
Protecting the intellectual property of natural language encoders faces a critical challenge: hidden watermarks are easy to be erased when models are fine-tuned to adapt to downstream applications, known as “task migration”. To deal with this problem, we introduce a Task Migration Resistant Watermarking (TMRW) framework to strengthen the watermark robustness against task migration. The proposed method uses a dual-objective fine-tuning strategy. During the process of watermark embedding, a specifically designed watermark loss function is introduced to compel the encoder to map a set of trigger inputs into a compact cluster in the embedding space. To counteract the potential performance degradation introduced by this process, an augmented contrastive loss is simultaneously optimized to preserve the encoder’s general semantic representation abilities. This dual-objective strategy is further enhanced by a novel trigger corpus crafting method that ensures the watermark’s stealthiness. Experimental results show that the proposed method enables the embedding of a robust watermark that significantly outperforms existing techniques in resisting erasure from task migration. This work well deals with the challenge of encoder watermark’s durability against task migration, which provides a novel and practical framework for intellectual property protection in natural language processing systems.

Chatbots are computer programs that execute protocols for supporting human-machine conversations and perform various functions such as searching the web, ordering food, making appointments, and many more. To facilitate timely responses and actions, and enable interactive human-like conversations, chatbots require Natural Language Processing (NLP) to understand user's messages and respond appropriately. NLP is an area of computer science and artificial intelligence concerned with the interactions between computers and human languages. Google Dialogflow is a natural language understanding platform that makes it easy to design and integrate a conversational user interface into your mobile app, web application, device, bot, interactive voice response system, and so on. Dash Messaging is a smart chatbot platform that enables creation of chatbots based on the provided protocol for long-term conversations. In this paper, we discuss how to integrate Google Dialogflow NLP service to a case study chatbot launched with our Dash Messaging platform.