Stateless SIP Implementation

A Stateless SIP Stack processes each SIP request and response independently, without tracking session state. It does not retain transaction or dialog information, making it fast and memory-efficient but less reliable for tracking ongoing communications. Stateless processing is ideal for high-throughput SIP proxies that forward messages without maintaining context.

How Stateless SIP Operates

Every SIP request (e.g., INVITE, BYE, REGISTER, OPTIONS) is treated as a standalone event, with no memory of previous interactions. That means that the system does not track call progress, transactions, or session states. Consequently, there is no storage of transaction state - once a request is processed, it is immediately discarded, reducing memory consumption. Stateless SIP does not retain any information about request-response pairs, nor does it store sequence numbers, retransmission timers, or dialog states. When a response (e.g., 200 OK, 486 Busy Here) is generated, it is based only on the received request without reference to prior messages. The system does not check for retransmissions or previously processed requests, so if an INVITE request is sent twice due to packet loss, a Stateless SIP element will treat both as entirely new requests, potentially leading to duplicate processing.