Senior Technical Support Engineer (SIP / VoIP / FoIP)
T38Fax.com
Technical Support Engineer
T38Fax is seeking an experienced Technical Support Engineer with a wealth of experience troubleshooting SIP / VoIP / FoIP issues in a customer-facing role. We're excited to be scaling our customer support team to keep up with the rapid growth of our popular T.38 Fax Over IP (FoIP) service. In this senior-level role we expected you to be well-versed in fundamental network concepts, with a demonstrated history of troubleshooting customer SIP and VoIP calls. The ideal candidate will also have experience diagnosing facsimile transmissions over SIP, especially if that experience involved T.38 Fax Over IP sessions.
Fans of John Oliver's "How Is This Still A Thing" segments might be amused to learn that fax remains deeply entrenched in the way many companies transact their daily business. Indeed, it seems fax is still very much a thing! In its annual report on the fax industry, Business Research Insights reports that the global fax market size was 2.36 billion in 2023 and is projected to reach 4.25 billion by 2032 at a compound annual growth rate (CAGR) of almost 7%. It's especially surprising, then, that most modern VoIP/SIP and cloud-based phone companies neither support fax over SIP nor understand how they might do so (until we show them how easy it is). Our fax-approved SIP trunks are ready to go today and fill a vital need in a growing and underserved industry that shows no signs of slowing down for many years to come.
About You
As a Technical Support Engineer you will be responsible for diagnosing and resolving customer issues related to SIP trunking, T.38 fax transmissions, call quality, and network configurations. You will work closely with customers, internal teams, and vendors to ensure seamless communication experiences. You are a proud, card-carrying tech-geek with a superhero's penchant for helping others. You breathe all things engineering, innovation, and data. Logic is your friend, and you use it generously. Equipped with an entrepreneurial attitude, you are relentlessly energetic and excited by new challenges. If you aren't multi-tasking, it means you are under-challenged. You don't just capture packets, you use science (not superstition) to tame them.
Your Mission
This is absolutely not an IT help-desk role. We call our support team 'engineers' because of the highly technical nature of troubleshooting SIP and T.38 at industrial scale. You will:
- Provide Escalated (Tier 3) support for FoIP and SIP-related technical issues via email, phone and case management system (Zendesk).
- Diagnose and troubleshoot SIP signaling, call setup failures, one-way audio, jitter, latency, and packet loss.
- Analyze SIP traces, PCAP captures, and logs using tools like Wireshark and tcpdump.
- Support T.38 Fax Over IP (FoIP) implementations, troubleshooting failed fax transmissions and improving reliability.
- Work with PBX systems (Asterisk, FreePBX, 3CX, etc.), VoIP gateways, and SBCs.
- Assist customers with network configurations, NAT traversal and firewall rules.
- Escalate complex issues to engineering teams and collaborate with vendors as needed.
- Take ownership of reported customer issues and see problems through to resolution, ensuring proper recording and closure of all issues.
- Write documentation, knowledge base articles and FAQs, and document troubleshooting steps, best practices and solutions in the company's knowledge base for use by both internal staff and customers.
- Test interoperability of new VoIP/FoIP equipment and create user guides for various IP-PBX and SIP-compatible devices for use with our SIP Trunking service.
Qualifications
Expert-level support is a core component of our brand and is deeply ingrained in our culture. We look for a mix of the technical expertise, troubleshooting skills, and industry knowledge that will be needed to solve complex problems, including:
- Bachelor's Degree in Computer Science or related field, or combination of education and experience may be considered.
- Solid understanding of networking fundamentals (TCP/IP, DNS, DHCP, NAT, VPNs and firewall rules) and networking protocols, in particular VoIP/SIP.
- Experience with fax and/or FoIP a plus.
- Experience with Wireshark.
- Experience with Asterisk, Kamailio, FreeSWITCH, OpenSIPS, or cloud-based VoIP APIs (Twilio, Plivo, Telnyx, etc.).
- Working knowledge of Linux/Unix Operating System.
- Careful, methodical approach to troubleshooting complex technical issues.
- Experience with help desk ticketing systems (Zendesk, Jira, ServiceNow, etc.).
- Excellent written and verbal communications including the ability to explain complex technical concepts to customers.
- Excellent customer-facing skills.
Your Style
- Customer satisfaction is your goal, and you pursue it relentlessly
- You have an unquenchable desire to learn
- You communicate clearly and concisely with technical and non-technical audiences
- You are a multitasker with the ability to properly prioritize
- You happily follow established procedures, but know when to propose improvements
Our Offer
- Competitive salary with annual profit-sharing bonus
- Casual, informal work environment
- Flexible working arrangements (remote/hybrid options)
- Generous PTO allowance
- Healthcare
- 401(k)
- Flyers tickets with VIP parking
- A team of aces
- An open mind for new ideas and methodologies
Work Location & Compensation
This role can be performed remotely, hybrid, or in-office at our headquarters in Conshohocken, just outside of Center City Philadelphia. Candidates who choose to work in-office may be eligible for higher compensation, additional in-office perks, and increased collaboration opportunities. Compensation for remote employees is adjusted based on market rates for their location.
Our Story
Founded in 2016 and based in Conshohocken just outside of Philadelphia, PA, T38Fax provides fax-optimized SIP trunks to business customers within the US and Canada. We're similar to a Voice Over IP (VoIP) phone company, except our network is optimized for fax transmissions instead of voice. Our product is unique and in high demand, we're one of just a handful of companies that do this worldwide, and we have an exceptional reputation in the industry. In 2020, T38Fax was recognized by Inc. Magazine as one of the fastest growing companies in the US and by the Entrepreneurs Forum of Greater Philadelphia (EFGP) as one of the 100 fastest growing companies in the Philly metro area.
We remain small and agile, which makes this a fun, dynamic, and challenging place to work. The work environment is casual and, for the most part, informal. Expectations are high and excellence is encouraged and rewarded. We strive to make sure that we have a team-oriented group that can also work well independently. If you enjoy working in a high freedom, high demand environment with a small but talented group of people this may just be the job for you.
We offer a competitive benefits package including healthcare, a substantial number of paid days off (PTO), a generous profit-sharing plan, and access to our Flyers season tickets for yourself and a guest. We're a great group of people doing exceptional things for our customers and having fun doing it. Like any emerging growth company, this will be hard work, but more importantly, it will be fun and immensely rewarding. We think you already know if this is a position for you, and if so, we look forward to reviewing your application!
Are you The One? If so, please send your battle plan and a certificate of your superpowers. Alternatively, a cover letter and resume will suffice. At least for now.
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