It is now almost midnight, and I realize that the reason for this question
could be a temporarily black hole in my head, but here it is anyway.
Since we're talking about a directed broadcast address for a network - when
does a Cisco router actually use that address?
When I assign an IP address to any interface, that be ethernet, tokenring,
serial or loopback, the result I get from a SHOW IP INT always tells me that
the broadcast address for that network is 255.255.255.255.
Am I just being too tired, or what's going on here?
Thanks,
Ole
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Ole Drews Jensen
Systems Network Manager
CCNA, MCSE, MCP+I
RWR Enterprises, Inc.
[EMAIL PROTECTED]
http://www.RouterChief.com
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
NEED A JOB ???
http://www.oledrews.com/job
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-----Original Message-----
From: Leigh Anne Chisholm [mailto:[EMAIL PROTECTED]]
Sent: Tuesday, July 24, 2001 11:30 PM
To: [EMAIL PROTECTED]
Subject: RE: ccna challenge question [7:13565]
The term "classful" could have been thrown in for two reasons. 1, as you
suggest, is to lead the reader to think about "classful". Do they really
understand the concept? If they don't, they'd likely select a broadcast of
172.18.255.255. The other is that it may have been a leftover from a
similar question where the question was changed just enough so that the
phrase really didn't apply.
I guess the definitive answer about the CertificationZone question of the
week for last week would really be to find out who wrote the question, and
ask what their thinking was at the time. I just checked my files--it wasn't
one of mine so I can't say one way or the other...
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of
Guy Russell
Sent: Tuesday, July 24, 2001 8:33 PM
To: [EMAIL PROTECTED]
Subject: Re: ccna challenge question [7:13565]
Yes, I agree....
But why the bit about Classful. It seemed whoever wrote the question wanted
it to be an issue about the "Classful" idea.
Normally, I would fully agree, but if this was a Cisco test question,
especially since the way they word some questions, how would you answer...
I agree with both points!!!
But again take a look at the term classful. When do we see it...
Now lets break down the question...
Using Classful assumptions, what is the directed broadcast address for
172.18.2.0 with the mask of 255.255.254.0?
Now clearly, it says... Using classful assumptions....
At first glance it appears to be a simple subnetting question where we would
try to find the network and broadcast address. So in that case we would come
up with...
172.18.2.0 as the network ID and 172.18.3.255 as the broadcast...
But thats too easy... if we were sitting at a 100.00 test, we would have to
rethink...
Now, again if we were sitting at a CCNA test, we would see 2 correct answers
for either way we went. Cisco isnt like that... SO I personally would be
inclined to think its a test to see if we know the difference between
classless ans classful routing.
Again, only if this was an actual test question!!! If this was something
someone asked me off the top of my head, I would agree, but it is a
challenge question....
----- Original Message -----
From: "Leigh Anne Chisholm"
To:
Sent: Tuesday, July 24, 2001 7:10 PM
Subject: RE: ccna challenge question [7:13565]
> Classful addressing doesn't mean that routers do not look at the subnet
> mask. Au contraire! Routers ALWAYS are concerned with subnet mask
> information!
>
> Classful addressing just means that a router that receives a routing
update
> for a network for which it does not have a directly connected interface
will
> assume the standard classful subnet mask. In the case of a router that
does
> have a directly connected interface that is using a subnet mask that is
> borrowing bits from the host portion of the mask, it applies that mask to
> the advertised network information. Variable subnet masking (subnet masks
> of different lengths - /25, /26, /27 used in conjunction with the same
> network) is not supported.
>
>
> -- Leigh Anne
>
> At 05:48 PM 7/24/01, Guy Russell wrote:
> >Actually I disagree...
> >
> >Routers using Classful addresses, do not look at the subnet mask, nor do
> >they transmit the subnet mask...Since the term classful was used, we
would
> >obviously be talking about the routing protocol, so a broadcast would be
> >based only on the first octet to decide.
> >
> >Now a machine is not dependent on classful, it understands its own subnet
> >mask, and then the answer would be that... But the term Classful negates
> >that theory of it being a computer or other host...
> >
> >
> >
> >----- Original Message -----
> >From: Priscilla Oppenheimer
> >To:
> >Sent: Tuesday, July 24, 2001 5:28 PM
> >Subject: Re: ccna challenge question [7:13565]
> >
> >
> > > At 04:28 PM 7/24/01, Ed Moss wrote:
> > > >The key in the question is the word "classful".
> > >
> > > Classful doesn't mean it has to end on an 8-bit boundary.
> > >
> > > >This is a Class B address
> > > >with a 16 bit classful mask.
> > >
> > > It's not 16-bit. It says the mask is 255.255.254.0. That's 23 bits in
> the
> > > prefix (network) part.
> > >
> > > The answer is B. Put it in binary to understand it.....
> > >
> > > Priscilla
> > >
> > > >I would have to say the correct answer would
> > > >be 'C' 172.18.255.255.
> > > >Ed
> > > >
> > > > > Using classful assumptions, what is the directed broadcast address
> for
> > > > > 172.18.2.0 with the mask 255.255.254.0?
> > > > > a) 172.18.2.255
> > > > > b) 172.18.3.255
> > > > > c) 172.18.255.255
> > > > > d) 172.18.0.0
> > > >
> > > > > Answer
> > > > > b)
> > > ________________________
> > >
> > > Priscilla Oppenheimer
> > > http://www.priscilla.com
> ________________________
>
> Priscilla Oppenheimer
> http://www.priscilla.com
Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=13716&t=13565
--------------------------------------------------
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
