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New Member

Strange!! network address pingable

I have a 3640 connected by frame relay. all the sub interface are point-to-point and have 30 bits subnet on the WAN interfaces.

How come that I can ping the network IP address e.g

router1 s0/0.16 -->10.4.255.5 255.255.255.252

s0.17 -->10.4.255.9 255.255.255.252

router2 s0/0.16 -->10.4.255.6 255.255.255.252

router3 S0/0.17-->10.4.255.10 255.255.255.252

The router is configured with static routes only.

when I ping 10.4.255.4 & .8 (which is the network address), how come I get a response. The pings are all successful from the router & workstation. I checked the 'S ARP' and it doesn't appear there.

could someone please explain why is it like this.

many thanks in advance.

  • Other Network Infrastructure Subjects
3 REPLIES
hdt
New Member

Re: Strange!! network address pingable

Hi,

I think you have enable Ip subnet-zero command. With this command you can use the network-adres of a subnet you created.

New Member

Re: Strange!! network address pingable

yes you are right with IP subnet-zero and the concept of this is to allow you to use the '0' and '1' subnet portion of the address. I am still puzzeled why I can ping the network address even no device is using that IP address.

what do you reckon mate?

Gold

Re: Strange!! network address pingable

Because this is a broadcast address on the segment--a long time ago, in a galaxy far away, people used to use the all 0's network address as the broadcast, and the all 1's wasn't used. Then along came cidr, and the world was changed for the better (theoretically). Now, we keep the concept of the all 0's network address as a broadcast, although very few hosts use it.

And this has been your trivia lesson for the night.

:-)

Russ

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