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SIP termination for outbound voice

Wholesale SIP termination is outbound calling to any destination, bought in volume over a SIP interconnect and billed per destination. Callivex delivers it on direct EU carrier interconnects, for VoIP carriers and ITSPs, CPaaS and AI voice platforms, cloud PBX operators, white-label resellers, enterprises, small businesses and contact centers, from a single trunk to carrier-scale interconnects.

Clear CLI, end-to-end

Your calling-line identity passes intact from your SBC to the destination network - never stripped, never substituted. Higher answer rates on EU and North American termination.

Stable routes

Direct carrier interconnects with consistent quality, so the ASR you test with is the ASR you run with.

Quality you can measure

ASR and PDD monitored per destination in real time, with ASR-weighted carrier failover. Degrading routes are pulled before your campaigns feel it.

Capacity sized to your traffic

Whether you run a ten-seat office or a large dialer operation, your account is sized for the traffic you actually run, with capacity sized to your peaks, burstable on request.

  • Capacity sized to your traffic, burstable on review
  • Per-account simultaneous-channel caps enforced at SBC layer
  • Contact-center traffic patterns are supported
  • Codec negotiation: G.711 a-law and u-law, G.729, G.722, Opus
  • SIP REFER for blind and attended transfer; early media supported
  • Carrier-side disconnect codes propagated upstream (480, 486, 503 mapped properly)
# SBC profile - 500 channels Account: contact_center_a Channel cap: 500 simultaneous Auth: IP whitelist (3 source IPs) Codecs: PCMA, G729, opus Disconnect: Q.850 cause-code propagation CLI policy: clear CLI, passed end-to-end Routing: LCR - quality, then cost Failover: 3 carriers, ASR-weighted
# Per-second CDR - sample CDR-Id: 5f9c1a... From: +442077000123 To: +33122334455 Setup: 2026-05-06 14:32:09 UTC Answer: 2026-05-06 14:32:14 UTC End: 2026-05-06 14:33:47 UTC Duration: 93 sec (billed per second) Destination: FR · Mobile (Orange) Rate: €0.04200 / min Cost: €0.06510 Disposition: answered (NORMAL_CLEARING)

Per-second billing, not per-minute rounded up

Every second of every connected call is rated. Five-decimal precision keeps long-tail destinations economic. Real-time CDR streaming so your platform can react inside seconds - not at end-of-day.

  • Per-second billing on all destinations (no minimum-duration rounding)
  • Five-decimal rate precision (€0.00001/min granularity)
  • Real-time CDR webhook + JSON API; CSV export available
  • Prepaid balance with hard cut-off on every account
  • Per-customer rate sheets supported (volume tiers, dedicated routes)
  • Daily reconciled invoicing in EUR, USD, or GBP

LCR with ASR-weighted failover

Routes aren't ordered by price. Each destination has a primary, a backup, and a fallback, weighted by recent answer-seizure ratio (ASR) and post-dial delay (PDD). When a route's quality drops, traffic shifts within minutes, not at the next quarterly review.

  • Multi-carrier LCR per destination, ranked by quality and cost
  • ASR and PDD windowed over 15-minute and 1-hour intervals
  • Auto-fallback on carrier 5xx, timeout, or PDD spike
  • Customer-visible per-route stats inside the portal
  • SLA-backed availability targets - see the SLA
# LCR table - DE · Landline (49) ASR PDD Rate Pri carrier_a (EU) 62% 1.8s €0.0042 primary carrier_b (DE) 58% 2.0s €0.0048 backup carrier_c (NL) 54% 2.3s €0.0061 fallback # Last 15 min - 412 attempts, 38% answered # Failover: 3 attempts auto-shifted to carrier_b

Acceptance & onboarding

Wholesale termination is a regulated service. Onboarding is intentional, not instant.

  1. Account review. We confirm your company details and traffic profile before issuing credentials. All accounts run prepaid.
  2. Test trunk. A test sub-account with starter credit is provisioned within one business day of approval. You verify codec negotiation, CDR delivery, and disconnect-code mapping.
  3. Production cut-over. Channel and call-rate limits are sized to your forecast, your IP whitelist is locked in, and your account moves to your chosen rate plan.
  4. Ongoing. Quality dashboards, monthly invoice reconciliation, and a named contact for escalations. Carriers change; routes change. We re-baseline routing quarterly.

Ready for wholesale termination?

Tell us your destination mix and forecast traffic. Quotes typically come back within 24 hours.

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