TCP/IP Tutorial and Technical Overview - IBM Redbooks

The primitive types and their abbreviations are listed in Table 18-1.
Table 18-1 Service primitives
Type Abbreviation Description
Request req Used when a higher level requests a service from
a lower level.
Indication ind Used to notify the next higher layer of activities to
the peer (such as an invocation request) or to the
provider of the service (such as a protocol
generated event).
Response res A layer uses the response to acknowledge
receipt of indication from the next lower layer.
Confirm cnf The layer providing the requested service uses
confirm to report successfully completion of the
activity.
There are two primitives for the service layer:
T-DUnitdata Transmits data as datagram.
T-DError WDP can also receive a T-DError primitive if the requested
transmission cannot be executed by the WDP protocol layer.
Mapping WDP for IP
User Datagram Protocol (UDP), as a connection-less datagram service, is used
as the WDP protocol for any wireless bearer network where IP is used as a
routing protocol. UDP provides port-based addressing (destination and source
port). IP provides the segmentation and reassembly.
18.9.2 Wireless Profiled Transmission Control Protocol (WP-TCP)
One of the specifications newly introduced by the transport layer of the WAP2
architecture is a Wireless Profiled TCP (WP-TCP) used to provide
connection-oriented services. The implementation of WP-TCP is defined in the
OMA WAP-225-TCP-20010331-a specification. Benefits realized from this new
implementation include:
► Large data transfer
► End-to-end security
► Adherence to IETF protocols
Use of WP-TCP can use one of two approaches.
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