Top 12 Voice Engineer Skills to Put on Your Resume

Telecom changes fast, and hiring managers skim even faster. A standout voice engineer resume blends hands-on protocol mastery with practical judgment under pressure—design, troubleshoot, secure, and explain. Put skills that map to real outcomes up front. Keep the fluff out. Make every bullet earn its keep.

Voice Engineer Skills

1. SIP (Session Initiation Protocol)
2. VoIP (Voice over Internet Protocol)
3. RTP (Real-time Transport Protocol)
4. Asterisk
5. Cisco Unified Communications
6. Avaya Systems
7. QoS (Quality of Service)
8. PBX (Private Branch Exchange)
9. SBC (Session Border Controller)
10. Wireshark (for packet analysis)
11. IVR (Interactive Voice Response)
12. Unified Communications

1. SIP (Session Initiation Protocol)

SIP is the signaling backbone for setting up, modifying, and tearing down real-time sessions—voice, video, messaging—across IP networks. It’s the handshake, the rules, the rendezvous point.

Why It's Important

SIP standardizes how calls get established and controlled across diverse systems. Interop gets simpler. Troubleshooting gets clearer. Scaling and securing services becomes repeatable instead of guesswork.

How to Improve SIP (Session Initiation Protocol) Skills

1. Harden signaling: Use TLS 1.2+ for SIP transport and SRTP for media. Enforce mutual TLS where possible. Rate-limit registrations and INVITEs. Block anonymous sources. Let your SBC do topology hiding and fraud detection.

2. Tune timers: Adjust Session-Expires/Min-SE for re-INVITEs, registration expiry for mobile users, and retransmission intervals in lossy segments. Nudge T1/T2 values only when you know the path behavior.

3. Choose sane codecs: G.711 for local high-fidelity paths, Opus for variable networks, G.729 where bandwidth is tight. Keep packetization at 20 ms by default; align across endpoints to curb transcoding.

4. Get trunks right: Match provider expectations on headers (P-Asserted-Identity, Diversion), early media, PRACK/100rel, and max concurrent sessions. Monitor 4xx/5xx patterns and SIP OPTIONS keepalives.

5. Plan for remote users: Solve NAT with SBC anchoring; for WebRTC, rely on ICE, STUN/TURN, and DTLS-SRTP. Don’t expose core SIP servers to the wild.

6. Observe relentlessly: Use call traces, SIP ladder diagrams, and synthetic call tests to spot drift early. Capture signaling with proper filtering; correlate to CDRs for root cause clarity.

Solid SIP hygiene prevents the 2 a.m. fire drills and keeps features from tripping over each other.

How to Display SIP (Session Initiation Protocol) Skills on Your Resume

2. VoIP (Voice over Internet Protocol)

VoIP converts voice to packets, ships them across IP, and stitches them back into clear conversation. Simple idea, unforgiving in practice.

Why It's Important

It slashes cost, rides existing networks, and unlocks features you can’t get on TDM. Scale it, instrument it, secure it—then it sings.

How to Improve VoIP (Voice over Internet Protocol) Skills

1. Engineer the LAN: Voice VLANs, LLDP-MED for QoS and power, PoE budgets that don’t brown out at boot storms, and switch queues that respect real-time traffic.

2. Chase the big three: Latency under 150 ms one-way, jitter under 30 ms, packet loss under 1%. If you miss these, no codec can rescue you.

3. Right-size bandwidth: Account for codec bitrate plus IP/UDP/RTP overhead and encryption. Factor call spikes, not just averages.

4. Stabilize endpoints: Keep firmware current. Standardize jitter buffers (adaptive is your friend). Enable echo control. Avoid gratuitous transcoding.

5. Instrument everything: Monitor MOS, RTCP/RTCP XR, and per-hop QoS markings. Run active probes from each site to the call core on a schedule.

6. Protect the edge: Use SBCs for trunking and remote workforces, segment management interfaces, and lock down provisioning servers.

How to Display VoIP (Voice over Internet Protocol) Skills on Your Resume

3. RTP (Real-time Transport Protocol)

RTP carries the media itself—voice and video—in real time. If SIP is traffic control, RTP is the convoy.

Why It's Important

Media must arrive on time, in order, without gaps. RTP and its sidekick RTCP keep that rhythm visible and manageable.

How to Improve RTP (Real-time Transport Protocol) Skills

1. Prioritize the payload: Mark RTP as DSCP EF (46). Keep packetization near 20 ms unless you’re fixing a specific problem. Avoid interleaving that adds delay.

2. Jitter buffers that adapt: Let endpoints and gateways adjust to network variance; fix them only when measurements justify it.

3. Minimize transcoding: Each hop that changes codec adds delay and risk. Standardize on a small codec set end to end.

4. Watch RTCP: Sender/receiver reports tell the truth—loss, jitter, round-trip time. Use it for alarm thresholds and trend detection.

5. Secure with SRTP: Encrypt media, enable authentication and replay protection. Use modern ciphers and perfect forward secrecy when possible.

How to Display RTP (Real-time Transport Protocol) Skills on Your Resume

4. Asterisk

Asterisk is the open-source telephony engine that powers DIY PBXs, IVRs, contact flows, and gateways. Flexible, scriptable, battle-tested.

Why It's Important

It lets you craft exactly what you need—call flows, integrations, automation—without waiting on vendor roadmaps. Low cost, high control.

How to Improve Asterisk Skills

1. Move to PJSIP: Prefer pjsip.conf over legacy sip.conf. You get better NAT handling, TLS/SRTP support, and modern features.

2. Design clean dialplans: Keep extensions.conf modular. Separate contexts for internal, external, and services. Use hints and device states sensibly.

3. Secure the box: Strong auth, IP allowlists, fail2ban, and separate signaling/media interfaces. Turn off modules you don’t use.

4. QoS and codecs: Standardize on Opus or G.711 where it fits. Limit transcoding. Mark DSCP appropriately on egress.

5. Monitor in depth: Enable verbose and SIP debug only for short bursts; rely on pcap captures and CDR/AMI/ARI data for ongoing visibility.

6. Scale smartly: Use call queues with sensible strategies, cache lookups, and offload media when possible. Hardware acceleration or DSP resources help when transcoding is unavoidable.

7. Stay current: Patch regularly. Asterisk evolves quickly, and security fixes arrive without fanfare.

How to Display Asterisk Skills on Your Resume

5. Cisco Unified Communications

A Cisco stack—CUCM, Unity, Expressway, CUBE, and the Webex ecosystem—brings voice, video, and messaging under one roof for on-prem, cloud, or hybrid deployments.

Why It's Important

It’s the enterprise workhorse. Scales to thousands, integrates with business apps, and supports complex dial plans and compliance needs with reliability.

How to Improve Cisco Unified Communications Skills

1. Architect for resiliency: Redundant CUCM clusters, CUBE HA, Expressway pairs, and SRST for branch survivability. Test failover paths, don’t assume.

2. Dial plan discipline: Normalize numbering, use partitions/CSS effectively, and document translation patterns. Keep emergency calling routes explicit and protected.

3. Modern security: SIP over TLS, SRTP, certificate management with automated renewal, and OAuth-based registration where supported. Lock down admin access and APIs.

4. Edge clarity: Treat CUBE as a B2BUA policy engine—header manipulation, codec control, overload protection, and STIR/SHAKEN attestation/verification.

5. Operational insight: Use RTMT, CDR/CMR analytics, and syslog streaming to a SIEM. Alert on registration churn, DSP exhaustion, and call failure spikes.

6. Keep current: Track firmware compatibility, device packs, and maintenance releases to avoid oddball crashes and interop surprises.

How to Display Cisco Unified Communications Skills on Your Resume

6. Avaya Systems

Avaya platforms—Aura Communication Manager and Session Manager, Avaya Experience Platform, and IP Office—anchor many large voice estates with deep contact center features.

Why It's Important

Enterprises rely on Avaya for uptime, sophisticated routing, and integrations with legacy and modern workflows. Knowing the stack keeps complex environments steady.

How to Improve Avaya Systems Skills

1. Standardize builds: Blueprint roles for CM, SM, SMGR, and SBC. Keep translations clean and version-controlled.

2. Tune survivability: Design for duplicated CM, geo-redundant Session Manager, and clear failback logic. Exercise the plan regularly.

3. Security posture: Enforce TLS/SRTP, narrow firewall pinholes, harden management interfaces, and audit for dormant accounts.

4. Diagnostics first: Use built-in traces and measurement servers. Trend signaling failures, trunk rejections, and vector step performance.

5. Integrate sanely: AES for CTI, stable SIP trunking to carriers, and policy at the SBC edge. Keep codec and early media settings consistent.

6. Lifecycle care: Patch on schedule, validate firmware, and align with supported compatibility matrices before upgrades.

How to Display Avaya Systems Skills on Your Resume

7. QoS (Quality of Service)

QoS is the traffic cop. It decides what gets fast-lane treatment when the pipes are crowded.

Why It's Important

Voice needs predictability. Without QoS, jitter and delay shred call quality the moment bandwidth gets tight.

How to Improve QoS (Quality of Service) Skills

1. Mark consistently: RTP as EF (46), SIP signaling as CS3. Video typically AF41. Keep markings intact end to end.

2. Queue with intent: Low-latency queues for voice, shape versus police on WAN links, and avoid bufferbloat. Validate with per-queue stats, not hunches.

3. Design for Wi‑Fi too: Map DSCP to WMM correctly. Ensure airtime fairness and capacity planning in dense areas.

4. Validate SLAs: Measure one-way delay, jitter, and loss per segment. Alarm when you cross thresholds, not after users complain.

5. Keep MTU honest: Mismatched MTU causes fragmentation and weird loss. Test the path, set it right.

How to Display QoS (Quality of Service) Skills on Your Resume

8. PBX (Private Branch Exchange)

A PBX orchestrates internal extensions, external trunks, and the features that tie them together—hunt groups, voicemail, conferencing, the works.

Why It's Important

It centralizes call control, trims costs, and enforces policy. For many businesses, it’s still mission control for voice.

How to Improve PBX (Private Branch Exchange) Skills

1. Modernize trunks: Migrate from PRI to SIP where feasible. Size sessions with headroom and confirm failover carriers ahead of time.

2. Dial plan guardrails: Normalize dialing, set class-of-service boundaries, and sandbox international dialing. Prevent toll fraud by design, not by cleanup.

3. Compliance matters: Ensure E911 meets current regulations (Kari’s Law and RAY BAUM’s Act in the U.S.) with correct dispatchable location and direct 911 access.

4. Resilience: Build survivable branches, backup power, and route diversity. Practice failovers like fire drills.

5. User enablement: Train admins and end users. Simple instructions and quick videos avert tickets later.

6. Integrate where it counts: Tie PBX events to CRM or service tools for screen pops and analytics, but keep the coupling loose and documented.

How to Display PBX (Private Branch Exchange) Skills on Your Resume

9. SBC (Session Border Controller)

An SBC secures, shapes, and translates sessions at network borders. Think doorman, translator, and traffic engineer in one box.

Why It's Important

It shields core systems, normalizes odd carrier behavior, and enforces policy. Without it, interop and security headaches multiply.

How to Improve SBC (Session Border Controller) Skills

1. Lock it down: TLS 1.2+ with modern ciphers, SRTP, access lists, and rate limits. Separate signaling from management. Turn on topology hiding.

2. Do caller ID right: Implement STIR/SHAKEN for attestation and verification to reduce spoofing and improve answer rates.

3. Normalize aggressively: Header manipulation, SIP diversion handling, SDP rewrites, and codec lists tailored per trunk.

4. Anchor media wisely: Keep RTP paths short and predictable. Transcode only when required and with sufficient DSP resources.

5. Plan capacity: Track sessions per second, total sessions, and media throughput. Size for spikes, not averages.

6. High availability: Active/standby or active/active with stateful failover. Test upgrade and rollback procedures.

How to Display SBC (Session Border Controller) Skills on Your Resume

10. Wireshark (for packet analysis)

Wireshark captures packets and lays them out so you can reconstruct what really happened, second by second, header by header.

Why It's Important

When logs disagree, the wire tells the truth. You’ll spot loss, jitter, mis-marked QoS, and malformed signaling without guesswork.

How to Improve Wireshark (for packet analysis) Skills

1. Filter like a pro: Master display filters for SIP, RTP, RTCP, TLS. Capture filters to keep files lean. Custom columns to surface call IDs, SSRCs, and DSCP at a glance.

2. Follow the flow: Use ladder views, Follow Stream, and coloring rules to separate multiple calls in noisy captures.

3. Decode media: Identify RTP streams, inspect jitter and loss, and use the RTP Player to listen when allowed. Provide audio snippets for evidence.

4. Time is everything: Sync to a reliable clock. Enable name resolution only when needed. Ring buffers prevent missed events on long runs.

5. Span with intent: Capture at the right hop—edge, core, or endpoint—so you see the problem, not just the aftermath.

How to Display Wireshark (for packet analysis) Skills on Your Resume

11. IVR (Interactive Voice Response)

IVR routes callers with prompts and inputs—DTMF or natural speech—so people reach answers or agents quickly.

Why It's Important

Done well, it trims wait times, boosts self-service, and cuts costs. Done poorly, it repels customers. The difference is design.

How to Improve IVR (Interactive Voice Response) Skills

1. Short, sharp menus: Keep choices tight. Two layers deep, max. Always offer “agent” or “say agent” escapes.

2. Conversational where it helps: Use speech recognition for open-ended intents; keep DTMF for account numbers and confirmations. Barge‑in to speed power users.

3. Smart callbacks: Virtual hold with accurate time estimates and reliable re-dial. Respect customer time zones and preferences.

4. Quality recordings: Consistent voice, proper pacing, clean audio levels. No robotic mixes that strain comprehension.

5. Iterate from data: Track containment rates, abandonment, and time-in-menu. Fix dead ends and confusing branches fast.

6. Accessibility and privacy: Support TTY/TDD where required, mask sensitive data in logs, and meet regional consent rules.

How to Display IVR (Interactive Voice Response) Skills on Your Resume

12. Unified Communications

UC blends voice, video, messaging, presence, and content sharing into one experience—often as UCaaS, sometimes hybrid with on‑prem call control.

Why It's Important

People work everywhere now. UC ties it together, keeps identity consistent, and streamlines collaboration without forcing users to juggle tools.

How to Improve Unified Communications Skills

1. Network first: Validate capacity and QoS before rollout. Segment real-time traffic. Plan for remote workers and mobile unpredictability.

2. Identity and security: Single sign‑on, MFA, conditional access. Encrypt signaling and media. Govern external federation deliberately.

3. PSTN interop: Use certified SBCs, direct routing equivalents, and resilient SIP trunks. Test emergency calling end to end.

4. Operational visibility: Call quality dashboards, synthetic probes, and per-user analytics. Close the loop with ticketing and alerting.

5. Change without chaos: Pilot features, document patterns, train champions. Roll out in waves with rollback plans ready.

How to Display Unified Communications Skills on Your Resume