Wireless transaction protocol (WTP) manages transactions by conveying requests and responses between a user agent and an application server for such activities as browsing and e-commerce transactions. WTP provides a reliable transport service but dispenses with much of the overhead of TCP, resulting in a lightweight protocol that is suitable for implementation in "thin" clients (e.g., mobile nodes) and suitable for use over low-bandwidth wireless links.

WTP includes the following features:

• Three classes of transaction service.

• Optional user-to-user reliability: WTP user triggers the confirmation of each received message.

• Optional out-of-band data on acknowledgments.

• PDU concatenation and delayed acknowledgment to reduce the number of messages sent.

• Asynchronous transactions.

WTP is transaction oriented rather than connection oriented. With WTP, there is no explicit connection setup or teardown but rather a reliable connectionless service.