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Unit 12: Secure Application
protocol (WSP) layer offers a lightweight session layer to permit efficient exchange of data Notes
across applications.
Task What does denial of service protection mean? How is it accomplished in the WAP
architecture?
12.2.2 Comparison between WAP and Internet Protocol Layers
WAP architecture offers scalable and extensible environment for application development for
mobile communication devices. This is achieved through the layered design of the entire protocol
stack. Each of the layers of the architecture is accessible by the layers above, as well as by other
services and applications.
A pictorial comparison between WAP and the Internet Protocol Layers is given in Figure 12.6.
Figure 12.6
WAP Protocol Layers
Internet Protocol Layer
Browser/Application:WAE
Browser or Application
Session:WSP
Session/Transaction: HTTP
Transaction:WTP
Security:SSL/TLS
Security:WTLS
Transport: UDP/TCP
Datagram Transport WDP
Media
Bearers
The WAP layered architecture enables other services and applications to utilize the features of
the WAP stack through a set of well-defined interfaces. External applications may access the
session, transaction, and security and transport layers directly. The following sections provide
a description of the various elements of the protocol stack architecture. These layered applications
are symmetric; they reside both on the client device and the WAP Gateway. This layered structure
is very similar to the Internet Protocol Stack.
Bearers
The WAP protocols are modeled to operate over a variety of bearer services, including short
message, circuit-switching data and packet data. The bearers offer differing levels of quality of
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