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| a small one...
this ips are local or remote?
147.60.165.227 / 18
147.60.179.48 /19
fast answer please!!!
thanks
alex | |
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| quote:
Originally posted by Slinky
Fast answer, they are both local. I thought this looked familiar.
http://www.examnotes.net/forums/sho...?threadid=61953
yes, is local.
we had a complex subneting question on trasncender with more than 4 segments and 12 ip address, with different masks and gateways and tuff queestions that need several subneting calculations.... all our heads was BLOCKED!!! | |
| Slinky 2002-10-03, 2:56 pm |
| From my understanding there are no really complex subnetting questions on 70-216. I know the exact quesiton your talking about on Transcenders, and that think took me forever to figure out and I still got it wrong.  Still doesn't hurt to be prepared though. | |
| jeff_j_black 2002-10-03, 2:57 pm |
| Man, thats whack!
significant octet
x.x.165.x /18
10100101 address
11000000 mask
10000000 subnet
significant octet
x.x.179.x /19
10110011 address
11100000 mask
10100000 subnet
Anding out the subnet portion of the address makes it look as though they are not on the same subnet. But you can see where they could overlap. It's kinda like a supernetting question out of context. | |
| Slinky 2002-10-03, 3:43 pm |
| They are not on the same subnet, but as far as computer 1 sending a packet to computer 2 they are on the same subnet. Seems wierd, but trust me they are. | |
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| quote:
Originally posted by Slinky
Fast answer, they are both local. I thought this looked familiar.
http://www.examnotes.net/forums/sho...?threadid=61953
but i have some doubts regarding the diferent masks uses... i know that are local but i can`t take this on paper | |
| jeff_j_black 2002-10-03, 4:17 pm |
| Reading the other post clarified, as they are attached to the same interface on a router that has the mask /19 applied. | |
| Slinky 2002-10-03, 4:25 pm |
| quote:
Originally posted by cm2gj
but i have some doubts regarding the diferent masks uses... i know that are local but i can`t take this on paper
Like I said before, TCP/IP will use its OWN subnet mask to determine whether or not the destination host is local or not. It doesn't even know the other computers subnet mask, and it doesn't matter.
x.x.165.x /18
10100101 address
11000000 mask
10000000 subnet
significant octet
x.x.179.x /18
10110011 address
11000000 mask
10000000 subnet
Exact same subnet,147.60.128.0. The subnet right after that is 147.60.192.0. Both hosts of 147.60.165.x and 147.60.179.x are well within that subnet. | |
| jeff_j_black 2002-10-03, 4:34 pm |
| Good point Slinky! | |
| Slinky 2002-10-03, 4:41 pm |
| And just for kicks lets pretend that computer 2 wants to send a packet to computer 1.
significant octet
x.x.165.x /19
10100101 address
11100000 mask
10100000 subnet
significant octet
x.x.179.x /19
10110011 address
11100000 mask
10100000 subnet
Now from computer 2s perspective they are both on 147.60.160.0 subnet. The next subnet is 147.60.192.0. Both are still local, but the extracted network IDs relative to each computer are different. | |
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| quote:
Originally posted by jeff_j_black
Reading the other post clarified, as they are attached to the same interface on a router that has the mask /19 applied.
weird!!! | |
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| quote:
Originally posted by Slinky
Like I said before, TCP/IP will use its OWN subnet mask to determine whether or not the destination host is local or not. It doesn't even know the other computers subnet mask, and it doesn't matter.
x.x.165.x /18
10100101 address
11000000 mask
10000000 subnet
significant octet
x.x.179.x /18
10110011 address
11000000 mask
10000000 subnet
Exact same subnet,147.60.128.0. The subnet right after that is 147.60.192.0. Both hosts of 147.60.165.x and 147.60.179.x are well within that subnet.
why you use subnet 18 and 18?.... one use 18 and the other 19.... or what is your point? | |
| Slinky 2002-10-03, 5:25 pm |
| When computer 1
(147.60.165.227 mask 255.255.192.0) wants to send a packet to 147.60.179.48 it has no clue what the subnet mask is for the remote computer. All it knows is that it has a destination address and its own subnet mask to determine whether or not the other computer is local. So it ANDs 147.60.179.48 with 255.255.192.0 and it sees 147.60.128.0 which means its local. | |
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| quote:
Originally posted by Slinky
When computer 1
(147.60.165.227 mask 255.255.192.0) wants to send a packet to 147.60.179.48 it has no clue what the subnet mask is for the remote computer. All it knows is that it has a destination address and its own subnet mask to determine whether or not the other computer is local. So it ANDs 147.60.179.48 with 255.255.192.0 and it sees 147.60.128.0 which means its local.
i understand now..... |
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