2.3.3.2  The Enhydra Architecture 

W e b   S e r v e r

A p p lic a tio n   F r a m e w o r k

T o o ls

P O

P r e s e n ta tio n  

X M L C

P r e s e n ta tio n   L a y e r

M a n a g e r

P O

W e b   S e r v e r  

A p p lic a t io n  

w it h   E n h yd r a  

W iz a r d

D ir e c t o r

B O

S e s s io n  

M u lt is e r v e r  

B u s in e s s   L a y e r

M a n a g e r

A d m in

B O

W e b   B r o w s e r

E n h yd r a  

K e lp  T o o ls

M u lt is e r v e r

D O

D a ta b a s e  

D a ta  L a y e r

D O D S

M a n a g e r

D O

JD B C

JD B C

In s ta n tD B

D a ta b a s e   S e r v e r

Figure 2: Enhydra Architecture 

As illustrated in Figure 2, the Enhydra application server consists of the following three 

components: 

   A Web server. The Web server can either be the Enhydra Multiserver, which is an HTTP 

1.1 Web server with servlet engine supporting the servlet API version 2.2, or any other 

Web server with servlet engine. Enhydra applications work with any standards compliant 

servlet runner. Figure 2 also shows Enhydra Director, which is a plug in available for 

several Web servers to provide load balancing to application servers while maintaining 

session affinity. 

   The Application Framework. Currently, Enhydra offers two distinct application models. 

The developer may either choose the Enhydra specific  Enhydra super servlet 

application framework , or the  servlet application framework  that follows J2EE 

standards. The differences are described in further detail below. 

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