Position : VoIP / SIP Engineer IMS/5G Core exposure

Experience : 5+ Years

Location : Hyderabad

Job Summary :

We are seeking a skilled VoIP/SIP Engineer with strong expertise in SIP device onboarding, VoIP troubleshooting, IMS/VoLTE technologies, and SBC integrations.

The ideal candidate will be responsible for onboarding and validating SIP endpoints, troubleshooting complex signaling and media issues, and ensuring interoperability between SIP devices and the enterprise communication platform.

Experience with Cisco Unified Communications (CUCM), IP Telephony, Wireshark analysis, and telecom protocols is highly preferred.

Key Responsibilities :

SIP Device Onboarding & Certification :

- Configure and onboard SIP devices such as IP Phones, ATAs, Gateways, Softphones, and Video Endpoints.

- Perform SIP device provisioning, registration, authentication, and feature validation.

- Configure SIP parameters including :

1. SIP Registration

2. Authentication Credentials

3. TLS/SSL Certificates

4. Codec Negotiation (G.711, G.729, Opus, etc.)

5. DTMF Methods (RFC2833, SIP INFO)

6. Dial Plans and Routing Rules

7. Call Features and Device Settings

- Validate device interoperability with Session Border Controllers (SBCs) and VoIP platforms.

- Define and execute certification test cases for newly onboarded SIP devices.

- Create and maintain onboarding documentation, configuration guides, and certification reports.

SIP / VoIP Troubleshooting :

- Analyze and troubleshoot :

1. SIP Registration Failures

2. Call Setup and Call Teardown Issues

3. One-Way Audio / No Audio Scenarios

4. Codec Negotiation Failures

5. RTP Media Flow Problems

6. NAT Traversal Issues

7. TLS/SRTP Connectivity Issues

8. SIP Interoperability Problems

- Perform root cause analysis using SIP traces and protocol logs.

- Collaborate with OEM vendors and internal engineering teams to resolve device-specific issues.

SIP Signaling & Packet Analysis :

- Capture and analyze network traffic using Wireshark and PCAP tools.

- Interpret SIP call flows including :

1. INVITE

2. REGISTER

3. SUBSCRIBE

4. NOTIFY

5. REFER

6. OPTIONS

7. BYE

8. CANCEL

- Debug signaling and media issues through packet-level analysis.

- Generate detailed troubleshooting reports based on call traces.

IMS / VoLTE / 4G / 5G Core Integration :

- Understand IMS architecture and SIP signaling within telecom networks.

- Exposure to :

1. VoLTE Call Flows

2. IMS Registration Procedures

3. P-CSCF, I-CSCF, S-CSCF Functions

4. Diameter Signaling Basics

5. 4G EPC and 5G Core Concepts

- Validate SIP devices in IMS and VoLTE environments.

- Analyze SIP interactions between endpoints and telecom core network elements.

CUCM & IP Telephony Administration :

- Install, configure, and maintain Cisco Unified Communications Manager (CUCM).

- Configure and register Cisco IP Phones.

- Manage SIP trunks and dial plans within CUCM.

- Perform user provisioning and endpoint configuration.

- Troubleshoot SIP registration and call routing issues in Cisco environments.

- Support enterprise voice infrastructure and IP telephony deployments.

Device Configuration & UI Development :

- Create device configuration templates based on OEM specifications.

- Develop and customize onboarding templates for various SIP devices.

- Create and modify HTML-based UI pages used for device onboarding and setup workflows.

- Maintain device-specific configuration repositories and documentation.