Telefonia como biblioteca, não como aluguel.

using Verbara.Sdk.Ari;
using Verbara.Sdk.Activities;

var ari = new AriClient("http://pbx:8088", "verbara", "secret");

// Place outbound call to a customer.
var outbound = await ari.Channels.OriginateAsync(
  endpoint: "PJSIP/+15551234567@telco-trunk",
  extension: "outbound",
  context: "default");

// Connect them to an agent on a separate channel + record.
var agent = await ari.Channels.OriginateAsync(
  endpoint: "PJSIP/agent101@internal",
  extension: "agent",
  context: "internal");

var bridge = await ari.Bridges.CreateAsync(type: "mixing");
await ari.Bridges.AddChannelAsync(bridge.Id, outbound.Id);
await ari.Bridges.AddChannelAsync(bridge.Id, agent.Id);

var recording = await ari.Channels.RecordAsync(
  outbound.Id,
  name: $"call-{outbound.Id}",
  format: "wav");