ICMP – Destination Unreachable Message

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This ICMP message is quite interesting, because it doesn’t actually contain one message, but six! This means that the ICMP Destination unreachable further breaks down into 6 different messages.

We will be looking at them all and analyzing a few of them to help you get the idea.

The ICMP Destination Unreachable Message

Code Value in ICMP Header	Message
0	Net Unreachable
1	Host Unreachable
2	Protocol Unreachable
3	Port Unreachable
4	Fragmentation Needed and DF set
5	Source Route Failed

Note: Codes 0, 1, 4 and 5 may be received from a gateway.
Codes 2 and 3 may be received from a host

To make sure you don’t get confused, keep one thing in mind: The ICMP Destination unreachable is a generic ICMP message, the different code values or messages which are part of it are there to clarify the type of "Destination unreachable" message was received. It goes something like this: ICMP Destination <Code value or message> unreachable.

The ICMP – Destination net unreachable message is one which a user would usually get from the gateway when it doesn’t know how to get to a particular network.

The ICMP – Destination host unreachable message is one which a user would usually get from the remote gateway when the destination host is unreachable.

If, in the destination host, the IP module cannot deliver the packet because the indicated protocol module or process port is not active, the destination host may send an ICMP destination protocol / port unreachable message to the source host.

In another case, when a packet received must be fragmented to be forwarded by a gateway but the "Don’t Fragment" flag (DF) is on, the gateway must discard the packet and send anICMP destination fragmentation needed and DF set unreachable message to the source host.

These ICMP messages are most useful when trying to troubleshoot a network. You can check to see if all routers and gateways are configured properly and have their routing tables updated and synchronised.

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Human Clone, Sounds Good. But, is it really good?

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Human Clone

When your laptop gets old and really slow, you try to wipe out the unnecessary stuffs, scan for viruses and try to harden the operating system in the hope that it can be used as a brand new box instead of wasting more $$ and buying a new one. Buying a new one is good, but it’s a pain if you have to re-install each and every licensed software’s on it. But, once you realize that you have to get rid of your old laptop and that can be used only as a paper weight, then either you have to throw the sucker out of window or you have to use it as I said as a real paper weight. 🙂 Now, once you buy a new laptop, you have this thing at the back of your mind that you will only use licensed software’s and no more hacked stuffs or torrent downloads.

This is what exactly happens when you get old and you wish your internal organs function the same way when you were young, but alas! you are getting old and soon will be wiped out from the earth. That’s how the life is. All that’s born has to die some or the other day. But, look at the technology, just like the dual processors in computers, scientists have come up with human clone. You can make an exact copy of yourself (a young you!!); meaning the exact human appearance. But, what about the internal organs? It’s all new, fresh and young. So, it’s like a brand new laptop with all new processors ready to roll. But, just like the computers when it’s new, the cloned human won’t have any data, ie. he won’t know who he is or who she is, because we didn’t feed him or copy the data. I am not sure if you can copy the data in you to the new cloned human just like you transfer data from your old to the new computer. Personally, I don’t think it’s possible since all the data or information that we have is what we leaned bit by bit from our surroundings and how we were brought up by our parents. To transfer this data to the new cloned body is highly impossible unless the scientist come up with something really unnatural. But, do you think it’s really good to clone a human? If you ask me, i would be willing to. I, Sojesh, will be kind of immortal. Wow!!!! Isn’t it something? 🙂 And I will educate the new clone all that I know and give him his identity. Then he becomes I, but no matter, what you feed the new guy with, he wont become exactly you. But, that won’t really matter. Problem comes when underworld guys start making their clone. You can never say if the person you caught or behind bars is the real person who did the crime. Or you make many clones of yours and use them for various illegal stuffs and you are never caught. So, do you think we should really start cloning humans? Humans are too curious that they will try out anything that comes to them and when it happens, they will try the real thing which could be real bad and might pose a real threat to the entire humanity and imbalance the natural habitat of entire living beings.

Wag More, Bark Less

Sometimes I think that most of the people speak about others too much, more of their negative quality than their positive once they see or which they try to ignore. Most of them does that, right?

I don’t know. May be it’s how the humans are.. Or should I say that’s how the females are? I am not kidding. I won’t say that it’s only females, but I am so damn sure that most of them have a thing for gossiping and making up stories on what according to me is such a silly thing. If you ask me how I would take the same thing, I would be happy to ignore the whole thing than poke my nose in somebody’s business or waste my time gossiping. But, I thing it’s a universal fact that people love gossiping about others on their negative side than what positive qualities they see in others. I am not criticizing anyone in particular, but just pointing out what i think is more in them. I think I should bark less and wag more.

The Unsaid

Sometimes what is left unsaid is as powerful if not more so than the words we do share. And while I hate when others do this, here it is. There is a lot I’m leaving unsaid right now. Before I face a barrage of opinions and feedback and other people’s thoughts, I need to make sure I’m clear on my own. I need the dust to settle. I need to breathe.

So I may not be saying a lot right now. But I’m here. And I’m living. And with each passing day the dust is settling a bit more and my breaths come clearer. When this all lifts for sure, I’ll have a lot to say. Don’t you worry.

But for now, I’m here. I’m quiet, but I’m here. Don’t give up on me.