<H2><A NAME="Heading28"></A>8.16 The ROUTE block &amp; SEQUENCES element</H2>

<P><B>8.16.1 The `ROUTE' block</B></P>

<P>The <B>`ROUTE'</B> block is our first example of a transfer block (others
are <B>`TRANSPORT'</B> and <B>`CONVEY'</B>. Transfer blocks have the function
of moving or transporting entities from their current station to a new
station. </P>

<P>This is the simplest of the transfer blocks which assumes unconstrained
movement for the entity. That is once the transfer is underway it is assumed
that nothing can impede the transfer. The only assumption made</P>

<P>is that time may be required for the transfer to take place. As you
might anticipate two parameters are required for this block : the destination
station name or number and the time taken for the transfer.</P>

<P><B>Example 8.11</B></P>

<P>In the following fragment of ARENA code if the due_date is greater than
10 the entity is routed to the dispatch station with a time which is exponentially
distributed with a mean of 2 units otherwise the entity transfers directly
to the station `Storage'</P>

<img src=pilt17.gif> <br>

<P>NOTE the <B>`STATION' </B>Dispatch could be located anywhere in the
model diagram. There is no requirement for it to be in the proximity of
the <B>`ROUTE'</B> block.</P>

<P>As we have seen the system attribute `M' keeps track of the station
location of an entity. As soon as an entity passes through a <B>`ROUTE'</B>
block M is updated to the destination <B>`STATION'</B> irrespective of
how long it takes to travel there. You can view the name or number of a
entities M attribute at any time to discover its location, or its destination
if it is en route.</P>

