🚀 go-pugleaf

Has there been much work done on simulations of the upper layers for an
OSI "stack"?  There are many papers written on the simulation analysis
of the MAC and physical layers (layers 1,2) however I have not seen much
in the line of the network, transport, session, presentation, and 
application layers.  

My experience is that the majority of the application to application 
transit or lag time is due to the layers above the MAC.  The speed of the
MAC is almost insignificant because most implementation of the upper layers
are so inefficient.  These inefficiencies are mostly due to the nature of the
beast, the protocols have so many options.  Granted some newer implementations 
are beginning to utilize the bandwidth of the network.  The OSI Express card
from HP seems to be a step in the right direction.

Anyway back to my question, I am interested in a simulation model of the OSI
"stack", specifically the MAP stack.  For those not aware the MAP standard
calls for the following "stack":
	Physical:	Broadband 10 Mb/sec or carrierband 5 Mb/sec 802.4
	Link:		Class 1 LLC  ISO 802.2
	Network:	Connectionless with ES/IS  ISO 8473/9542
	Transport:	Class 4  ISO 8072/8073
	Session:	Basic Combined Subset  ISO 8326/8327
	Presentation;	ISO 8822/8823
The application layer can be FTAM, MMS, X.500, X.400 etc...
What I would like to model (and subsequently get simulation data output) is 
the queuing delays within the "stack" and the transmit times for various
transactions.  For example the time required to send a single application
layer PDU from one node to another. Or the time required to send multiple
PDU's, with the corresponding internal queue depths revealed.

Do I have to write this simulation myself or does something exists that I
can either reuse or modify?  

Is there a "prefered" simulation language of choice in the ISO land?  

Are SLAM, GPSS, SIMSCRIPT outdated, old technology?
Would something like C++, CSIM, or Smalltalk be "better" for this?

-- 
Ed Korsberg             E-mail: korsberg@aa.ab.com
Allen Bradley Inc.      phone:  313-998-2470
555 Briarwood Circle
Ann Arbor, Mich 48104