> 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/adding-component-portion.md). # Adding component portion The **transaction component add** (request/response) message is used to add components to TCAP messages. Each invoked component must have a unique invoke identifier assigned within the current transaction. Upon receiving this request, TCAP builds the component in ASN.1 format and queues it until it gets the **transaction data send** message. The components are queued in the order in which they are added. The components that can be queued are limited to system memory. If any mandatory information is missing in the component structure (which is required to build the component) then an alarm or a reject component with **general encoding failure** problem code is generated (if the 'return on error' variable is set to 'True' as part of the general configuration). An invoke request can be canceled by sending a **transaction component add** message (for both ITU and ANSI TCAP) with component type set to component type 'unknown' and a cancellation flag of component structure set to 'True'. If the invoke component was not sent then it is to be removed from the queue and the instance of the invoke context will be deleted. If the invoke component was already sent and the instance of the invoke context exists then it would be deleted. In the case of ANSI TCAP, there is no invoke timer maintained in TCAP (the ANSI recommendation does not specify any timer). There is a possibility that a component is not received in response to an invoke component sent for operation class 2 (only failure is reported), 3 (only success is reported), and 4 (neither failure nor success is reported). The instance of the invoke context may remain allocated even after the operation is over. To resolve this situation, TCAP assumes that the TCAP user application maintains the operation timer, and upon expiry of this timer, application will generate a cancel request to TCAP (to delete the invoke instance). The component portion contains the following parameters: * TCAP userpart handle * TCAP transaction identifier * Component parameters * Component specific parameters buffer --- # 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/adding-component-portion.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.