IP-Based Voice Connectivity

SIP trunking înlocuiește liniile telefonice tradiționale cu conexiuni IP, oferind scalabilitate, flexibilitate, și costuri reduse pentru voice AI.

SIP Trunk Architecture

PSTN

Traditional Phone Network

SIP Trunk

IP-Based Connection

Voice AI

Your Platform

Caller → PSTN → Carrier SBC → SIP INVITE →

→ Your SBC → Voice AI Platform

Trunk Configuration

// Example SIP Trunk Config
{
  "trunk_name": "primary-carrier",
  "carrier": "twilio",
  "endpoints": [
    {
      "host": "sip.twilio.com",
      "port": 5060,
      "transport": "UDP",
      "priority": 1
    },
    {
      "host": "sip-backup.twilio.com",
      "port": 5060,
      "transport": "UDP",
      "priority": 2
    }
  ],
  "authentication": {
    "type": "ip_acl",
    "allowed_ips": ["54.172.60.0/24"]
  },
  "codecs": ["PCMU", "PCMA", "opus"],
  "max_channels": 100,
  "failover_trunk": "backup-carrier"
}

Carrier Options

Carrier	Global Reach	Pricing	Best For
Twilio	180+ countries	$0.0085/min	Developer-friendly
Vonage	160+ countries	$0.0070/min	Enterprise features
Bandwidth	US/Canada	$0.0050/min	Cost efficiency
Telnyx	140+ countries	$0.0060/min	Low latency

Channel Capacity Planning

Current Usage

Peak Concurrent Calls72

Trunk Capacity100 channels

Headroom: 28 channels (28%)

Capacity Formula

Channels = Peak_Calls × 1.3

Current: 72 × 1.3 = 94

Recommendation: 100 channels ✓

Codec Negotiation

G.711 (PCMU/PCMA)

• Bandwidth: 64 kbps
• Latency: Very low
• Quality: Good
• Best: PSTN compatibility

Opus

• Bandwidth: 6-510 kbps
• Latency: Low
• Quality: Excellent
• Best: WebRTC, quality

G.729

• Bandwidth: 8 kbps
• Latency: Medium
• Quality: Acceptable
• Best: Bandwidth savings

m=audio 49170 RTP/AVP 0 8 96

a=rtpmap:0 PCMU/8000

a=rtpmap:8 PCMA/8000

a=rtpmap:96 opus/48000/2

Failover Configuration

Primary Trunk

Twilio - sip.twilio.com (Priority 1)

Active

Secondary Trunk

Vonage - sip.vonage.com (Priority 2)

Standby

Tertiary Trunk

Bandwidth - sip.bandwidth.com (Priority 3)

Standby

Failover triggers: 503 Service Unavailable, 408 Timeout, network unreachable

Authentication Methods

IP ACL (Recommended)

Whitelist carrier IP ranges. No credentials in SIP messages.

allow 54.172.60.0/24

allow 54.244.51.0/24

deny all

Digest Authentication

Username/password challenge-response. More flexible but adds latency.

username: "trunk_user"

password: "••••••••"

realm: "sip.carrier.com"

Cost Optimization

Least Cost Routing

Route calls through cheapest carrier based on destination.

Commitment Plans

Pre-pay minutes for 20-40% discount vs pay-as-you-go.

Codec Optimization

Use G.729 for long-distance to reduce bandwidth costs.

Scalable Voice Connectivity

SIP trunking pentru voice AI la scară enterprise.

Vezi Demo →

SIP Trunking