<s>
DSRFLOW	B-Protocol
,	O
the	O
Flow-State	O
extensions	O
to	O
Dynamic	B-Device
Source	I-Device
Routing	I-Device
(	O
DSR	O
)	O
,	O
are	O
a	O
set	O
of	O
extensions	O
that	O
provide	O
all	O
of	O
the	O
benefits	O
of	O
source	O
routing	B-Protocol
,	O
without	O
most	O
of	O
the	O
per-packet	O
overhead	O
that	O
is	O
associated	O
with	O
source	O
routing	B-Protocol
.	O
</s>
<s>
It	O
works	O
by	O
allowing	O
most	O
packets	B-Protocol
to	O
be	O
sent	O
without	O
a	O
source	O
route	O
header	O
,	O
thus	O
substantially	O
reducing	O
overhead	O
.	O
</s>
<s>
Indeed	O
,	O
one	O
of	O
the	O
disadvantages	O
of	O
DSR	O
was	O
that	O
the	O
longer	O
the	O
source	O
route	O
of	O
the	O
packet	B-Protocol
was	O
,	O
the	O
bigger	O
the	O
packet	B-Protocol
header	O
became	O
.	O
</s>
<s>
The	O
technique	O
used	O
is	O
called	O
implicit	O
source	O
routing	B-Protocol
.	O
</s>
<s>
Flow	O
state	O
extensions	O
to	O
DSR	O
were	O
first	O
described	O
in	O
"	O
Implicit	O
Source	O
Routes	O
for	O
On-Demand	O
Ad	O
Hoc	O
Network	B-Protocol
Routing	I-Protocol
"	O
by	O
Yih-Chun	O
Hu	O
and	O
David	O
B	O
.	O
Johnson	O
(	O
2001	O
)	O
.	O
</s>
<s>
The	O
implicit	O
source	O
routing	B-Protocol
mechanism	O
is	O
now	O
included	O
in	O
the	O
DSR	O
Internet	O
Draft	O
.	O
</s>
<s>
The	O
main	O
idea	O
of	O
DSRFLOW	B-Protocol
is	O
to	O
introduce	O
a	O
so-called	O
flow	O
table	O
for	O
each	O
network	O
node	O
and	O
thus	O
making	O
DSRFLOW	B-Protocol
a	O
stateful	O
routing	B-Protocol
protocol	O
.	O
</s>
