Simulation Model and Studies of MIL-STD-188-220A’
Dr. David J, Thuente 2
Department of Computer Science
Indiana University Purdue University Fort Wayne
Fort Wayne, Indiana 46815
email: thuente @ipfw.edu
Timothy E. Borchelt
Raytheon Systems Company
Fort Wayne, Indiana, 46808
email: teborc (i?most.fw.hac.com
ABSTRACT
for the media access control (MAC) algorithms DAP-NAD
and RE-NAD for multiple small j%-e direction subnets and
for larger single network configurations.
The model has
shown the eflects of blocking via physical obstructions or
jamming
on network pe~ormance.
We have also
demonstrated the ability of both DAP-NAD and RE-NAD
to continue to efficiently operate on a disconnected
network and to eventually reconnect the network when
physically possible.
A detailed model for the analysis and evaluation of many
aspects of the protocol MIL-STD-188-220A
has been built.
This model has been used to develop important results
about the pe~ormance of MIL-STD-188-220A for various
network configurations and message types and loads. The
model includes detailed implementations
in OPNET of
many of the features of MIL-STD-188-220A
including
Type 1 and Type 2 services, deterministic
adaptable
priori~
network access delay (DAP-NAD) and radio
embedded network access delay (RE-NAD) media access
control algorithms, intranet topology with all appropriate
updates, topology requests, and the transmission of all
topology messages with the exact size and timing of the
messages
dictated
by the protocol.
Blocking
of
transmissions
to individual nodes, either forced
by
obstructions
or partial or total blocking forced by
jamming, and intranet relaying using the topology routing
tree graph have been implemented and used to obtain
results.
The model incorporates mobile receiver and
transmitter nodes as well as fixed or mobile jammer
nodes. The jammer nodes can have isotopic antennas or
antennas with dB gains in cones with fixed direction
pointing or dynamic direction pointing toward a target.
Bit error rate (BER) and correction using the 24/12 Golay
algorithm is efficiently modeled at the bit level.
We have obtained some quite definitive results about
which parts of the MIL-STD-188-220A
protocol should be
used under various network and message size and
frequency configurations.
These results should be ve~
useful to the users and potential users of this protocol.
Significant comparative results have been obtained as
baselines for fire support and situation awareness type
messages. We contrast the perj40rmance of the networks
1‘This effort was internally funded by Hughes Aircraft
Corporation as a Corporate Special Programming project.
2This author is a consultant on communications protocols at
Hughes Defense Communications. Both Hughes Aircraft
Corporation and Hughes Defense Communications are now part
of Raytheon Systems Company.
INTRODUCTION
This paper discusses and presents results from a detailed,
low-level, and high fidelity model of most parts of the
MIL-STD-1 88-220A with particular emphasis on intranet
relaying,
intranet
topology
with the corresponding
topology
updates
and requests,
node blocking
by
obstructions or partial or total blocking by jamming. The
model also includes various forms of jammer nodes,
mobile nodes, BER and a faithful simulation of the 24/12
Golay error correction.
The paper also includes a
discussion of how the MAC algorithms affect performance
under different
configurations
of the above model
parameters.
This work presented here is a major extension of the
model and results reported at MILCOM 97 (Ref. 10).
That model
was developed
partially
for the
communication performance modeling of the Advanced
Data System
(AFATDS)
Field Artillery
Tactical
communications system. The AFATDS datalink protocol
modeled is very similar to, but was not strictly MIL-STD188-220A compliant. These previous results focused on
the optimization of the DAP-NAD for fire support (FS)
operations
and, in particular,
on the assigning of
subscriber numbers for efficient communication
on a
That
paper
also
did
some
DAP-NAD
network.
preliminary comparison of DAP-NAD and RE-NAD for
The results here considerably
FS mission throughput.
extend that work to include a more thorough comparison
of these two MAC algorithms for many scenarios that can
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be done now because our MIL-STD-1 88-220A model is
more complete.
knows it has received, and hence knows the remaining
packets were not correctly received.
There is a continued emphasis on the importance of
modeling
and simulation
in the development
of
communication systems and in the use of simulation for
the design, implementation, operation and administration
of battlefield networks (Ref. 6). There is a reasonable
consensus that OPNET is the communication modeling
tool of choice for the military (Refs. 2, 6, 9, 10, 11, 12).
Moreover,
the
uses
because
Army
multiple
communication
systems,
including
Single
Channel
Ground and Airborne Radio System (SINCGARS),
Enhanced Position Location Reporting System (EPLRS),
Mobile Subscriber
Equipment
(MSE), asynchronous
transfer mode (ATM), and satellite communications that
must interface into an efficient network of networks,
simulation is required “early and often” as the title of a
recent article in Signal (Ref. 9) states.
MIL-STD- 188-220A has five different MAC algorithms.
DAP-NAD and RE-NAD are the two MAC algorithms
examined in this paper. Previous experiments have shown
that R-NAD, P-NAD, and H-NAD (random, priority, and
hybrid respectively) having serious limitations for FS
applications.
DAP-NAD
is a method of generating
network access delays, which provides every subscriber an
equal opportunity to use the network. It is deterministic in
that each subscriber can determine the maximum amount
of time before their next network access opportunity.
When subscribers sense the end of the transmission,
subscribers compute a series of network access times,
unique for that subscriber, based on
●
their subscriber number; each subscriber is assigned a
unique number in the range 1 to the total number of
subscribers
●
which subscriber is to have the first access opportunity
●
the network precedence: urgent, priority , or routine
●
the message precedence of the highest precedence
message in the subscriber’s own queue.
From any node’s point of view, if no other subscriber
starts transmitting before that node’s network access
times occurs then that node will transmit. The formulas
for computing the access slots are given in (Refs. 3, 5).
MIL-STD-188-220A
and the SIMULATION
MODEL
MlL-STD-l 88-220A
is being defined to facilitate
interoperability
between
battlefield
communication
systems and is concerned with the network (partial),
datalink, and physical layers of the 0S1 stack. It has been
under development since 1993 by the Combat Net Radio
(CNR) Working Group and a draft of the current version
at the standard
can be found
at http://wwwcnrwg.itsi.disa. roil/.
MIL-STD-188-220A
supports Type 1, 2, 3, and 4
services. Type 1, 3, and 4 are connectionless operations
with Type 1 being unacknowledged, Type 3 requiring an
immediate
acknowledgment
(also
called
coupled
acknowledged Type 1 in MIL-STD-188-220A)
and Type
4 using decoupled acknowledgments.
Type 2 services are
connection oriented with decoupled acknowledgments
and are based on the HDLC (high-level datalink control)
protocol.
Type 2 services provide high reliability
because of the connection state but do not require
individual acknowledgments.
In most heavily used
networks, Type 2 acknowledgments are included in other
packet headers via piggy backing and incur little or no
For reliable transfer of large
additional overhead.
amounts of data, Types 2 and 4 are generally used. Type
2 is considered more efficient since it does not require
separate acknowledgments for each packet. The model
and simulations presented in this paper are based on Type
For experimentation
2 services or transmissions,
purposes, implicit rejects of Type 2 service messages
have been incorporated even though it is not currently
part of MIL-STD-1 88-220A. Implicit rejects occur when
the receiver acknowledges fewer packets than the sender
The RE-NAD algorithm dynamically controls network
access based on network load, network topology, and
The algorithm
uses a “continuous
load factors.
scheduler” based on queue lengths, average concatenated
network
partition
factors,
network
frame lengths,
topology factors and load and priority statistics at
RE-NAD uses two levels of
neighboring
nodes.
algorithms for media access control:
(1) modem to radio; the continuous scheduler,
defined in the standard
(2) radio to radio; the radio embedded portion, not
defined in the standard.
RE-NAD uses a continuous scheduler interval computed
as sum of fixed part and a random part; range is 1.0 ..30.0
seconds. The fixed part is based the average duration of a
station’s last four transmissions ; valid range is 1 .. 10
seconds and the random part is a random number between
0.0 and schedint; where schedint is a MIL-STD-188-220A
defined variable for RE-NAD between 3.0 and 20.0.
Schedint is based on the average duration of a station’s last
four transmissions, the ratio of the number of nodes two
hops away versus one hop away, the advertised load of all
nodes on the network, and a factor indicating how strongly
Finally, RE-NAD uses
connected
the network is.
Immediate Mode Scheduling to increase utilization of
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large lightly loaded networks.
If
the continuous scheduler expires
and there are no packets to send,
then when packets do become
available, the current scheduler is
canceled and scheduler timer is
set to 0.1 second.
Segmentation and reassembly
TCP(COTS)
Transport
-------------------------Internet
Network
Intranet
-------------.---------.--
Selective Directed Broadcast
.
Procedures
The model, as stipulated in MILDatalink
Media Access Control
for
STD-1 88-220A,
allows
-------------------------intranet
intranet
relaying,
Physical
topology with the corresponding
topology updates and requests. In
these
order
to
accomplish
functions
each node stores a Figure 1. MIL-STD 188-220A Protocol and Modeled Architecture
routing tree graph which contains:
obtain desired model characteristics.
The model simulates
(1) inforrnatlon-about the link between each node and its
absolute terrain blockage between arbitrary nodes and also
neighbors; (2) number of hops to each node, dependent on
allows for partially or totally disabling particular nodes
the path taken; (3) cost or link quality for each link; (4)
using jammers.
Background noise can be specified for
each node’s relay status (a node may refuse to relay
each node individually. The signal-to-noise-ratio (SNR) is
packets); (5) each node’s quiet status (a node may just
computed as the sum of all of the signal inputs at a node.
listen and refuse to transmit). A necessary part of intrartet
At every change in the SNR, the BER from the previous
relaying for dynamic
subnets is topology updates.
SNR change to the current SNR change is computed. This
Topology updates are a sparse version of the routing tree
computation of the BER is used to drive the detailed
which has at most only two entries per node, each being
simulation of the 24/12 Golay forward error correction
unique. Topology updates are sent whenever a node has
(FEC).
Every transmission unit (TU) has its header
made a change in its routing tree graph but may be sent no
examined using FEC and the TU is rejected if its header
more often than a user defined interval which is defined in
has errors that cannot be corrected with 24/12 Golay.
minutes. Topology updates are distributed in a Topology
Every BER change is applied to the exact set of bits
Update Packet. Topology requests are sent to neighboring
affected by that particular BER even if BER is contained
nodes when a node receives an update that is different than
in or crosses any combination of TU headers, interior
the last update received from the node that sent the update.
transmission unit (ITU) headers, ITUs, time dispersal
Topology requests may be sent no more often than twice
coding (TDC) blocks, Golay blocks or DLPDUS. In sum,
the rate of topology updates.
the computed BER is applied faithfully across the entire
The intranet relay allows for relaying of transmission units
transmission
and each block is accepted or rejected
or datalink layer protocol data units (DLPDU) between
appropriately.
nodes that are not directly connected but on the same radio
The general assumption of 4800 bps on any channel is
network.
It uses information stored in the topology
made for all radio connections. The Type 2 information
routing tree graph to do source directed routing and also
frame has a minimum header size of 336 bits and allows
The intranet header is used to
allows for multicasting.
16 destination addresses of 24 bits each. Each relayer or
indicate the DLPDU route and each node that is to be a
destination for intranet relaying requires 16 bits plus one
relay and each node that is a destination for the DLPDU.
48 bit block for relaying. The transmission word count
The physical layer of the simulation model consists of
and the transmission header always have Golay FEC and a
radio transmitters and receivers. Both the transmitters and
168 bit TDC block applied. The physical payload may
The
receivers may be mobile and at any altitude.
optionally have Golay FEC, a 384 bit TDC block or
transmitters
may also be jamrners
with their own
scrambling applied. After 20 seconds, unacknowledged
trajectories
and particular modulation
algorithms for
messages are retried and may be transmitted a total of four
jamming. All transmitters, including jammers, also have
times at the datalink layer before being discarded.
their own antenna patterns, user-defined focus, and gain.
Many parameters of interest are read from a text file at the
All of the radios transmit with user specified modulation
More than 64 of these
start of a simulation run.
algorithms at user specified frequencies, bandwidth and
parameters can be set to vary network characteristics.
power. The OPNET pipeline stages have been modified to
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Among the parameters that can be set to affect network
performance are: network bit rate, datalink layer timers,
maximum retransmission values, use of FEC and TDC,
use of topology
updates
and relaying,
jamming
characteristics, mission types to be run (each type can be
started independently
and may have a uniform or
exponential starting rate or may be stimulated by a timedordered-event-list).
Other parameters read in but typically
not changed between runs include network and physical
addresses, radio frequencies, bandwidth, and modulation
techniques used. In addition, a complete set of optional
debugging parameters can be specified in this input file so
that most any characteristic of the transmissions can be
seen on the debug screen. For example, this includes the
dynamic setting up of the Type 2 connections,
the
retransmit tries, and the run time SNRS and BERs and the
acceptance of every TU header and every packet within
the TU. This feature of the model has been very important
for our verification and validation efforts.
request message that triggers a sequence of 15 messages,
varying in length from 13 to nearly 200 bytes, and their
acknowledgments that are transmitted, using Type 2, on
the brigade network and the fire direction networks. The
situation awareness (SA) message is assumed to be a 240
bit message and is sent using Type 1 services.
The first scenario consists of nine active nodes spread
over three networks with a single gateway node, the
bn_cp, which connects the two fire direction networks
with the brigade network. For the FS message set, the
brigade network is much more heavily loaded than the
fire direction networks.
This scenario assumes the
networks are connected and error free. The jammer was
not used.
The only errors came from collisions of
messages when using RE_NAD.
The layout of this
scenario is given in Figure 2.
The verification and validation of the model has been a
continuous activity throughout its development.
It has
been verified in accordance
with (Ref. 4).
The
configuration of early versions of the model was exactly
the same as the configuration in the lab with actual radio
networks.
That validation of the early model was very
successful and has been reported in considerable detail
elsewhere (Refs. 1, 7, 8), While we have not repeated this
validation
effort with lab data, current results are
consistent
with previous
results
when appropriate
simplifying assumptions are made.
SIMULATION
SCENARIOS
and RESULTS
There are a multitude of different, interesting, and
beneficial scenarios and simulations that could be run
using this model.
We have already made many
interesting runs and have a number of additional runs
planned that have helped and will help determine how to
configure
MIL-STD-188-220A
for
the
AFATDS
applications.
One area that we have examined is the
question of the MAC algorithms. This is a fundamental
design choice that needs to be made and then that choice
needs to be tuned for the capabilities of the radios and the
requirements of the applications.
There are two fundamentally different types of message
sets that need to be transmitted using MIL-STD-1 88220A. The FS message set is a threaded message set
which has corresponding transport or application level
acknowledgments.
For our FS message set, we use a fire
Figure 2. Basic Three Fire Support Networks
A detailed description of the message set for this scenario
is given in (Refs. 7, 8). This basic scenario is critical to
the success of the FS mission,
There have been
numerous runs of the model with both DAP-NAD and
RE-NAD MAC algorithms. It can be shown, for DAPNAD, the knee of the curve for time-to-completion
of
threads is around a 210 thread offered load (exponential
arrivals over approximately 3300 seconds so that the
threads can complete in an hour). Figure 3 gives the
thread completion times for an offered load of 200
threads. The graph shows a stable system, with all threads
completing,
that could be expected
to function
indefinitely at this offered load.
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The next scenario is an extension of that given above.
One fire direction network is spread out so that it requires
relaying in order to transmit messages to the most distant
node and the relay node is periodically blocked using a
jammer. The laydown is given in Figure 4.
threadmissiontinxxbn.fse threadtype O
~ 200
e 190
.
...........
c 180
......
...........
0 i7~
..
. .
n 160
.....
...........
d
150
s
.
............
0
i
2
3
4
Fire direction network 2 (FD2) consists of the nodes
bn_cp, FU_2A, FU_2B, and FU_2C. FU_2A cannot be
reached directly from bn_cp and hence FU_2B must relay
messages between them. The fire units do not normally
require communication between each other. In addition
to relaying, this scenario examines blocking which in this
case, actually severs the FD2 network. The jammer j ams
the FU_2B nodes for 100 seconds every 400 seconds.
Since four transmissions are made with 20 second timers
before a packet is discarded, the effect of this 100 second
jamming is that the Type 2 connection between the
bn_cp and FU_2B nodes and the connection between
FU_2B and FU_2A nodes is broken. When the jamming
5
tirn3 seconds(x 1000)
Figure 3. Thread completion times for offered load of 200
threads,
If the same scenario is run using RE-NAD, fewer than
100 threads will complete and it will take well over an
hour for them to do so. Consequently, the offered load
was reduced to 150 threads.
The average number of
threads completed
using
RE-NAD
I
I
I
was
I
I
I
approximately 80.
bde_f se
Threads
failed
because
Q@
Q
individual
bn_f se
, i, tim
moni’t or_b de
messages in the
threaded message
Q
0
(3o
FU:2B
FU:2A
FU-IR
set failed to be
@
“’-”P
@
~
o
successfully
rif d2
monitor_f dl
jarher
transmitted in the
WJB
four transmissions
o
Q
retry
limit
and
FU:2C
FVJ c
were
discarded.
The only reason a
message failed to
Figure 4. Fire Support Network with Relaying and Blocking
be
successfully
transmitted
was
because
of
ends, network control messages that are being transmitted
collisions due to the RE-NAD algorithm. It is clear that
to restore connections can be received. We are assuming
DAP-NAD is superior to RE-NAD for this application
that the networks have simple frequency hopping so that
and network laydown.
the radios will synchronize
with the first valid
The above simulations have been repeated for RE-NAD
transmission header it hears.
The comparison of the
and DAP-NAD with both a stationary and a mobile
DAP-NAD and RE-NAD performance is again quite
jammer and with isotropic and focused jammer antennae.
interesting.
The number of mission threads that have
The results were essentially consistent with those just
completed processing at the fire units is tallied for each
given but the percentage drop in the missions completed
MAC algorithm and for non-jamming and intermittent
using RE-NAD was not quite as great. This was to be
jamming situations. The offered load for each fire unit is
expected since only half of the offered mission threads
25 missions. Table 1 gives the results,
were completing in an error free environment.
It is clear that DAP-NAD performs better than RE-NAD
in this situation. The same conclusion is also obtained if
I
o
monito
I
0-7803-4902-4/98/$10.00 (c) 1998 IEEE
I
I
I
the total number of missions completed is tallied at either
the bn_cp or at the bn_fse. Counting the total at the fire
units gives a better indication of the immediate impact of
both relaying and jamming the relayer and the destroying
of the Type 2 connections.
Non-jamming
FU.2B
I Fu_2A
received all 1256 messages while RE-NAD received only
770 messages.
node 4 packet hop timex seconds
Jamming
FU.2B
1 Fu_2A
11
24
8
25
19
14
6
4
RE-NAD
Table 1. Comparison of DAP-NAD and RE-NAD with
Relaying and Jamming Missions completed at the Fire Units
DAP-NAD
From the previous two scenarios it can be concluded that
DAP-NAD outperforms RE-NAD for FS missions on
small networks in error free, relaying, or jamming
The next scenario examines the relative
situations.
performance of the MAC algorithms on a 16 node
network broadcasting, using Type 1 services, SA type
messages of 240 bits each every 12 seconds distributed
exponentially. The network is given in Figure 5.
...........................
node_l
Q
3
tim
@
o
1
seconds (x 1000)
Figure 6. Packet Hop times for DAP-NAD
detect-time :0.41 sec.)
(net-busy-
node 4 packet hop times seconds
20
s 17.5
e 15
c12.5
d5
s 2.5
0
0.1 0.2 0.3
no de_l 2
node_3
Q
node_li
o
no de_4
no de_5
0.7 0.8 0.9
c1
node_2
o
0.4 0.5 0.6
o 10
n 7.5
c)
no de_:
.. ... . .... ... .... ...
0.1 0.2 0.3
..
.......... ..................... .....Q ...................
0
node_10
o
LO
.
de_6
n
w~ode
(7I
‘0”-9
‘
~ node_*
Figure 5. Single level 16 node Situation Awareness type
of Network
Since there are no threaded messages or internet or
intranet relaying, the critical performance factor is the
time between the creation of the packet or SA message
and the time it is delivered - called the packet hop time.
This is a critical measure for SA data. Sixteen nodes
create messages on average every 12 seconds - so a total
of approximately 1250 messages would be created in the
These messages
are
1000 second simulation runs.
broadcast to the 15 other nodes. Figure 6 and 7 give the
packet hop times with averages of 11.5 and 2.9 seconds
for DAP-NAD and RE-NAD respectively.
DAP-NAD
0.4 0.5 0.6 0.7 0.s 0.9
tirnz seconds (x 1000)
1
;igure 7. Packet Hop times for RE-NAD (net-busy-detecttime :0.41 sec.)
Close examination of the results shows that nearly 500
more messages were received under DAP-NAD than
under RE-NAD.
This accounts for the more than 5
seconds of the difference in the average hop time. A hop
time that more accurately reflects the true performance
DAP-NAD and RE-NAD is given by 6 seconds versus 2.9
seconds. The key parameter for DAP-NAD is the netbusy-detect-time which has been set to 0.41 seconds for
our simulation rnns. If the radio configuration has a
squelch pin, then using the squelch pin may allow the netbusy-detect-time to be set as low as 0.1 seconds. Figure 8
gives the packet hop times for DAP-NAD using a netbusy-detect-time of 0.1 seconds. The average hop time is
now 2.1 seconds. The simulation was repeated for RENAD and the average decreased only to 2.7 seconds.
Most SINCGARS radios have this squelch pin and hence
it is critical for network performance using DAP-NAD
that it be used and configured into the network operation.
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node 4 packet hop times: seconds
except
for
possible
DAP-NAD
will,
circumstances, be the MAC algorithm of choice.
0
There is also the question of Type 2 versus Type 4
services that should be investigated. All of the work for
Type 2 services for DAP-NAD and RE-NAD needs to be
repeated for Type 4 services and then comparisons of
Type 2 and Type 4 services could be made. The datalink
layer parameter settings such as ACK timer, response
timer, and retransmission count need to be investigated
for DAP-NAD and RE-NAD when using Type 4.
12.5
s 10
e
~ 7.5
05
n
d2.5
s
o
CI.I 0.2 0.3
0.4 0.5
0.6 0.7
0.8 0.9
1
time: seconds (x 1000)
Figure 8. Packet Hop times for DAP-NAD
detect-time :0.1 sec.)
(net-busy-
REFERENCES
1.
C. D. Brown, “AFATDS Communication Performance
Model Simulation Build lC Validation Test Procedure,”
Magnavox Electronic Systems Co., February 9, 1996
2.
Geoffrey R. Kelsch, “A Common Tactical Internet
Architecture,”
Model
MILCOM’97
Performance
Conference Proceedings, Nov. 2-5, 1997, pp. 177-181.
3.
Magnavox Electronic Systems Company, “VMF Technical
Interface Design Plans,” January 1993.
4.
“Verification, validation, and Accreditation of Army
Models and Simulations,” Army Pamphlet 5-11, 15
October, 1993.
5.
MIL-STD-1 88-220A “Interoperability Standard for Digital
Message Device Transfer Subsystems”, 5 February 1997.
6.
Clarence A. Robinson, Jr., “ Warjighter Information
Network Harnesses Simulation Validation, ” Signal,
January 1998, pp. 27-32.
7.
David J. Thuente, Craig Brown, Tim Borchelt, Ed Hill,
CONCLUSIONS
The single most important conclusion is that this model
of the MIL-STD-1 88-220A protocol can be of great
benefit in the design and implementation of the Army
radio communication networks that use the MIL-STD188-220A protocol.
There are many choices for the
implementation of MIL-STD- 188-220A and it is crucial
that the right choices be made for various applications.
This model can be a large asset in making certain that
MIL-STD-188-220A
is utilized correctly or efficiently.
Though it was not shown in this paper, this model can
also be used to determine
near optimal jamming
strategies for radios using MIL-STD-1 88-220A.
In the
future, it maybe possible to configure radios using MLLSTD-1 88-220A so as to minimize the effects of those
same jamming strategies.
The high variability in the performance and response
times for RE-NAD makes it a poor choice for most
applications
that require
anything
even remotely
resembling real-time performance.
It appears that DAP-NAD is the MAC algorithm of
choice for FS applications and their networks. The netbusy-detect-time is a key parameter for DAP-NAD. If the
net-busy-detect-time
can be brought into the range of 0.1
seconds, then DAP-NAD
appears to be the MAC
algorithm for most modest sized networks of up to 20
nodes regardless of the applications that are being run on
the communication network. The SINCGARS ICOM or
SIP R/T radios already provide the ability to signal net
busy to an attached MIL-STD-1 88-220A adapter via
voltage change on the squelch pin of the six pin data
connector. In order to improve network performance, it
is important that all MIL-STD- 188-220A adapter have the
ability to sense this signal. This allows the net-busydetect-time to be reduced to the 0.1 second range. If
available, it is important that this feature be used and then
special
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Network
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Report,”
Magnavox
Electronic Systems Co., Fort Wayne, IN, October 13, 1995.
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David J. Thuente, Craig Brown, Tim Borchelt, Ed Hill,
“The Design and Analysis of the AFATDS Communication
Networks using Simulation,” Proceedings 1996 Tactical
Communication Conference, April 30-May 2, 1996, pp.
267-280.
9.
“System
Complexity
Requires
David
J. Thuente,
Simulation Early and Often,” Signal (AFCEA Publication),
August 1996, pp. 65-67.
10. David J. Thuente and Tim Borchelt, “Simulation Studies of
MAC Algorithms
for Combat
Net Radio,” MILCOM’97
Conference Proceedings, Nov. 2-5, 1997, pp. 193-199.
11. Patrick D. Dye, “Joint Staff Requests
Aid in Locating
OPNET Models of Battlefield Communications Systems,”
12/2/97, posted on www.mi13.com.
12. Chuck Wong and Mark Bradley, “The Role of Modeling
and Simulation in Sizing Military Networks,” MILCOM’96
Conference Proceedings, Oct. 21-24, 1996, pp. 623-626.
0-7803-4902-4/98/$10.00 (c) 1998 IEEE