> For the complete documentation index, see [llms.txt](https://prosbcdocs.telcobridges.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://prosbcdocs.telcobridges.com/telecom-references/protocols/mtp3-addressing.md). # MTP3 Addressing [MTP3](https://github.com/telcobridges-main/tmedia-wiki/tree/main/reference/protocols/mtp3/README.md) fully supports the use of addresses to identify [Signaling Points](https://github.com/telcobridges-main/tmedia-wiki/tree/main/reference/signalling/sp/README.md) (SPs). The following section describes signaling points in detail. ### Signaling points Signaling points are identified using [Destination Point Codes](https://github.com/telcobridges-main/tmedia-wiki/tree/main/reference/signalling/dpc/README.md) (DPCs). DPCs can be a number, up to 24 bits, based on the variant (for example, ITU has 14 bit DPC, ANSI has 24 bit DPC). In MTP3 software, each point code can be uniquely identified as a local SS7 point code or a remote SS7 point code. In MTP3 software, each signaling point is additionally identified by a network identifier (ID) which is unique to all signaling point codes within the network. This addressing is useful for simultaneously supporting multiple variants of MTP3 where each signaling point can be addressed by MTP3 using the combination of DPC and network ID. (**Note:** By virtue of the network ID, MTP3 can support the same DPC value for more than one signaling point if each of the signaling points that have the same DPC value belongs to a different network.) The Destination Point Code (DPC), [Origination Point Code](https://github.com/telcobridges-main/tmedia-wiki/tree/main/reference/signalling/opc/README.md) (OPC), and [Signaling Link Selection](https://github.com/telcobridges-main/tmedia-wiki/tree/main/reference/signalling/sls/README.md) (SLS) fields are part of the routing label in MTP3. The service indicator and network indicator are part of the Service Information Octet (SIO) of the MSU. The service indicator is four bits and can indicate an MTP service user or signaling network management service. The network indicator is two bits and can indicate a national or international network. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://prosbcdocs.telcobridges.com/telecom-references/protocols/mtp3-addressing.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.