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Topology hiding rewrites the addresses you leak

Topology hiding replaces caller addresses in signaling and, when media is anchored, in SDP.

Learn in 5 minutes

  1. Name the headers that leak topology
  2. See Contact and Via change at the B2BUA
  3. Leave the rewrite policy in the product guide

Visual

Hide the caller address · study drawing · cyphermonkeylabs.com AliceSBCCarrier INVITE 100 INVITE 180

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Addresses below are the lab’s documentation addresses.

Worked example

Compare Contact hosts Dissect the carrier INVITE. Which host is in Contact?

    Fault

    The carrier INVITE still targets the dialog at 203.0.113.10, which is not routed on the carrier side.

    Both Contact and c= still say 203.0.113.10.

    Quiz

    Topology hiding is aimed at


    On the carrier INVITE in this lesson, Contact is


    A pure proxy would typically


    When media is anchored, SDP c= on the outside leg names


    User-Agent on the carrier INVITE in this synthetic is


    The list of headers a given SBC strips is found in


    Ecosystem

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

    E911 / emergency calling Location has to ride with the call. RFC 6881 is the BCP, RFC 6442 carries location in SIP, and the FCC MLTS page states Kari’s Law and RAY BAUM’s Act obligations for multi-line systems.

    Glossary · Ecosystem map · Ports · Troubleshooting

    Sources and go deeper