The center of the simulation is the exchange of messages (that represent data
packets) between individual model components.
All messages are derived from the class
Message
and therefore
inherit the following characteristics:
- Messages have a length which is set to one by default. This length can be
set by the method
setLength(long)
and retrieved by
getLength()
.
Creating messages usually takes place in a generator (
Generator
). Generally a generator
contains an element of the class
MessageFactory
, which creates new
message objects. By using the port concept, a message is passed from one
model component to the next, whereby a reference to each message is
additionally passed on during the process of the handshake protocol between
two components.
Special Message Types
Within an individual model, it might be
necessary to have a message with special members.
LabelMessage
and
IPPacket
are two implemented examples.
LabelMessage
has one additional label whereas
IPPacket
includes the most important fields of
the IP header.