<s>
Intelligent	B-Protocol
Resilient	I-Protocol
Framework	I-Protocol
(	O
IRF	O
)	O
is	O
a	O
proprietary	B-Application
software	I-Application
virtualization	B-General_Concept
technology	O
developed	O
by	O
H3C	O
(	O
3Com	O
)	O
.	O
</s>
<s>
Its	O
purpose	O
is	O
to	O
connect	O
multiple	O
network	B-Architecture
devices	O
through	O
physical	O
IRF	O
ports	O
and	O
perform	O
necessary	O
configurations	O
,	O
then	O
virtualize	B-General_Concept
the	O
devices	O
into	O
a	O
distributed	O
device	O
.	O
</s>
<s>
This	O
virtualization	B-General_Concept
technology	O
performs	O
the	O
unified	O
management	O
and	O
maintenance	O
of	O
multiple	O
devices	O
.	O
</s>
<s>
Simplified	O
topology	B-Architecture
and	O
streamlined	O
management	O
.	O
</s>
<s>
An	O
IRF	O
virtual	B-Application
device	I-Application
appears	O
as	O
a	O
node	B-Protocol
on	O
the	O
network	B-Architecture
.	O
</s>
<s>
You	O
can	O
log	O
into	O
it	O
by	O
connecting	O
to	O
any	O
port	O
of	O
any	O
member	O
to	O
manage	O
all	O
members	O
of	O
the	O
IRF	O
virtual	B-Application
device	I-Application
.	O
</s>
<s>
Simple	O
network	B-Architecture
operation	O
.	O
</s>
<s>
For	O
example	O
,	O
routing	O
protocols	O
calculate	O
the	O
routes	O
of	O
the	O
IRF	O
virtual	B-Application
device	I-Application
instead	O
of	O
calculating	O
the	O
routes	O
of	O
each	O
member	O
.	O
</s>
<s>
This	O
avoids	O
a	O
great	O
number	O
of	O
protocol	O
packet	O
exchanges	O
among	O
the	O
members	O
,	O
simplifies	O
network	B-Architecture
operation	O
,	O
and	O
shortens	O
the	O
convergence	O
time	O
during	O
network	B-Architecture
flapping	O
.	O
</s>
<s>
In	O
addition	O
,	O
this	O
advantage	O
of	O
the	O
IRF	O
technology	O
is	O
not	O
delivered	O
by	O
the	O
common	O
cluster	B-Architecture
technology	O
,	O
which	O
only	O
realizes	O
the	O
unified	O
management	O
of	O
devices	O
,	O
and	O
the	O
devices	O
in	O
a	O
cluster	B-Architecture
operate	O
as	O
independent	O
nodes	O
.	O
</s>
<s>
The	O
IRF	O
technology	O
creates	O
an	O
IRF	O
virtual	B-Application
device	I-Application
from	O
multiple	O
low-end	O
devices	O
,	O
and	O
thus	O
the	O
IRF	O
virtual	B-Application
device	I-Application
has	O
a	O
higher	O
port	O
density	O
and	O
bandwidth	O
and	O
costs	O
lower	O
than	O
using	O
high-end	O
devices	O
.	O
</s>
<s>
Powerful	O
network	B-Architecture
expansion	O
capability	O
.	O
</s>
<s>
By	O
adding	O
member	O
devices	O
,	O
the	O
number	O
of	O
IRF	O
ports	O
,	O
network	B-Architecture
bandwidth	O
,	O
and	O
processing	O
capability	O
of	O
the	O
IRF	O
virtual	B-Application
device	I-Application
can	O
be	O
easily	O
expanded	O
.	O
</s>
<s>
Users	O
only	O
need	O
to	O
add	O
new	O
devices	O
rather	O
than	O
replacing	O
the	O
original	O
ones	O
when	O
upgrading	O
a	O
network	B-Architecture
because	O
of	O
the	O
powerful	O
network	B-Architecture
expansion	O
capability	O
of	O
the	O
IRF	O
virtual	B-Application
device	I-Application
.	O
</s>
<s>
IRF	O
provides	O
both	O
link	O
and	O
node	B-Protocol
redundancy	O
.	O
</s>
<s>
An	O
IRF	O
virtual	B-Application
device	I-Application
comprises	O
multiple	O
member	O
devices	O
that	O
operate	O
in	O
1:N	O
redundancy	O
:	O
the	O
master	O
runs	O
,	O
manages	O
and	O
maintains	O
the	O
IRF	O
virtual	B-Application
device	I-Application
,	O
whereas	O
the	O
slaves	O
process	O
services	O
as	O
well	O
as	O
functioning	O
as	O
the	O
backups	O
.	O
</s>
<s>
As	O
soon	O
as	O
the	O
master	O
fails	O
,	O
the	O
IRF	O
virtual	B-Application
device	I-Application
immediately	O
elects	O
a	O
new	O
master	O
to	O
prevent	O
service	O
interruption	O
.	O
</s>
<s>
In	O
addition	O
,	O
you	O
can	O
aggregate	O
both	O
IRF	O
links	O
of	O
members	O
and	O
the	O
links	O
between	O
the	O
IRF	O
virtual	B-Application
device	I-Application
and	O
its	O
upper	O
or	O
lower	O
layer	O
devices	O
.	O
</s>
<s>
You	O
can	O
increase	O
the	O
bandwidth	O
and	O
processing	O
capability	O
of	O
an	O
IRF	O
virtual	B-Application
device	I-Application
simply	O
by	O
adding	O
member	O
devices	O
.	O
</s>
<s>
Each	O
member	O
device	O
has	O
its	O
own	O
CPU	B-Device
and	O
they	O
independently	O
process	O
and	O
forward	O
protocol	O
packets	O
.	O
</s>
<s>
IRF	O
provides	O
all	O
features	O
supported	O
by	O
a	O
switch	O
,	O
such	O
as	O
IPv4	B-Protocol
,	O
IPv6	B-Protocol
,	O
MPLS	B-Protocol
,	O
security	O
features	O
,	O
OAA	O
cards	O
,	O
high	O
availability	O
,	O
which	O
can	O
run	O
effectively	O
and	O
stably	O
on	O
the	O
IRF	O
virtual	B-Application
device	I-Application
,	O
and	O
thus	O
expands	O
the	O
application	O
of	O
IRF	O
virtual	B-Application
devices	I-Application
.	O
</s>
<s>
An	O
IRF	O
virtual	B-Application
device	I-Application
can	O
be	O
created	O
from	O
box-type	O
devices	O
or	O
chassis-type	O
distributed	O
devices	O
.	O
</s>
