The information and data that is most precious, confidential and
important to you will almost certainly be on your home PC or laptop:
it is thus critically important that you secure these assets. Take this
advice: Never forget the obvious: computer thefts (particularly of laptops)
are prevalent, so exercise care with these valuable pieces
of equipment. The thief may be only interesting in the hardware
itself, not the contents of it – but this is little consolation to you
when you lose all of your personal files.
If you work at home for an organization ensure that you are
aware of, and comply with, any policies and procedures that they
have in relation to IT equipment and software in remote sites.
You should also check their policies and procedures on the storing
of their confidential information on home computers.
Install anti-virus software and ensure that it is kept continually
up to date (see the Web directory of this book for excellent free
programs for personal use).
Back up your data regularly and then keep the backup in a
separate secure place.
Install a firewall and then ensure that it is kept continually up to
date (again, see the Web directory of this book for excellent free
programs for personal use).
Use a BIOS password and a screen saver password to prevent
unauthorized access to your confidential information.
Don’t open unknown e-mail attachments – various viruses have
been distributed in this way, and no doubt will be in the future.
Do not use or distribute programs when their origins are unknown
to you.
Make sure that all your applications – particularly your application
system – are kept up to date with the latest patches (easier
said than done, I know!).
If possible, when not in use, turn your computer off and/or
disconnect it from the network and/or Internet. If you are not
on the Internet, or your computer is turned off totally, no intruder
can gain access to it.
Make certain that you have a boot disk or recovery disk, so if
you suffer a catastrophic failure then with this and your backup
disc you can start again.
Change passwords on Internet sites frequently (very few Web
sites request you to do this as a matter of course once you have
signed up with them). Don’t share your passwords with coworkers,
friends or even family – this could have horrendous
consequences if, as an example, money is removed from your
online bank account.
Be careful about giving your credit card details over the Internet
– unless you know who you are dealing with you could be
sending your details straight to a fraudster or transmitting them
across the ether with no security. Only give your credit card
details to a site that uses encryption.
If your system is the main server which communicates with the external untrusted network called the Internet, or even if you simply use your linux box to connect to your ISP and surf the net through PPP, then you should definitely think about installing a firewall on your system.
The preferable and the best option in this case is to install a commercial firewall. However, this option is not always possible and is more often than not unnecesarry. Buying, installing and configuring a good commercial firewall is not only expensive but most beginners find it pretty formidable. OK, I do not want to go through the hassle of a commercial firewall, what do I do? Well, 'ipchains' hold the key for you.
The Firewalling code in the Linux Kernel chnaged considerably after the release of Kernel 2.2. Since then, a lot of new utilites and features have been added. Amongst these improvements, is a kewl feature called 'ipchains', which is primariarly used for configuring the firewalling rules and other such related details.
Anyway, in this manual, we will learn about how to use ipchains to configure a transparent proxy on your linux box. So what exactly is a transparent proxy?
Well, a transparent proxy is basically something which fools the client (who connect to the server running the transparent proxy) into believing that they are directly connected to the web server (and not through a proxy.). OK, I am sorry, that is not exactly the correct way to describe it. ;-) Read on for a better description.
Well, a transparent proxy works in the following manner: It listens to a specific port (like the HTTP port i.e. 80) for any connections. As soon as it gets a request for a connection (in this case a HTTP request for a file.) then it redirects the user i.e. connection to another port on the same machine. Now this new port to which the connection is transferred is actually running a Proxy.
So, in affect what happens is, the client i.e. the user who connects to the server where the transparent proxy installed, assumes that it is directly connected and is communicating with the HTTP daemon. However, the truth of the matter is that all communication is being carried out via the proxy running on the server. All this would be clearer when you see the below picture of what happens:
Client --------> Server(Port 80 or HTTP)
The rules of the ipchains transfers client to the port where the proxy is running. So, now the communication takes place in the following manner:
Client --------> Server(Port of Proxy) --------> Server (Port 80 or HTTP)
So, the connection to Port 80 is indirect, however the client has little idea about it.
Now, that you know the working of transparent proxies, let us get down to configuring them on your machine. However, before we get down to the actual process, you need to check whether this is possible on you system or not. Simply look for the file:
/proct/net/ip_fwchains
If you have this file, then well and good, else you will have to recompile your Kernel. However, I am sure almost 98% of you would definitely have this file.
NOTE: In this case, we will be transferring all connections from Port 80 to Port 8080 where Squid runs by default. You could always transfer connections to any proxy port of your choice, by changing the revelant parts. I have taken up Squid, as it is the most common one.
Firstly, in order to transfer all connections from Port 80 to Port 8080, add the following lines to your startup script, so that they are executed each time you boot up.
Note: The server IP is xxx.xx.xx.xx
ipchains -A input -p TCP -d 127.0.0.1/32 www-j ACCEPT
ipchains -A input -p TCP -d xxx.xx.xx.xx/32 www-j ACCEPT
ipchains -A input -p TCP -d 0/0 www-j REDIRECT 8080
NOTE: If you are using ipfwadm, then add the following lines to the startup script:
ipfwadm -I -a-a -P tcp-s any/0 -D 127.0.0.1
ipfwadm -I -a-a -P tcp-s any/0 -D xxx.xx.xx.xx
ipfwadm -I -a-a -P tcp-s any/0 -D any/0 80 -r 8080
Once this is done, then configure Squid by following the below process. Please note that you need atleast Squid 2.x to be able to make use of Transparent Proxies. Anyway, to configure Squid, edit the, /etc/squid/squid.conf file and make the following changes:
httpd_accel_host virtual
httpd_accel_port 80
httpd_accel_with_proxy on
httpd_accel_uses_host_header on
Then,restart Squid by typing:
/etc/rc.d/init.d/squid.init restart
Voila, your transparent proxy is configured and running!!! Anyway, have fun and watch out for updated versions of this manual.
Getting the Internet Protocol or the IP Address of a remote system is said to the most important step in hacking of a system. Sometimes, however we get an IP in order to get more information on someone or some host. But, how can an IP Address be used to get more information on the location etc of a system? Well, this post is aimed at answering just this question.
Actually, the IP address (Actually the entire TCP/IP Protocol) is structured or designed such that one cannot tell as to in which country a system having the given IP is situated, by simply looking at it. An IP Address has no fields, which tell you the country in which the computer using it resides in. So, all myths like ‘The Second or the third field of an IP stands for the country in which the system using it resides’ are definitely false and untrue.
However, yes sometimes one can guess or deduce as to in which country and even in which city the system using an IP resides in, by simply looking at the first three fields of the IP. Let us take an example to understand what I mean to say by this. Now, before I move on the example, let us understand how exactly IP Addresses are awarded to you.
Firstly, your ISP registers at the central authority and gets a particular range of IP addresses between which the various customers (people who dial into their servers) can be awarded IP addresses. Most ISP’s are given a Class C network Address. A class C Network address contains a 24-bit Network Prefix (the first three fields) and an 8-bit Host number (the last field). It is referred to as "24's" and is commonly used by most ISP's.
Like in the real world, everyone has got an individual Home Address or telephone number so that, that particular individual can be contacted on that number or address, similarly all computers connected to the
Internet are given a unique Internet Protocol or IP address which can be used to contact that particular computer. In geek language an IP address would be a decimal notation that divides the 32- bit Internet addresses (IP) into four 8-bit fields.
Does the IP address give me some information or do the numbers stand for anything?
Let take the example of the following IP address: 202.144.49.110 Now the first part, the numbers before the first decimal i.e. 209 is the Network number or the Network Prefix.. This means that it identifies the number of the network in which the host is. The second part i.e. 144 is the Host Number that is it identifies the number of the host within the Network. This means that in the same Network, the network number is same. In order to provide flexibility in the size of the Network, here are different classes of IP addresses:
Address Class Dotted Decimal Notation Ranges
Class A ( /8 Prefixes) 1.xxx.xxx.xxx through 126.xxx.xxx.xxx
Class B ( /16 Prefixes) 128.0.xxx.xxx through 191.255.xxx.xxx
Class C ( /24 Prefixes) 192.0.0.xxx through 223.255.255.xxx
The various classes will be clearer after reading the next few lines.
Each Class A Network Address contains a 8 bit Network Prefix followed by a 24-bit host number. They are considered to be primitive. They are referred to as "/8''s" or just "8's" as they have an 8-bit Network prefix.
In a Class B Network Address there is a 16 bit Network Prefix followed by a 16-bit Host number. It is referred to as "16's".
A class C Network address contains a 24-bit Network Prefix and a 8 bit Host number. It is referred to as
"24's" and is commonly used by most ISP's.
Due to the growing size of the Internet the Network Administrators faced many problems. The Internet routing tables were beginning to grow and now the administrators had to request another network number from the Internet before a new network could be installed at their site. This is where sub-netting came in.
Now if your ISP is a big one and if it provides you with dynamic IP addresses then you will most probably see that whenever you log on to the net, your IP address will have the same first 24 bits and only the last 8 bits will keep changing. This is due to the fact that when sub-netting comes in then the IP Addresses structure becomes:
xxx.xxx.zzz.yyy
where the first 2 parts are Network Prefix numbers and the zzz is the Subnet number and the yyy is the host number. So you are always connected to the same Subnet within the same Network. As a result the first 3 parts will remain the same and only the last part i.e. yyy is variable.
For Example, if say an ISP xyz is given the IP: 203.98.12.xx Network address then you can be awarded any IP, whose first three fields are 203.98.12. Get it?
So, basically this means that each ISP has a particular range in which to allocate all its subscribers. Or in other words, all subscribers or all people connected to the internet using the same ISP, will have to be in this range. This in effect would mean that all people using the same ISP are likely to have the same first three fields of their IP Addresses.
This means that if you have done a lot of (By this I really mean a lot) of research, then you could figure out which ISP a person is using by simply looking at his IP. The ISP name could then be used to figure out the city and the country of the person. Right? Let me take an example to stress as to how cumbersome but easy (once the research is done) the above method can be.
In my country, say there are three main ISP’s:
ISP Name Network Address Allotted
ISP I 203.94.47.xx
ISP II 202.92.12.xx
ISP III 203.91.35.xx
Now, if I get to know the IP of an e-pal of mine, and it reads: 203.91.35.12, then I can pretty easily figure out that he uses ISP III to connect to the internet. Right? You might say that any idiot would be able to do this. Well, yes and no. You see, the above method of finding out the ISP of a person was successful only because we already had the ISP and Network Address Allotted list with us. So, what my point is, that the above method can be successful only after a lot of research and experimentation. And, I do think such research can be helpful sometimes.
Also, this would not work, if you take it all on in larger scale. What if the IP that you have belongs to someone living in a remote igloo in the North Pole? You could not possibly get the Network Addresses of all the ISP’s in the world, could you?
NOTE: In the above case, you also get to know the city of the system using the given IP, as most ISP’s use different network addresses in different cities. Also, some ISP’s are operational in a single city.
So, is there a better method of getting the location of an IP? Yes, Reverse DNS lookups hold the key.
Just as DNS lookup converts the hostname into IP address, a Reverse DNS Lookup converts the IP address of a host to the hostname. By hostname, what I mean to say is that it given us the name of the remote system in alphabets and numbers and periods. For Example, mail2.bol.net.in would be a hostname, while 203.45.67.98 would not be a hostname.
The popular and wonderful Unix utility ‘nslookup’ can be used for performing Reverse DNS lookups.
So, if you using a *nix box or if you have access to a shell account, then the first this to do is to locate where the nslookup command is hidden by issuing the following command:
' whereis nslookup '.
Once you locate where the utility is hidden, you could easily use it to perform both normal and reverse DNS lookups. As this is not a post on using the ‘nslookup’ command, I will simply giving a basic relevant outline. In order to get a more detailed description of how this works or how to use it, read the *nix man pages or the documentation.
We can use ‘nslookup’ to perform a reverse DNS lookup by mentioning the IP of the host at the prompt.
For Example,
$>nslookup IP Address
Note: The below IP’s and corresponding hostnames have been made up. They may not actually exist.
Let us say, that above, instead of IP Address, we type 203.94.12.01 (which would be the IP I want to trace.).
$>nslookup 203.94.12.01
Then, you would receive a response similar to: mail2.bol.net.in
Now, if you carefully look at the hostname that the Reverse DNS lookup, gave us, then the last part reveals the country in which system resides in. You see, the ‘.in’ part signifies that the system is located in India. All countries have been allotted country codes, which more often than not are the last part of the hostnames of the systems located in that country. This method can also be used to figure out as to which country a person lives in, if you know his email address. For Example, if a person has an email address ending in .ph then he probably lives in Philippines and if it ends in .il then he lives in Israel and so on. Some common country codes are:
Country Code
Australia .au
Indonesia .id
India .in
Japan .jp
Israel .il
Britain .uk
For a complete list of country codes, visit:
http://www.alldomains.com
http://www.iana.org/domain-names.html
Windows users can perform Reverse DNS queries by downloading an utility called Samspade from: www.samspade.com
Another method of getting the exact geographical location of a system on the globe is by making use of the WHOIS database. The WHOIS database is basically the main database, which contains a variety of information like contact details, name etc on the person who owns a particular domain name. So, basically what one does in a WHOIS query, is supply the WHOIS service with the hostname on which he wants more information. The WHOIS service then replies with the information stored in its database.
This method can be used to get some pretty accurate information on a particular IP or hostname; however, it is probably of no use if you are trying to point out the exact location of a dynamic IP. But, again this can be used to get atleast the city in which the ISP used by the victim is situated.
You can carry out WHOIS queries at: http://www.allwhois.com
You could also directly enter the following in the location bar of your Browser and perform a WHOIS enquiry.
Enter the following in the location bar of your browser:
http://205.177.25.9/cgi-bin/whois?abc.com
Note: Replace abc.com with the domain name on which you want to perform a WHOIS query.
This method cannot be used to get the contact address of a person, if the IP that you use to trace him, belongs to his ISP. So, either you need to know the domain name (which is registered on his name) or have to remain satisfied knowing only the city (and ISP) used by the person.
Say, the victim has registered a domain name and you want to use it to find out the city in which he resides. Now, one thing to remember in this case is that, if the victim has registered the domain name using any of the various free .com registration services like Namezero.com etc, then the domain name would probably be registered on the company’s name and not the victim’s name. So, a WHOIS query will give information on the ISP and not the victim.
Yet another and probably the second most efficient method (after Reverse DNS queries) of tracing an IP to its exact geographical location, is to carry out a ‘traceroute’ on it. The ‘tracert’ or ‘traceroute’ commands give you the names or IP’s of the routers through which it passes, before reaching the destination. Windows users can perform a trace of an IP, by typing the following at the command line prompt:
C:\windows>tracert IP or Hostname
For more information about the usage and syntax of this command, type: ‘tracert’ at the command prompt.
Anyway, now let us see what is the result, when I do a tracert on my IP. Remember I live in New Delhi which is a city in India. Watch the names of the hostnames closely, as you will find that they reveal the cities through which the packet passes.
C:\windows>tracert 203.94.12.54
Tracing route to 203.94.12.54 over a maximum of 30 hops
1 abc.netzero.com (232.61.41.251) 2 ms 1 ms 1 ms
2 xyz.Netzero.com (232.61.41.0) 5 ms 5 ms 5 ms
3 232.61.41.10 (232.61.41.251) 9 ms 11 ms 13 ms
4 we21.spectranet.com (196.01.83.12) 535 ms 549 ms 513 ms
5 isp.net.ny (196.23.0.0) 562 ms 596 ms 600 ms
6 196.23.0.25 (196.23.0.25) 1195 ms1204 ms
7 backbone.isp.ny (198.87.12.11) 1208 ms1216 ms1233 ms
8 asianet.com (202.12.32.10) 1210 ms1239 ms1211 ms
9 south.asinet.com (202.10.10.10) 1069 ms1087 ms1122 ms
10 backbone.vsnl.net.in (203.98.46.01) 1064 ms1109 ms1061 ms
11 newdelhi-01.backbone.vsnl.net.in (203.102.46.01) 1185 ms1146 ms1203 ms
12 newdelhi-00.backbone.vsnl.net.in (203.102.46.02) ms1159 ms1073 ms
13 mtnl.net.in (203.194.56.00) 1052 ms 642 ms 658 ms
So, the above shows us that the route taken by a data to reach the supplied IP is somewhat like this:
Netzero (ISP from which the data is sent) ---à Spectranet (A Backbone Provider) -----à New York ISP ---àNew York Backbone -à Asia --à South Asia -à India Backbone --à New Delhi Backbone --à Another router in New Delhi Backbone ---à New Delhi ISP.
So, basically this tracert does reveal my real location, which is: New Delhi, India, South Asia. Get it?
Sometimes, doing a ‘tracert’ on an IP, does not give useful information. You see in the above example, the hostnames returned revealed the city or country in which the system is located. Although, more often than not, you will get such helpful hostnames, sometimes the hostnames returned are very vague and unhelpful.
So what do you do then? Well, fret not. Simply do the below procedure.
Let us say that the trace ends at the hostname abc.com. This is very vague and gives absolutely no clue as to where the system is located. However, what you could do is, launch your browser and visit: http://www.abc.com Now, abc.com is probably an ISP and an ISP, will definitely give its location and the cities in which it operates. So, you could still have a good chance of learning the definite city of the victim.
A very interesting utility is the VisualRoute utility, (http://www.visualroute.com) which traces a hostname or IP and shows the path taken by the packet to reach the destination on a world map. It is very useful and reveals some excellent information. However, it sometimes does tend to be inaccurate.
Well, this basically brings us to the end of this post. Before I sign off, I would like to make it clear that it extremely difficult and surprising if someone is able to get the exact contact address of a person by simply knowing his IP. (Without taking help or breaking into the person’s ISP) Anyway, hope you liked this post. Goodbye.
Now days, almost all networks have firewalls installed to protect them from the dangers of the un-trusted outside world of the Internet. When firewalls first came to the scene, they were nowhere near good enough to protect the Network completely. However, with the passage of time, the quality of firewalls has increased to such a level that the present day firewall systems make the internal trusted network almost 100% safe.
They can easily be configured to allow only certain kinds of data to pass through and even can be used to set which ports can be accessed from the un-trusted network (Internet) and which ports are accessible from the internal trusted network. Some good ones also scan all attachments going in and out for viruses and ensure that no confidential data is going out of the company. The present day firewalls have really made life quite easier for the system administrating by giving more than a little protection from the Outside world. However, one area where the firewalls falter is if the attach is from within the trusted internal network or in other words, the attacker is doing something wrong, something which he is not supposed to do from within the network and not through the Internet.
Say for example, you have a well configured; firewall installed at your company’s main server and it scans all incoming email attachments for viruses. Now, if you get a virus attach from outside the internal trusted network and though the Internet, then normally the firewall will either delete or warn you about it. However, if the virus coder, is working for you and is within the internal trusted network, then a firewall would not be able to do anything about it and the virus will spread quite easily.
NOTE: The above is just an example taken to ensure that you understand.
So, now, I hope you realize that only a Firewall is not sufficient for a network and it also requires something for attacks from internal systems.
This is where the Kerberos comes in. Kerberos is a network authentication protocol, which provides for the verification of identities within a heterogeneous distributed networked environment. It is the de facto standard for authentication, which gets it name from the three-headed dog in Greek Mythology.
For complete reference and details about Kerberos authentication protocol, refer to the RFC 1510
Now, within an internal network, the greatest danger lies in the fact that anyone can easily pick up or sniff out confidential data like company plans, passwords and even credit card numbers while this data is being transferred from one system to another within the same network.
Let us take an example, to understand better. Say, you are on a client, which is connected to the main server, which provides services to all clients connected to it. Now, when you connect to the server to check your mail, then your email client sends your Username and Password to the internal network server, so that you can be authenticated. You may say that this is pretty much safe and how can it possible harm me? Well, you are wrong. Now, when your machine sends your Username and Password to the server, then this information does not reach the destination server directly. The data has to pass through other machines and sometimes if your network is large, then even through other servers before it reaches the destination. Now, anyone having access to those systems through which your data passes through, can easily sniff out your data and in this case can find out your Username and Password, using which he can check your mail.
To solve all the above problems (and many more) there is the Kerberos. The Kerberos not only ensures that no one sniffs data out, but also ensures the integrity of the client and server to prevent impersonation. This basically means that it ensures that no one can fool the server into thinking that it is some other system.
Now, to understand how exactly, Kerberos proves to be as good as it is, let us learn how the Kerberos protocol works.
The most popular Network Authentication providing software, Kerberos is constituted of 3 main parts or sections-:
1.) The Authentication Server or AS
2.) The Ticket Granting Server or TGS
3.) The Actual Encryption process or algorithm
In a Network with Kerberos installed or enabled, the Authentication Server or the AS acts as the head or the central unit, which ensures the authenticity of the client and server and also prevents data sniffing.
One good thing about the Kerberos Authentication system is that is a dual-authentication system, which means that it not allows the server to verify the identity of the client but also vise-a-versa.
The Authentication Server acts as the secretary of both the client and the server. The client and the server in order to communicate with each other, have to have a connection with the AS. (The AS verifies identities of both the client and the server.) Only once the AS has verified the authenticity of both the client and the server, can they start to communicate with each other.
Kerberos: The Working
So when does Kerberos jump in? Well, as soon as you want to login and type in your Username in the space provided. As soon as you type the confidential information, the Kerberos sends it to the Authentication Server or the AS. Then, the AS replies to the client with the session key and something called the Ticket Granting Ticket. Both the session key and the Ticket Granting ticket are encrypted by the user’s key. Now, before we go on, I think there is need to explain certain things involved in the above process.
Now, you must remember that the client and the Authentication Server and the client share an encryption key, which is used to encrypt data. This encrypted data is understandable (de-cryptable) by only the AS and the client. This encryption key is generated from the User’s Password. This means that, passing the User’s password through a certain predefined formula derives this encryption key. Similarly all Servers, which provide services to clients, share an encryption key with the AS.
So this system of client-AS and server-AS encryption keys ensures that no one else can sniff the data.
Now, we come to the Ticket Granting Ticket, which is sent along with the session key[The session key is sent to the client by the AS, so that the client can start to communicate with the Ticket Granting Server or TGS.] to the client by the AS. A ticket is nothing but a certificate of authenticity given to the client by the AS to prevent impersonation. The ticket is readable only by the client system for which it is meant to be and the AS. The Ticket Granting Ticket also makes the Kerberos system efficient as it removes the need of repeating the initial process again and again.
Now, once the client receives the session key and the TG Ticket, it derives the client’s key from the user’s password and tries to use this generated key to decrypt the TG Ticket and the Ticket Granting Server key or the TGS key. If the client is able to decrypt these two, then the password is correct else wrong.
Now, say you want to then, use the POP services of the mail server to read your mail, then what happens is that, the client sends a request to The Ticket Granting Server or TGS. The client encrypts important network information and details about the request with the TGS key and sends this encrypted data to it.
If this is found to be valid, then TGS issues a ticket to the client which contains the following-:
1.) Username
2.) Address
3.) Service Name
4.) Lifespan
5.) Timestamp
6.) Other Session Key details.
An important thing to note here is that, for communication between the client and the server to actually take place, they should share the same key.
The TGS generates two copies of this session key, one encrypted with TGS key for the client and the other with application server key. Using the TGS key, the client then, decrypts the session key meant for it, and the session key for the application server is sent to the destination.
When the server receives the session key, and once it is decrypted, it knows that this particular client is trying to contact it. The server too has a procedure to ensure the authenticity of the client. It sends a random number in plain text to the client. The client then decrypts it with the session key (which they both have in common) and sends it back to the server. On receiving this encrypted text, it can ensure that the client is not an impersonator, as some other client cannot perform the same encryption.
Kerberos ensures that Sniffing out data is not that easy, as transfer of all data, even the Keys, is done in encrypted form. The encryption technique used by Kerberos is Data Encryption Algorithm or DES.
However, there is still a slight hole in the Kerberos system. You see, during the time when the Password is sent to the AS in the first step, it travels through the Network in unencrypted form. This is one time, when the Kerberos system can be exploited.
Windows 2000 is I think the first Operating System, which uses Kerberos as the standard authentication method. Anyway, now that you know how exactly, the Kerberos Authentication System works, let us move on to how to find out if your ISP is running it or not? Also, I highly recommend reading the RFC 1510. This is for those who want even the tiniest of details about this system.
How do I find out if my ISP is running Kerberos?
NOTE: In this section, I am assuming that you have enabled the Bring Up the Post Dial Up Screen option.
Well, the router of your ISP to which you initially connect to, holds the key. Almost all of you must have seen the Post Dial Up Screen, which comes up, where you have to enter your Username and Password. Now, this Post Dial Up Screen is actually your ISP’s router prompt. There is a secret (Well, not exactly secret) router command, which will let you find out if your ISP has implemented the Kerberos protocol.
The following is a log which contains my comments of what I did to find out whether my ISP is using Kerberos or not.
User Access Verification
Username: Nihaar
Password:
NP-NAS3>help
Help may be requested at any point in a command by entering
A question mark '?'. If nothing matches, the help list will
be empty and you must backup until entering a '?' shows the
available options.
Two styles of help are provided:
1. Full help is available when you are ready to enter a
command argument (e.g. 'show ?') and describes each possible
argument.
2. Partial help is provided when an abbreviated argument is entered
and you want to know what arguments match the input
(e.g. 'show pr?'.)
[Nihaar: help is not the right command, let me try ‘?’]
NP-NAS3>?
Exec commands:
access-enable Create a temporary Access-List entry
access-profile Apply user-profile to interface
attach attach to system component
clear Reset functions
connect Open a terminal connection
disable Turn off privileged commands
disconnect Disconnect an existing network connection
enable Turn on privileged commands
exit Exit from the EXEC
help Description of the interactive help system
lat Open a lat connection
lock Lock the terminal
login Log in as a particular user
logout Exit from the EXEC
mrinfo Request neighbor and version information from a multicast
router
mstat Show statistics after multiple multicast traceroutes
mtrace Trace reverse multicast path from destination to source
name-connection Name an existing network connection
pad Open a X.29 PAD connection
ping Send echo messages
ppp Start IETF Point-to-Point Protocol (PPP)
resume Res
According to the February 2008 issue of Business Trends the semi-conductor industry is looking to decrease its spending by 9.9%. Industry experts say this is due to account for the over supply of memory.
Although spending will slip overall for the year experts believe that it will pick back up towards the end of this year setting up what could be a solid 2009.
The industry was fortunate enough to enjoy increases in the 20% range in 2006 but saw the trend to slow throughout 2007 only increasing 6.8% to $44 billion dollars.
Also according to Business Trends, "In 2008, all major segments of the equipment market to see lower spending, particularly areas that are heavily exposed to the DRAM acctor."
Also fear of a looming U.S. recession has lead many top execs at a lot of these companies to slow its spending.
Gartner claims that he, "sees a weak first half as DRAM companies slow down investments to get supply and demand balance under control, more than offsetting increased spending fo NAND flash. But foundries pushing to the next technology node should lead a rebound in2H08, along with logic investments."
In 2007 the total semi-conductor capital spending hit $59.09 billion dollars and will slip to $51.30 billion dollars. However experts predict that those figures will increase in 2009 to $55.72 billion and increase again in 2010 $63.25 billion.
There is no question that a slowing U.S. economy has a strong affect on the semi-conductor industry, however experts in the field agree, that they will rebound fine and by the end o 2012 everything will be back to normal heading in a positive direction.
