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Changes for page SIP

Last modified by Aaron Blackburn on 2026/09/01 19:00
From version 1.4
edited by Aaron Blackburn
on 2026/09/01 19:00
Change comment: There is no comment for this version
To version 1.1
edited by Aaron Blackburn
on 2026/07/22 20:53
Change comment: There is no comment for this version

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Page properties
Content
... ... @@ -1,438 +1,0 @@
1 -{{html clean="false"}}
2 -<!--
3 - XWiki usage: Paste into an HTML macro on your page.
4 - Note: All FirstDigital public IPs have been sanitized for public wiki security.
5 --->
6 -<style>
7 - @import url('https://fonts.googleapis.com/css2?family=Host+Grotesk:wght@300;400;500;600;700;800&display=swap');
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31 -
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142 -
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168 -
169 - /* Troubleshooting Table */
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192 -
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195 - }
196 -</style>
197 -
198 -<div class="fd-sip-doc">
199 -
200 - <!-- Header Banner -->
201 - <div class="doc-header">
202 - <p class="kicker">FirstDigital Voice Operations</p>
203 - <h1>SIP Trunking Technical Reference</h1>
204 - <p class="sub">Network architecture, firewall requirements, and troubleshooting standards for customer SIP trunks.</p>
205 - </div>
206 -
207 - <!-- Disclaimer Notice -->
208 - <div class="disclaimer-box">
209 - <strong>Customer Responsibility Notice:</strong> Customers are responsible for the configuration and maintenance of their own routers, firewalls, and PBX equipment. FirstDigital provides these specifications to assist engineers during trunk integration.
210 - </div>
211 -
212 - <!-- DIAGRAM 1: Network Topology -->
213 - <div class="section-title">1. SIP Trunk Topology & Traffic Routing</div>
214 - <div class="diagram-card">
215 - <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 800 300" style="font-family:'Host Grotesk', system-ui, sans-serif;">
216 - <!-- Cloud Node -->
217 - <rect x="30" y="50" width="200" height="200" rx="12" fill="#f0f7fc" stroke="#307ab2" stroke-width="2"/>
218 - <rect x="45" y="35" width="170" height="26" rx="13" fill="#003366"/>
219 - <text x="130" y="52" fill="#ffffff" font-size="11" font-weight="bold" text-anchor="middle">FIRSTDIGITAL CLOUD</text>
220 - <text x="130" y="115" fill="#003366" font-size="14" font-weight="bold" text-anchor="middle">FirstDigital SBC</text>
221 - <rect x="55" y="130" width="150" height="24" rx="4" fill="#e2e8f0"/>
222 - <text x="130" y="146" fill="#2e404d" font-size="11" font-family="monospace" text-anchor="middle">[FirstDigital_SBC_IP]</text>
223 - <text x="130" y="180" fill="#2e404d" font-size="10" text-anchor="middle">Signaling &amp; Audio Target</text>
224 -
225 - <!-- Flow Connectors -->
226 - <path d="M 230 110 L 370 110" stroke="#307ab2" stroke-width="3" stroke-dasharray="6,4"/>
227 - <path d="M 370 160 L 230 160" stroke="#38b2e3" stroke-width="3"/>
228 - <polygon points="230,160 238,155 238,165" fill="#38b2e3"/>
229 - <polygon points="370,110 362,105 362,115" fill="#307ab2"/>
230 - <text x="300" y="100" fill="#003366" font-size="10" font-weight="bold" text-anchor="middle">UDP 5060 (SIP)</text>
231 - <text x="300" y="180" fill="#003366" font-size="10" font-weight="bold" text-anchor="middle">UDP 5k-65k (RTP)</text>
232 -
233 - <!-- Firewall Node -->
234 - <rect x="370" y="50" width="180" height="200" rx="12" fill="#fff5f5" stroke="#cf333d" stroke-width="2"/>
235 - <rect x="385" y="35" width="150" height="26" rx="13" fill="#cf333d"/>
236 - <text x="460" y="52" fill="#ffffff" font-size="11" font-weight="bold" text-anchor="middle">CUSTOMER FIREWALL</text>
237 - <text x="460" y="105" fill="#003366" font-size="13" font-weight="bold" text-anchor="middle">Public Edge Router</text>
238 - <rect x="385" y="120" width="150" height="24" rx="4" fill="#e2e8f0"/>
239 - <text x="460" y="136" fill="#2e404d" font-size="11" font-family="monospace" text-anchor="middle">[Customer_Public_IP]</text>
240 - <text x="460" y="175" fill="#cf333d" font-size="10" font-weight="bold" text-anchor="middle">SIP ALG: DISABLED</text>
241 - <text x="460" y="195" fill="#2e404d" font-size="10" text-anchor="middle">Source NAT Active</text>
242 -
243 - <!-- Internal LAN Path -->
244 - <path d="M 550 135 L 610 135" stroke="#2e404d" stroke-width="2"/>
245 -
246 - <!-- PBX Node -->
247 - <rect x="610" y="50" width="160" height="200" rx="12" fill="#f8fafc" stroke="#003366" stroke-width="2"/>
248 - <rect x="625" y="35" width="130" height="26" rx="13" fill="#003366"/>
249 - <text x="690" y="52" fill="#ffffff" font-size="11" font-weight="bold" text-anchor="middle">CUSTOMER PBX</text>
250 - <text x="690" y="115" fill="#003366" font-size="13" font-weight="bold" text-anchor="middle">Internal PBX / SBC</text>
251 - <rect x="625" y="130" width="130" height="24" rx="4" fill="#e2e8f0"/>
252 - <text x="690" y="146" fill="#2e404d" font-size="11" font-family="monospace" text-anchor="middle">192.168.x.x (LAN)</text>
253 - </svg>
254 - <div class="diagram-caption">Figure 1: Standard end-to-end SIP signaling and RTP media pathing via customer firewall.</div>
255 - </div>
256 -
257 - <!-- Specifications Grid -->
258 - <div class="section-title">2. Core Trunk Parameters</div>
259 - <div class="specs-grid">
260 - <div class="spec-card">
261 - <div class="label">Signaling Protocol</div>
262 - <div class="val">UDP 5060</div>
263 - <div class="subtext">Standard SIP port</div>
264 - </div>
265 - <div class="spec-card">
266 - <div class="label">Primary Codec</div>
267 - <div class="val">G.711u</div>
268 - <div class="subtext">20ms packetization</div>
269 - </div>
270 - <div class="spec-card">
271 - <div class="label">DTMF Mode</div>
272 - <div class="val">RFC 2833</div>
273 - <div class="subtext">Out-of-band touch tones</div>
274 - </div>
275 - <div class="spec-card">
276 - <div class="label">DNIS Delivery</div>
277 - <div class="val">10 Digits</div>
278 - <div class="subtext">+1 stripped; Intl disabled by default</div>
279 - </div>
280 - <div class="spec-card">
281 - <div class="label">Authentication</div>
282 - <div class="val">IP Registration-less</div>
283 - <div class="subtext">No user/password required</div>
284 - </div>
285 - <div class="spec-card">
286 - <div class="label">SIP Advanced</div>
287 - <div class="val">Peer Path / Re-invite</div>
288 - <div class="subtext">Disabled / No re-invites permitted</div>
289 - </div>
290 - </div>
291 -
292 - <!-- DIAGRAM 2: REWORKED FIREWALL PACKET FILTER & PORT MAP ILLUSTRATION -->
293 - <div class="section-title">3. Firewall Policy Rules & Packet Filter Action</div>
294 - <div class="diagram-card">
295 - <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 800 290" style="font-family:'Host Grotesk', system-ui, sans-serif;">
296 - <!-- Outer Frame -->
297 - <rect x="10" y="10" width="780" height="270" rx="12" fill="#f8fafc" stroke="#e2e8f0" stroke-width="2"/>
298 -
299 - <!-- FirstDigital WAN Side -->
300 - <text x="110" y="40" fill="#003366" font-size="12" font-weight="bold" text-anchor="middle">WAN SOURCE</text>
301 - <text x="110" y="58" fill="#2e404d" font-size="11" font-family="monospace" text-anchor="middle">[FirstDigital_Subnet]</text>
302 -
303 - <!-- Firewall Barrier (Middle) -->
304 - <rect x="360" y="30" width="80" height="230" rx="8" fill="#fff5f5" stroke="#cf333d" stroke-width="2"/>
305 - <text x="400" y="135" fill="#cf333d" font-size="12" font-weight="bold" text-anchor="middle" transform="rotate(-90,400,135)">FIREWALL BOUNDARY</text>
306 -
307 - <!-- Customer LAN Side -->
308 - <text x="690" y="40" fill="#003366" font-size="12" font-weight="bold" text-anchor="middle">LAN DESTINATION</text>
309 - <text x="690" y="58" fill="#2e404d" font-size="11" font-family="monospace" text-anchor="middle">[Customer_PBX_IP]</text>
310 -
311 - <!-- ROW 1: SIP SIGNALING (PASS) -->
312 - <path d="M 200 90 L 360 90" stroke="#2e7d32" stroke-width="2.5"/>
313 - <circle cx="380" cy="90" r="10" fill="#2e7d32"/>
314 - <text x="380" y="94" fill="#ffffff" font-size="11" font-weight="bold" text-anchor="middle">✓</text>
315 - <path d="M 400 90 L 580 90" stroke="#2e7d32" stroke-width="2.5"/>
316 - <polygon points="580,90 572,85 572,95" fill="#2e7d32"/>
317 -
318 - <rect x="220" y="72" width="120" height="22" rx="4" fill="#e8f5e9" stroke="#2e7d32"/>
319 - <text x="280" y="87" fill="#2e7d32" font-size="10" font-weight="bold" text-anchor="middle">SIP: UDP 5060</text>
320 - <text x="480" y="82" fill="#2e7d32" font-size="10" font-weight="bold" text-anchor="middle">FORWARD TO PBX</text>
321 -
322 - <!-- ROW 2: RTP AUDIO STREAM (PASS) -->
323 - <path d="M 200 150 L 360 150" stroke="#307ab2" stroke-width="2.5"/>
324 - <circle cx="380" cy="150" r="10" fill="#2e7d32"/>
325 - <text x="380" y="154" fill="#ffffff" font-size="11" font-weight="bold" text-anchor="middle">✓</text>
326 - <path d="M 400 150 L 580 150" stroke="#307ab2" stroke-width="2.5"/>
327 - <polygon points="580,150 572,145 572,155" fill="#307ab2"/>
328 -
329 - <rect x="210" y="132" width="140" height="22" rx="4" fill="#f0f7fc" stroke="#307ab2"/>
330 - <text x="280" y="147" fill="#003366" font-size="10" font-weight="bold" text-anchor="middle">RTP: UDP 5k - 65k</text>
331 - <text x="480" y="142" fill="#003366" font-size="10" font-weight="bold" text-anchor="middle">ALLOW MEDIA STREAM</text>
332 -
333 - <!-- ROW 3: SIP ALG / INSPECTION (BLOCKED) -->
334 - <path d="M 200 215 L 360 215" stroke="#cf333d" stroke-width="2.5" stroke-dasharray="4,4"/>
335 - <circle cx="380" cy="215" r="10" fill="#cf333d"/>
336 - <text x="380" y="219" fill="#ffffff" font-size="11" font-weight="bold" text-anchor="middle">✕</text>
337 -
338 - <rect x="220" y="197" width="120" height="22" rx="4" fill="#fff5f5" stroke="#cf333d"/>
339 - <text x="280" y="212" fill="#cf333d" font-size="10" font-weight="bold" text-anchor="middle">SIP ALG / STUN</text>
340 - <text x="485" y="212" fill="#cf333d" font-size="11" font-weight="bold">DISABLED (Prevents Header Modification)</text>
341 -
342 - <!-- Bottom Note -->
343 - <rect x="180" y="250" width="440" height="20" rx="4" fill="#e2e8f0"/>
344 - <text x="400" y="264" fill="#2e404d" font-size="10" font-weight="bold" text-anchor="middle">OUTBOUND EGRESS NAT: All traffic MUST egress sourcing from [Customer_Public_IP]</text>
345 - </svg>
346 - <div class="diagram-caption">Figure 2: Firewall packet-filtering policy—explicitly allowing signaling/media while disabling SIP ALG.</div>
347 - </div>
348 -
349 - <!-- Rules Text -->
350 - <div class="rules-grid">
351 - <div class="rule-box">
352 - <h4>Outbound Traffic Requirements</h4>
353 - <ul>
354 - <li>Outbound calls to FirstDigital must source directly from the registered Customer Public IP.</li>
355 - <li>Outbound calls must send Caller ID matching a phone number assigned to the trunk instance.</li>
356 - <li>FirstDigital will automatically reject calls sourcing from unknown or unauthorized IPs.</li>
357 - </ul>
358 - </div>
359 - <div class="rule-box">
360 - <h4>Firewall & NAT Settings</h4>
361 - <ul>
362 - <li><strong>SIP ALG:</strong> Must be completely <u>DISABLED</u> on customer edge firewalls and routers.</li>
363 - <li><strong>RTP Media:</strong> Ensure UDP ports 5000-65000 are permitted for full audio stream delivery.</li>
364 - <li><strong>NAT Routing:</strong> Confirm outbound NAT egress explicitly maps internal PBX traffic to the registered public IP.</li>
365 - </ul>
366 - </div>
367 - </div>
368 -
369 - <!-- DIAGRAM 3: One-Way Audio Problem -->
370 - <div class="section-title">4. Common Audio Defect: Private IP Header Leakage</div>
371 - <div class="diagram-card">
372 - <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 800 240" style="font-family:'Host Grotesk', system-ui, sans-serif;">
373 - <!-- SBC Box -->
374 - <rect x="40" y="40" width="180" height="160" rx="10" fill="#f0f7fc" stroke="#307ab2" stroke-width="2"/>
375 - <text x="130" y="80" fill="#003366" font-size="13" font-weight="bold" text-anchor="middle">FirstDigital SBC</text>
376 - <text x="130" y="100" fill="#2e404d" font-size="10" text-anchor="middle">Public Media Gateway</text>
377 -
378 - <!-- Broken Return Audio Path -->
379 - <path d="M 220 160 L 410 160" stroke="#cf333d" stroke-width="3" stroke-dasharray="4,4"/>
380 - <circle cx="420" cy="160" r="12" fill="#cf333d"/>
381 - <text x="420" y="165" fill="#ffffff" font-size="13" font-weight="bold" text-anchor="middle">X</text>
382 - <text x="315" y="150" fill="#cf333d" font-size="10" font-weight="bold" text-anchor="middle">Audio Fails: 192.168.x.x Unreachable</text>
383 -
384 - <!-- Firewall Box -->
385 - <rect x="450" y="40" width="120" height="160" rx="10" fill="#fff5f5" stroke="#cf333d" stroke-width="2"/>
386 - <text x="510" y="120" fill="#cf333d" font-size="12" font-weight="bold" text-anchor="middle">Firewall</text>
387 -
388 - <!-- PBX Box -->
389 - <rect x="620" y="40" width="140" height="160" rx="10" fill="#f8fafc" stroke="#003366" stroke-width="2"/>
390 - <text x="690" y="75" fill="#003366" font-size="13" font-weight="bold" text-anchor="middle">Customer PBX</text>
391 -
392 - <!-- Problem Header Packet -->
393 - <path d="M 620 85 L 230 85" stroke="#307ab2" stroke-width="2"/>
394 - <rect x="310" y="60" width="240" height="24" rx="4" fill="#fffbe0" stroke="#d97706"/>
395 - <text x="430" y="76" fill="#b45309" font-size="10" font-weight="bold" text-anchor="middle">SDP Header: Audio IP = 192.168.1.50 (Private IP Leak!)</text>
396 - </svg>
397 - <div class="diagram-caption">Figure 3: Why one-way audio occurs—the PBX requests return audio to an unreachable internal private IP address.</div>
398 - </div>
399 -
400 - <!-- Troubleshooting Matrix -->
401 - <div class="section-title">5. Troubleshooting Matrix</div>
402 - <table class="tb-table">
403 - <thead>
404 - <tr>
405 - <th>Symptom</th>
406 - <th>Root Cause & Resolution Step</th>
407 - </tr>
408 - </thead>
409 - <tbody>
410 - <tr>
411 - <td class="symptom">No Inbound Calls</td>
412 - <td>Verify firewall allows <code>UDP 5060</code> from FirstDigital's subnet. Confirm <strong>SIP ALG is disabled</strong> on edge devices.</td>
413 - </tr>
414 - <tr>
415 - <td class="symptom">No Outbound Calls</td>
416 - <td>Confirm outbound SIP traffic is directed to FirstDigital's SBC IP on <code>UDP 5060</code>. Verify traffic sources from your registered Public IP and uses an assigned Caller ID.</td>
417 - </tr>
418 - <tr>
419 - <td class="symptom">One-Way or No Audio</td>
420 - <td><strong>Common Issue:</strong> PBX is leaking private IP addresses (e.g., <code>10.x.x.x</code> or <code>192.168.x.x</code>) in the SIP SDP header. Fix PBX NAT settings, SBC Media Address Override, or STUN configuration. Disable SIP ALG.</td>
421 - </tr>
422 - <tr>
423 - <td class="symptom">Touch Tones Not Working</td>
424 - <td>Configure PBX and endpoints to send DTMF out-of-band using <strong>RFC 2833</strong> (telephony-event).</td>
425 - </tr>
426 - <tr>
427 - <td class="symptom">Calls Routing Incorrectly</td>
428 - <td>Inspect received <strong>DNIS digit delivery</strong>. FirstDigital defaults to 10-digit delivery. Update PBX inbound routing rules to match.</td>
429 - </tr>
430 - <tr>
431 - <td class="symptom">Forwarded Calls Have One-Way Audio</td>
432 - <td>Occurs if FirstDigital enabled "NAT Media" as a temporary workaround for private IP header leaks. Resolving the PBX private IP leak allows FirstDigital to disable NAT Media settings, resolving transfer audio.</td>
433 - </tr>
434 - </tbody>
435 - </table>
436 -
437 -</div>
438 -{{/html}}