DRIVENETS Software Engineer Interview: Questions & Prep (2026)

DriveNets builds cloud-native disaggregated networking software, letting telecom operators and cloud providers run carrier-grade routing on white-box hardware instead of proprietary gear. The company is headquartered in Israel with engineering teams spanning multiple countries.

As of July 2026, knok's job radar shows 41 open Software Engineer roles at DriveNets. The interview process is engineering-heavy, with a strong focus on networking protocols, Linux internals, and distributed systems. Candidates report a multi-stage process that typically includes a coding screen, a systems design round, and one or more deep-dive technical discussions.

Salary context from the broader market: Software Engineer roles in India currently sit at 6-12 LPA at entry level (0-2 years), 15-25 LPA at mid-level (3-5 years), 28-45 LPA at senior level (6-9 years), and 40-65+ LPA at lead or staff level (10+ years), based on live data across 5,395 Software Engineer jobs open as of July 2026.

Candidates interviewing at DriveNets typically encounter questions across three areas: networking fundamentals, systems-level programming, and distributed systems design. Below are the questions reported most often.

1. Explain how BGP establishes a neighbour relationship and what happens when it drops. DriveNets builds routing software, so BGP is core territory.

1. Walk me through what happens when a packet arrives at a router running a disaggregated NOS. Tests your understanding of the data plane and control plane split.

1. How does ECMP work, and what are its failure modes at scale? Equal-cost multipath is central to DriveNets' load-balancing story.

1. Design a high-availability control plane for a distributed router. A classic systems design question tailored to their product.

1. How would you detect and handle a silent packet drop in a distributed forwarding system? Tests observability thinking in networking contexts.

1. Describe a lock-free or wait-free data structure you have used in a performance-critical path. DriveNets cares deeply about data-plane throughput.

1. What is the difference between user space and kernel space networking, and when would you choose DPDK or XDP? Kernel bypass is a recurring theme in their stack.

1. How do you approach memory management in a C++ application that handles very high packet rates? They want to hear about custom allocators, pool allocation, and avoiding heap fragmentation.

1. Tell me about a distributed systems bug you debugged. How did you isolate the root cause? A behavioural question wrapped around systems depth.

1. How would you design a telemetry pipeline that streams interface counters from a large fleet of router nodes to a central analytics store? Tests streaming and scale thinking.

1. What trade-offs do you consider when choosing between gRPC and a custom binary protocol for control-plane messaging? Protocol design judgement.

1. How have you contributed to a large C++ or Go codebase used by multiple teams? How did you manage backward compatibility? Tests collaboration and engineering discipline.

Use the STAR format (Situation, Task, Action, Result) for every behavioural question. Three worked examples below.

---

Q: Tell me about a time you debugged a hard-to-reproduce distributed systems bug.

*Situation:* At my previous job I worked on a microservice that handled stateful session tracking for a telecom billing platform. We started seeing intermittent session drops that only appeared under sustained high load and were invisible in normal test runs.

*Task:* I needed to find and fix the root cause without being able to reproduce the bug reliably in a local test environment.

*Action:* I added structured tracing at every session state transition and deployed it to a staging environment that mirrored production traffic patterns. After running for several hours, I correlated timestamps across logs from two nodes and found that a race condition in the session handoff code was allowing a record to be deleted on one node before the other had confirmed receipt. I introduced a two-phase commit pattern for the handoff and wrote a targeted load test that could reproduce the failure reliably.

*Result:* The session drop rate went to zero in staging and held at zero after we deployed to production. The load test became part of the standard regression suite so the bug class cannot reappear silently.

---

Q: Describe a time you improved the performance of a system that was struggling under load.

*Situation:* A Go service I owned was responsible for aggregating interface statistics from network devices and forwarding them to a time-series database. As the number of monitored devices grew, the service began showing high tail latency and occasional timeouts during collection windows.

*Task:* I was asked to profile the service and reduce latency so that collection finished reliably within the scheduled window.

*Action:* I ran Go's built-in pprof profiler and found that the bulk of CPU time was spent in garbage collection triggered by many small short-lived allocations inside the collection loop. I refactored the hot path to reuse pre-allocated buffers from a sync.Pool, batched writes to the time-series database to reduce round-trip count, and added a backpressure mechanism so slow downstream writes could not cause unbounded queue growth.

*Result:* Tail latency dropped sharply and GC pause frequency fell as well. Collection windows completed reliably even as the device fleet continued to grow.

---

Q: Tell me about a time you had to collaborate closely with a hardware or platform team to solve a problem.

*Situation:* At a previous role, our software team was integrating a new line card into our routing platform. The card was showing unexpected forwarding errors that neither the software nor the hardware team could reproduce in isolation.

*Task:* I was the software engineer assigned to work with the hardware team to determine whether the issue was a firmware bug, a driver bug, or a protocol handling error in our stack.

*Action:* I set up a joint debugging session where we attached both software traces and hardware diagnostic counters to the same timeline. I wrote a small test harness that could inject specific traffic patterns while we read raw counter dumps from the line card. This let us narrow the failure to a specific interaction between our driver's interrupt coalescing settings and the card's DMA behaviour under burst traffic.

*Result:* The hardware team pushed a firmware fix and I updated the driver defaults. The forwarding errors disappeared. The joint debugging approach became our standard process for future card integrations.

STAR is the baseline for all behavioural questions: Situation (one or two sentences of context), Task (what you were responsible for), Action (what you specifically did, not what the team did), Result (a concrete outcome, even if you cannot share exact numbers).

For technical design questions, use a structured walkthrough: state your assumptions first, sketch the high-level components, explain data flow, then discuss trade-offs. DriveNets interviewers typically want to see you reason about failure modes and observability from the start, not as an afterthought.

For networking protocol questions, anchor your answer in the OSI model layer where the protocol operates, then explain the state machine or handshake, then move to failure modes and operational concerns. This signals that you think like a network engineer, not just a developer who has read the RFC.

For coding questions, think out loud about time and space complexity before writing a single line. DriveNets values engineers who can reason about performance implications in advance, which reflects their product's real-time packet-processing requirements.

DriveNets is building carrier-grade networking software that must handle very high packet rates with very low latency. This shapes exactly what interviewers are looking for.

Deep systems knowledge, not surface familiarity. They want engineers who can explain what happens at the kernel level, not just describe an API. If you say 'I used DPDK,' be ready to explain why kernel bypass matters and what the trade-offs are.

Protocol fluency. BGP, OSPF, MPLS, and segment routing come up regularly. Candidates who can speak to the operational behaviour of these protocols, not just their existence, stand out.

Performance-first thinking. Memory allocation patterns, cache locality, lock contention, and CPU affinity are fair game. Interviewers want to see that you consider these concerns before you are asked.

Ownership and clarity. In STAR answers, be specific about what *you* did versus what the team did. DriveNets looks for engineers who take clear ownership of hard problems.

Collaborative communication. Because their teams work across time zones and disciplines, candidates who explain their reasoning clearly and ask good clarifying questions score well even when they do not arrive at the perfect answer immediately.

Week 1: Networking foundations. Review BGP, OSPF, MPLS, and segment routing from an operational perspective, not just theory. Read about how disaggregated networking differs from traditional router architectures. DriveNets' public blog and technical whitepapers are a useful starting point.

Week 2: Systems programming. Refresh your knowledge of Linux networking internals: network namespaces, the kernel's packet processing path, eBPF and XDP basics, and DPDK fundamentals. For C++, revisit memory management patterns, lock-free data structures, and modern concurrency primitives.

Week 3: Distributed systems design. Practice designing high-availability control planes, streaming telemetry pipelines, and fault-tolerant state machines. Use the design question framework: assumptions first, then components, then data flow, then failure modes.

Week 4: Mock interviews and STAR practice. Write out STAR stories for five to eight significant projects you have worked on. Practice telling each story in under three minutes. Do at least two timed mock coding sessions focusing on systems-level problems.

While you prepare, knok checks 150+ job sites nightly, applies to jobs that match your resume, and messages HR on your behalf so you do not miss any of the 41 open DriveNets roles or new postings as they go live.

Treating networking as a secondary topic. Many candidates prepare heavily for coding exercises but arrive under-prepared on BGP or MPLS. At DriveNets, networking depth is often the deciding factor.

Vague STAR answers. Saying 'we improved performance' without describing what *you* did or what changed leaves interviewers with no signal. Specifics matter even when you cannot share exact figures.

Skipping failure modes in design questions. Candidates who design only the happy path consistently score lower. Always bring up what happens when a node fails, a link flaps, or a downstream service is slow.

Conflating user-space and kernel-space concepts. If you claim experience with DPDK or kernel bypass, expect a follow-up on why it matters. Shallow answers here can undercut an otherwise strong interview.

Not asking clarifying questions. DriveNets' problems often have ambiguous requirements by design. Diving straight into an answer without clarifying scope signals that you may do the same thing on the job.

Underselling cross-team collaboration. Because DriveNets teams span hardware, firmware, and software, candidates who can point to specific examples of working across disciplines are valued. Do not gloss over these stories.