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Path and Service-Route

Path is the inbound vector stored with a binding, and Service-Route is the outbound vector the registrar gives the UA.

Learn in 5 minutes

  1. Insert Path on REGISTER the way a proxy inserts Record-Route
  2. Use Service-Route as a preloaded Route for a new request
  3. Keep the two vectors from being swapped

Visual

Learn both vectors, then call · study drawing · cyphermonkeylabs.com UAEdgeRegistrar REGISTER REGISTER 200 INVITE

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Both headers look like Route URIs. They are learned at registration and they point in opposite directions.

Worked example

Which header is outbound? The 200 OK has both Path and Service-Route. Pick the one the UA will preload.

  1. Dissect the 200.
  2. Read Path.
  3. Read Service-Route.

Fault

The binding exists, and the INVITE for the UA is sent straight to 203.0.113.10. The edge that inserted Path never sees it, and the NAT binding is dead.

The Contact address was reachable only through the edge that registered it.

Quiz

Path is defined in


Service-Route is used by the UA as


The registrar stores Path


Path and Record-Route differ because


Supported: path means


Swapping Path and Service-Route


Ecosystem

Glossary, sister systems, and the integration seam for this room.

CRM Screen pop uses data the contact center already has: ANI, DNIS, case id. Those values may arrive in SIP headers or in a CTI event after the call is up. The CRM is not a SIP element.

Glossary · Ecosystem map · Ports · Troubleshooting

Sources and go deeper