<s>
The	O
Sniffer	B-Protocol
was	O
a	O
computer	O
network	B-Protocol
packet	I-Protocol
and	I-Protocol
protocol	I-Protocol
analyzer	I-Protocol
developed	O
and	O
first	O
sold	O
in	O
1986	O
by	O
Network	O
General	O
Corporation	O
of	O
Mountain	O
View	O
,	O
CA	O
.	O
</s>
<s>
By	O
1994	O
the	O
Sniffer	B-Protocol
had	O
become	O
the	O
market	O
leader	O
in	O
high-end	O
protocol	O
analyzers	O
.	O
</s>
<s>
According	O
to	O
SEC	O
10-K	O
filings	O
and	O
corporate	O
annual	O
reports	O
,	O
between	O
1986	O
and	O
March	O
1997	O
about	O
$933M	O
worth	O
of	O
Sniffers	B-Protocol
and	O
related	O
products	O
and	O
services	O
had	O
been	O
sold	O
as	O
tools	O
for	O
network	O
managers	O
and	O
developers	O
.	O
</s>
<s>
The	O
Sniffer	B-Protocol
was	O
the	O
antecedent	O
of	O
several	O
generations	O
of	O
network	O
protocol	O
analyzers	O
,	O
of	O
which	O
the	O
current	O
most	O
popular	O
is	O
Wireshark	B-Language
.	O
</s>
<s>
The	O
Sniffer	B-Protocol
was	O
the	O
first	O
product	O
of	O
Network	O
General	O
Corporation	O
,	O
founded	O
on	O
May	O
13	O
,	O
1986	O
by	O
Harry	O
Saal	O
and	O
Len	O
Shustek	O
to	O
develop	O
and	O
market	O
network	O
protocol	O
analyzers	O
.	O
</s>
<s>
In	O
1982	O
engineers	O
John	O
Rowlands	O
and	O
Chris	O
Reed	O
at	O
Nestar	O
’s	O
UK	O
subsidiary	O
Zynar	O
Ltd	O
developed	O
an	O
ARCNET	B-Protocol
promiscuous	O
packet	O
receiver	O
and	O
analyzer	O
called	O
TART	O
(	O
“	O
Transmit	O
and	O
Receive	O
Totaliser	O
”	O
)	O
for	O
use	O
as	O
an	O
internal	O
engineering	O
test	O
tool	O
.	O
</s>
<s>
At	O
Network	O
General	O
,	O
Saal	O
and	O
Shustek	O
initially	O
sold	O
TART	O
as	O
the	O
“	O
R-4903	O
ARCNET	B-Protocol
Line	O
Analyzer	O
(	O
‘	O
The	O
Sniffer’	O
)	O
”	O
.	O
</s>
<s>
They	O
then	O
reengineered	O
TART	O
for	O
IBM	O
’s	O
Token	B-Device
Ring	I-Device
network	I-Device
hardware	O
,	O
created	O
a	O
different	O
user	O
interface	O
with	O
software	O
written	O
in	O
C	O
,	O
and	O
began	O
selling	O
it	O
as	O
The	O
Sniffer™	O
in	O
December	O
1986	O
.	O
</s>
<s>
In	O
April	O
1987	O
the	O
company	O
released	O
an	O
Ethernet	O
version	O
of	O
the	O
Sniffer	B-Protocol
,	O
and	O
in	O
October	O
,	O
versions	O
for	O
ARCNET	B-Protocol
,	O
StarLAN	B-Protocol
,	O
and	O
IBM	B-General_Concept
PC	I-General_Concept
Network	I-General_Concept
Broadband	O
.	O
</s>
<s>
Protocol	O
interpreters	O
were	O
written	O
for	O
about	O
100	O
network	O
protocols	O
at	O
various	O
levels	O
of	O
the	O
protocol	B-Protocol
stack	I-Protocol
,	O
and	O
customers	O
were	O
given	O
the	O
ability	O
to	O
write	O
their	O
own	O
interpreters	O
.	O
</s>
<s>
The	O
product	O
line	O
gradually	O
expanded	O
to	O
include	O
the	O
Distributed	O
Sniffer	B-Protocol
System	O
for	O
multiple	O
remote	O
network	O
segments	O
,	O
the	O
Expert	O
Sniffer	B-Protocol
for	O
advanced	O
problem	O
diagnosis	O
,	O
and	O
the	O
Watchdog	O
for	O
simple	O
network	O
monitoring	O
.	O
</s>
<s>
Between	O
inception	O
and	O
the	O
end	O
of	O
1988	O
,	O
Network	O
General	O
sold	O
$13.7	O
M	O
worth	O
of	O
Sniffers	B-Protocol
and	O
associated	O
services	O
.	O
</s>
<s>
By	O
1995	O
Network	O
General	O
had	O
sold	O
Sniffer-related	O
products	O
totaling	O
$631M	O
at	O
an	O
average	O
gross	O
margin	O
of	O
77%	O
.	O
</s>
<s>
It	O
had	O
almost	O
1000	O
employees	O
and	O
was	O
selling	O
about	O
1000	O
Sniffers	B-Protocol
a	O
month	O
.	O
</s>
<s>
Weeks	O
later	O
,	O
Network	O
Associates	O
bought	O
Pretty	B-Application
Good	I-Application
Privacy	I-Application
,	O
Inc	O
.	O
(	O
“	O
PGP	O
”	O
)	O
,	O
the	O
encryption	O
company	O
founded	O
in	O
1991	O
by	O
Phil	O
Zimmerman	O
,	O
for	O
$35M	O
in	O
cash	O
.	O
</s>
<s>
In	O
mid-2004	O
,	O
Network	O
Associates	O
sold	O
off	O
the	O
Sniffer	B-Protocol
technology	O
business	O
to	O
investors	O
led	O
by	O
Silver	O
Lake	O
Partners	O
and	O
Texas	O
Pacific	O
Group	O
for	O
$275M	O
in	O
cash	O
,	O
creating	O
a	O
new	O
Network	O
General	O
Corporation	O
.	O
</s>
<s>
Netscout	O
marketed	O
"	O
Sniffer	B-Protocol
Portable	O
"	O
in	O
2013	O
,	O
and	O
in	O
2018	O
they	O
divested	O
their	O
handheld	O
network	O
test	O
tool	O
business	O
,	O
including	O
the	O
Sniffer	B-Protocol
,	O
to	O
.	O
</s>
<s>
Network	O
General	O
,	O
prior	O
to	O
the	O
merger	O
with	O
McAfee	O
,	O
had	O
filed	O
no	O
patents	O
on	O
the	O
Sniffer	B-Protocol
.	O
</s>
<s>
Network	O
General	O
Corporation	O
applied	O
for	O
a	O
trademark	O
to	O
“	O
Sniffer	B-Protocol
”	O
used	O
in	O
the	O
context	O
of	O
“	O
analyzing	O
and	O
testing	O
digital	O
traffic	O
operations	O
in	O
local	O
area	O
networks	O
”	O
on	O
May	O
30	O
,	O
1989	O
.	O
</s>
<s>
As	O
of	O
2021	O
that	O
trademark	O
registration	O
is	O
still	O
active	O
,	O
and	O
is	O
now	O
owned	O
by	O
NetScout	O
Systems	O
Inc	O
.	O
Network	O
General	O
also	O
owned	O
the	O
trademarks	O
to	O
“	O
Expert	O
Sniffer	B-Protocol
”	O
,	O
“	O
TeleSniffer	O
”	O
,	O
and	O
“	O
Distributed	O
Sniffer	B-Protocol
System	O
”	O
,	O
all	O
of	O
which	O
have	O
expired	O
.	O
</s>
<s>
The	O
ARCNET	B-Protocol
Sniffer	B-Protocol
developed	O
as	O
an	O
internal	O
test	O
tool	O
by	O
Zynar	O
used	O
the	O
IBM	O
PC	O
ARCNET	B-Protocol
Network	O
Interface	O
Card	O
developed	O
by	O
Nestar	O
for	O
the	O
PLAN	O
networking	O
systems	O
.	O
</s>
<s>
That	O
board	O
used	O
the	O
COM9026	O
integrated	O
ARCNET	B-Protocol
controller	O
from	O
Standard	O
Microsystems	O
Corporation	O
,	O
which	O
had	O
been	O
developed	O
in	O
collaboration	O
with	O
Datapoint	O
.	O
</s>
<s>
There	O
was	O
no	O
promiscuous	B-Protocol
mode	I-Protocol
in	O
the	O
SMC	O
chip	O
that	O
would	O
allow	O
all	O
packets	O
to	O
be	O
received	O
regardless	O
of	O
the	O
destination	O
address	O
.	O
</s>
<s>
So	O
to	O
create	O
the	O
Sniffer	B-Protocol
,	O
a	O
daughterboard	O
was	O
developed	O
that	O
intercepted	O
the	O
receive	O
data	O
line	O
to	O
the	O
chip	O
and	O
manipulated	O
the	O
data	O
so	O
that	O
every	O
packet	O
looked	O
like	O
a	O
broadcast	O
and	O
was	O
received	O
by	O
the	O
chip	O
.	O
</s>
<s>
The	O
source	O
code	O
of	O
the	O
original	O
TART/Sniffer	O
BASIC	O
and	O
assembler	O
program	O
is	O
available	O
on	O
GitHub	O
.	O
</s>
<s>
The	O
Sniffer	B-Protocol
was	O
a	O
promiscuous	B-Protocol
mode	I-Protocol
packet	O
receiver	O
,	O
which	O
means	O
it	O
received	O
a	O
copy	O
of	O
all	O
network	O
packets	O
without	O
regard	O
to	O
what	O
computer	O
they	O
were	O
addressed	O
to	O
.	O
</s>
<s>
The	O
packets	O
were	O
filtered	O
,	O
analyzed	O
using	O
what	O
is	O
now	O
sometimes	O
called	O
Deep	B-Application
Packet	I-Application
Inspection	I-Application
,	O
and	O
stored	O
for	O
later	O
examination	O
.	O
</s>
<s>
The	O
Sniffer	B-Protocol
was	O
implemented	O
above	O
Microsoft	O
’s	O
MS-DOS	B-Application
operating	O
system	O
,	O
and	O
used	O
a	O
40	O
line	O
80-character	O
text-only	O
display	O
.	O
</s>
<s>
The	O
first	O
version	O
,	O
the	O
PA-400	O
protocol	O
analyzer	O
for	O
Token-Ring	B-Device
networks	I-Device
,	O
was	O
released	O
on	O
a	O
Compaq	B-Device
Portable	I-Device
II	I-Device
“	O
luggable	O
”	O
computer	O
that	O
had	O
an	O
Intel	O
80286	O
processor	O
,	O
640	O
KB	O
of	O
RAM	O
,	O
a	O
20	O
MB	O
internal	O
hard	O
disk	O
,	O
a	O
5	O
¼	O
”	O
floppy	O
disk	O
drive	O
,	O
and	O
a	O
9	O
”	O
monochrome	O
CRT	O
screen	O
.	O
</s>
<s>
As	O
the	O
Sniffer	B-Protocol
manual	O
described	O
,	O
“	O
The	O
screen	O
shows	O
you	O
three	O
panels	O
,	O
arranged	O
from	O
left	O
to	O
right	O
.	O
</s>
<s>
In	O
the	O
multiple-packet	O
summary	O
,	O
the	O
default	O
display	O
was	O
of	O
information	O
at	O
the	O
highest	O
level	O
of	O
the	O
protocol	B-Protocol
stack	I-Protocol
present	O
in	O
that	O
packet	O
.	O
</s>
<s>
The	O
translation	O
of	O
data	O
at	O
a	O
particular	O
level	O
of	O
the	O
network	B-Protocol
protocol	I-Protocol
stack	I-Protocol
into	O
user-friendly	O
text	O
was	O
the	O
job	O
of	O
a	O
“	O
protocol	O
interpreter	O
”	O
,	O
or	O
PI	O
.	O
</s>
<s>
Sniffer	B-Protocol
customers	O
could	O
write	O
their	O
own	O
protocol	O
interpreters	O
to	O
decode	O
new	O
or	O
rare	O
protocols	O
not	O
supported	O
by	O
Network	O
General	O
.	O
</s>
<s>
Interpreters	O
were	O
written	O
in	O
C	O
and	O
linked	O
with	O
the	O
rest	O
of	O
the	O
Sniffer	B-Protocol
modules	O
to	O
create	O
a	O
new	O
executable	O
program	O
.	O
</s>
<s>
The	O
procedure	O
for	O
creating	O
new	O
PIs	O
was	O
documented	O
in	O
April	O
1987	O
as	O
part	O
of	O
Sniffer	B-Protocol
version	O
1.20	O
.	O
</s>
<s>
In	O
addition	O
to	O
supporting	O
many	O
network	O
protocols	O
,	O
there	O
were	O
versions	O
of	O
the	O
Sniffer	B-Protocol
that	O
collected	O
data	O
from	O
the	O
major	O
local	O
area	O
networks	O
in	O
use	O
in	O
the	O
1980s	O
and	O
early	O
1990s	O
:	O
</s>
<s>
Even	O
in	O
the	O
early	O
years	O
,	O
the	O
Sniffer	B-Protocol
had	O
competition	O
,	O
at	O
least	O
for	O
some	O
aspects	O
of	O
the	O
product	O
.	O
</s>
<s>
Several	O
were	O
,	O
like	O
the	O
Sniffer	B-Protocol
,	O
ready-to-use	O
packaged	O
instruments	O
:	O
</s>
