<s>
The	O
Cisco	B-Device
2500	I-Device
series	I-Device
routers	O
are	O
a	O
series	O
of	O
19	O
"	O
rack	O
mount	O
access	O
routers	O
typically	O
used	O
to	O
connect	O
Ethernet	O
or	O
Token	B-Device
Ring	I-Device
networks	I-Device
via	O
ISDN	B-Protocol
or	O
leased	O
serial	O
connections	O
(	O
i.e.	O
</s>
<s>
Frame	B-Protocol
Relay	I-Protocol
,	O
T1	B-Protocol
etc	O
.	O
)	O
.	O
</s>
<s>
Supported	O
interfaces	O
:	O
Ethernet	O
(	O
10	O
Mbit/s	O
)	O
,	O
Token	B-Device
Ring	I-Device
(	O
16	O
Mbit/s	O
)	O
,	O
ISDN	B-Protocol
BRI	I-Protocol
(	O
128	O
kbit/s	O
)	O
,	O
Sync	O
Serial	O
(	O
2	O
Mbit/s	O
)	O
,	O
Async	O
Serial	O
.	O
</s>
<s>
The	O
modular	O
routers	O
had	O
3	O
interface	O
slots	O
available	O
–	O
2	O
Synchronous	O
Serial	O
and	O
1	O
ISDN	B-Protocol
.	O
</s>
<s>
The	O
ISDN	B-Protocol
modules	O
were	O
keyed	O
so	O
as	O
not	O
to	O
be	O
inserted	O
into	O
a	O
Synchronous	O
WAN	O
module	O
slot	O
.	O
</s>
<s>
A	O
'	O
Mission-specific	O
'	O
model	O
could	O
be	O
upgraded	O
to	O
full	O
router	O
capability	O
by	O
installing	O
a	O
full	O
featured	O
IOS	B-Protocol
image	O
and	O
(	O
if	O
necessary	O
)	O
adding	O
memory	O
.	O
</s>
<s>
There	O
routers	O
were	O
mainly	O
intended	O
to	O
be	O
frame	B-Protocol
relay	I-Protocol
access	O
devices	O
.	O
</s>
<s>
The	O
'	O
CF	O
 '	O
in	O
the	O
model	O
number	O
stood	O
for	O
CFRAD	O
software	O
(	O
Cisco	O
Frame	B-Protocol
Relay	I-Protocol
Access	O
Device	O
)	O
,	O
and	O
the	O
'	O
LF	O
 '	O
stood	O
for	O
LAN	O
FRAD	O
(	O
Local	O
Area	O
Network	O
Frame	B-Protocol
Relay	I-Protocol
Access	O
Device	O
–	O
i.e.	O
</s>
<s>
Ethernet/Token	O
Ring	O
to	O
Frame	B-Protocol
Relay	I-Protocol
)	O
.	O
</s>
<s>
'	O
I	O
 '	O
referred	O
to	O
an	O
ISDN	B-Protocol
access	O
device	O
.	O
</s>
<s>
A	O
boot	O
ROM	B-Device
upgrade	O
may	O
be	O
needed	O
to	O
use	O
16MB	O
of	O
flash	O
.	O
</s>
<s>
The	O
2500	O
ran	O
its	O
IOS	B-Protocol
directly	O
from	O
flash	O
memory	O
.	O
</s>
<s>
An	O
erasable	O
,	O
programmable	O
read-only	B-Device
memory	I-Device
(	O
EPROM	O
)	O
of	O
2MB	O
in	O
size	O
was	O
used	O
to	O
permanently	O
store	O
the	O
startup	O
diagnostic	O
code	O
(	O
ROM	B-Device
Monitor	O
)	O
,	O
and	O
RxBoot	O
.	O
</s>
<s>
This	O
ROM	B-Device
was	O
held	O
in	O
2x	O
PLCC	O
sockets	O
and	O
was	O
user	O
upgradeable	O
.	O
</s>
<s>
2511	O
)	O
had	O
a	O
PCMCIA	B-Architecture
slot	O
installed	O
on	O
the	O
board	O
.	O
</s>
<s>
It	O
was	O
intended	O
that	O
Cisco	O
would	O
send	O
IOS	B-Protocol
updates	O
on	O
PCMCIA	B-Architecture
,	O
which	O
would	O
then	O
update	O
the	O
router	O
.	O
</s>
<s>
The	O
2500	O
series	O
ran	O
Cisco	B-Protocol
IOS	I-Protocol
(	O
Internetworking	O
Operating	O
System	O
)	O
.	O
</s>
<s>
The	O
initial	O
IOS	B-Protocol
release	O
for	O
this	O
model	O
was	O
11.0	O
,	O
and	O
the	O
final	O
release	O
was	O
12.2(4 )	O
T	O
or	O
12.3(26 )	O
.	O
</s>
<s>
The	O
BOOTROM	O
OS	O
did	O
not	O
support	O
Tokenring	B-Device
interfaces	O
,	O
making	O
software	O
upgrade	O
more	O
complex	O
.	O
</s>
<s>
uClinux	B-Application
is	O
a	O
free	O
software	O
project	O
that	O
allows	O
a	O
stripped	O
down	O
Linux	B-Application
installation	O
to	O
be	O
run	O
on	O
the	O
Cisco	B-Device
2500	I-Device
.	O
</s>
<s>
The	O
Cisco	B-Device
2500	I-Device
series	I-Device
was	O
introduced	O
in	O
1993	O
and	O
sold	O
until	O
2001	O
.	O
</s>
