyimi uçtan uca bir süreç olduğu için; Deneyim Tasarımı, Kalite & Araştırma Yönetimi gibi danışmanlık hizmetlerimiz ile bu deneyimin tasarım aşamasını da analitik bir bakış açısıyla sunuyoruz.

Ana hizmetlerimiz içerisinde yer alan çağrı hizmetlerimizi ise sadece ses kanalı ile vermekle kalmayıp, görüntülü görüşme ve otomatik sesli yanıt sistemleri (IVR) ile destekleyerek müşterilerimize eşsiz bir deneyim yaşatıyoruz.

‘’Turkcell İletişim Hizmetleri A.Ş. ve Grup Şirketleri, kişisel verilerinizin hukuka uygun olarak toplanması, saklanması, paylaşılmasını sağlamak ve gizliliğini korumak amacıyla mümkün olan en üst seviyede güvenlik tedbirleri almaktadır. İletmiş olduğunuz özgeçmişiniz doğrultusunda, kişisel verileriniz veri sorumlusu olarak Turkcell ve Grup Şirketleri tarafından toplanarak işlenebilecektir. Kişisel verilerinize ilişkin detaylı bilgi almak, Kanun’un 11. maddesinde düzenlenen haklarınızı kullanmak ve başvuru yöntemlerini öğrenmek için Turkcell Çalışan Adayı Aydınlatma Metni'ni ‘’https://globalbilgi.com.tr/wpcontent/uploads/2023/12/TURKCELL\_Calisan\_Adayi\_Aydinlatma\_Metni.pdf’’ internet adresimizden inceleyebilirsiniz.”

Job Description

We are looking for a Senior Asterisk & VoIP Systems Engineer to play a key role in the development, integration, operation, and technical support of Enterprise PBX, Call Center, and Unified Communications platforms.

This position involves managing application and infrastructure layers, performing end-to-end technical analysis and Root Cause Analysis (RCA), operating highly available systems, and developing operational automation.

Please Note: This is not a GUI-focused PBX administration role (FreePBX, Issabel, Elastix, etc.). Hands-on experience with Pure Asterisk in production environments is required.

Responsibilities

• Manage installation, configuration, operation, integration, and technical support of Enterprise PBX, Call Center, and Unified Communications platforms.
• Participate in the design, deployment, development, integration, and operation of systems running on Pure Asterisk.
• Develop CRM, ERP, and internal application integrations using Dialplan, AGI, AMI, and ARI.
• Compile Asterisk from source and manage modules, patching, upgrades, and migrations.
• Manage Asterisk Realtime Architecture (ARA) and database integrations.
• Configure and integrate SIP Trunks, SBCs, and FXO/FXS/PRI Gateways.
• Manage SIP/VoIP integrations with telecom operators and ITSPs.
• Deploy and operate Kamailio/OpenSIPS for SIP proxy and routing requirements.
• Perform packet-level analysis and RCA using Wireshark, tcpdump, and sngrep.
• Troubleshoot VoIP issues including jitter, packet loss, latency, one-way/no-way audio, RTP, codec negotiation, DTMF, and call setup failures.
• Manage Red Hat Enterprise Linux / Linux servers and troubleshoot system, service, resource, logging, and performance issues.
• Develop operational tools and automation using Bash/Shell, with Python, PHP, or C where required.
• Support Java/Tomcat-based applications and troubleshoot related application and JVM issues.
• Manage centralized logging and analysis using Elasticsearch.
• Monitor systems and applications using Zabbix, SolarWinds, and similar tools.
• Contribute to Load Balancing, High Availability, failover, and Disaster Recovery activities.
• Troubleshoot network and VoIP issues involving TCP/IP, DNS, TCP/UDP, NAT, VLAN, routing, and QoS.
• Work with MySQL/PostgreSQL databases and support Azure DevOps / TFS-based deployment and release processes.
• Perform end-to-end troubleshooting and RCA across application, system, network, database, and VoIP layers.
• Take an active role in Incident, Problem, and Change Management processes.
• Prepare and maintain technical documentation, troubleshooting guides, and runbooks.
• Collaborate with Software, DevOps, System, Network, and Telecom teams to resolve critical technical issues.

Qualifications

Technical Competencies (Core Requirements)

• Proven hands-on experience in Telecommunications, VoIP, Enterprise PBX, or real-time communication systems.
• Advanced hands-on experience with Pure Asterisk in production environments.
• Experience with high-availability Asterisk architectures, failover, SIP trunk redundancy, and Disaster Recovery.
• In-depth expertise in Dialplan, AGI, AMI, ARI, and Asterisk Realtime Architecture (ARA).
• Strong understanding of SIP, PJSIP, SDP, and RTP/RTCP.
• Hands-on experience with PJSIP/res_pjsip, including endpoint, AOR, authentication, identify, and transport configuration.
• Hands-on experience with SIP Trunks, SBCs, and FXO/FXS/PRI Gateways.
• Experience with Asterisk CDR/CEL, call records, and call-flow analysis.
• Strong understanding of SIP signaling, call flows, SIP response codes, and SDP negotiation.
• Experienced in Red Hat Enterprise Linux / Linux system administration and proficient in Bash/Shell scripting.
• Strong command of TCP/IP, DNS, UDP, NAT, VLAN, routing, and QoS for VoIP troubleshooting.
• Hands-on experience with packet-level analysis (sngrep, tcpdump, Wireshark) and systematic RCA.

Education & Certifications

• Bachelor's degree in Computer Science, Software Engineering, Telecommunications Engineering, Electronics & Communication Engineering, Electrical & Electronics Engineering, or a related field.
• 5+ years of hands-on experience designing, developing, and operating high-traffic Asterisk-based PBX, Call Center, or VoIP platforms.
• dCAP (Digium Certified Asterisk Professional) or current Sangoma/Asterisk certifications are preferred.
• CCNA / CCNP Collaboration or similar Network/VoIP certifications are a plus.
• RHCSA / RHCE / LPIC or similar Linux certifications are a plus.

Nice-to-Have Skills

• SIP/VoIP integration experience with telecom operators and ITSPs.
• Advanced hands-on experience with SBC products.
• Advanced SIP routing experience with Kamailio or OpenSIPS.
• Knowledge of Docker and Kubernetes.
• Experience with SIP/RTP/WebRTC based real-time communication platforms.
• Experience with Apache Tomcat and Java-based applications.
• Knowledge of JVM and application performance tuning.
• Automation development experience using Python, PHP, or C.
• Experience with Elasticsearch and centralized logging.
• Experience with Zabbix, SolarWinds, or similar monitoring tools.
• Familiarity with Azure DevOps / TFS and release processes.
• Experience with MySQL and/or PostgreSQL.
• Knowledge of TLS/SRTP, iptables, and fail2ban.

Personal Competencies

• Strong analytical thinking and problem-solving skills.
• Ability to perform systematic analysis and RCA on complex technical issues.
• Ability to analyze relationships between application, system, network, database, and VoIP layers.
• Comfortable working in critical, high-availability, 24/7 environments.
• Effective communication and coordination skills across technical teams.
• Strong technical documentation and knowledge-sharing skills.
• Professional working proficiency in technical English.
• Willingness to participate in an on-call rotation when required.

Technology Ecosystem

• VoIP / Telecom: Asterisk · PJSIP · SIP · RTP/RTCP · SDP · WebRTC · STUN/TURN/ICE · SIP Trunks · SBC · FXO/FXS/PRI · Kamailio/OpenSIPS
• Application / Middleware: Java · Apache Tomcat · AGI · AMI · ARI · CRM/ERP Integrations
• System / Security: Red Hat Enterprise Linux · Linux · Bash · iptables · fail2ban · TLS · SRTP
• Network: TCP/IP · DNS · HTTP/HTTPS · TCP/UDP · NAT · VLAN · Routing · QoS · Load Balancing
• Database: MySQL · PostgreSQL · SQL · Asterisk Realtime Architecture · CDR/CEL