To NTFS or not to NTFS—that is the question. But unlike the deeper questions of life, this one isn't really all that hard to answer. For most users running Windows XP, NTFS is the obvious choice. It's more powerful and offers security advantages not found in the other file systems. But let's go over the differences among the files systems so we're all clear about the choice. There are essentially three different file systems available in Windows XP: FAT16, short for File Allocation Table, FAT32, and NTFS, short for NT File System.

FAT16

The FAT16 file system was introduced way back with MS–DOS in 1981, and it's showing its age. It was designed originally to handle files on a floppy drive, and has had minor modifications over the years so it can handle hard disks, and even file names longer than the original limitation of 8.3 characters, but it's still the lowest common denominator. The biggest advantage of FAT16 is that it is compatible across a wide variety of operating systems, including Windows 95/98/Me, OS/2, Linux, and some versions of UNIX. The biggest problem of FAT16 is that it has a fixed maximum number of clusters per partition, so as hard disks get bigger and bigger, the size of each cluster has to get larger. In a 2–GB partition, each cluster is 32 kilobytes, meaning that even the smallest file on the partition will take up 32 KB of space. FAT16 also doesn't support compression, encryption, or advanced security using access control lists.

FAT32

The FAT32 file system, originally introduced in Windows 95 Service Pack 2, is really just an extension of the original FAT16 file system that provides for a much larger number of clusters per partition. As such, it greatly improves the overall disk utilization when compared to a FAT16 file system. However, FAT32 shares all of the other limitations of FAT16, and adds an important additional limitation—many operating systems that can recognize FAT16 will not work with FAT32—most notably Windows NT, but also Linux and UNIX as well. Now this isn't a problem if you're running FAT32 on a Windows XP computer and sharing your drive out to other computers on your network—they don't need to know (and generally don't really care) what your underlying file system is.

The Advantages of NTFS

The NTFS file system, introduced with first version of Windows NT, is a completely different file system from FAT. It provides for greatly increased security, file–by–file compression, quotas, and even encryption. It is the default file system for new installations of Windows XP, and if you're doing an upgrade from a previous version of Windows, you'll be asked if you want to convert your existing file systems to NTFS. Don't worry. If you've already upgraded to Windows XP and didn't do the conversion then, it's not a problem. You can convert FAT16 or FAT32 volumes to NTFS at any point. Just remember that you can't easily go back to FAT or FAT32 (without reformatting the drive or partition), not that I think you'll want to.
The NTFS file system is generally not compatible with other operating systems installed on the same computer, nor is it available when you've booted a computer from a floppy disk. For this reason, many system administrators, myself included, used to recommend that users format at least a small partition at the beginning of their main hard disk as FAT. This partition provided a place to store emergency recovery tools or special drivers needed for reinstallation, and was a mechanism for digging yourself out of the hole you'd just dug into. But with the enhanced recovery abilities built into Windows XP (more on that in a future column), I don't think it's necessary or desirable to create that initial FAT partition.

When to Use FAT or FAT32

If you're running more than one operating system on a single computer , you will definitely need to format some of your volumes as FAT. Any programs or data that need to be accessed by more than one operating system on that computer should be stored on a FAT16 or possibly FAT32 volume. But keep in mind that you have no security for data on a FAT16 or FAT32 volume—any one with access to the computer can read, change, or even delete any file that is stored on a FAT16 or FAT32 partition. In many cases, this is even possible over a network. So do not store sensitive files on drives or partitions formatted with FAT file systems.

                 This tutorial will show you How to connect two PCs by LAN (Ethernet). There are many ways to connect two PCs, but connecting them together by LAN is the easiest and most cost effective way. Plus, you can use this method for any number of PCs.
What you need:

1. 2 PCs with Ethernet Cards or Onboard Ethernet

Most new motherboards come with onboard Ethernet, you can check this out in My Computer > Properties > Hardware > Device Manager > Network Adapter.

2. A Crossover Ethernet cable.

The normal Ethernet cables won’t work, you must have a cross crimped Ethernet cable which can be used to transmit data in both directions.

3. A Ethernet Hub

A Ethernet hub is needed if you plan to connect more than two PCs. If you want to connect just two PCs, you can do it directly without a hub.
How to do it:

1. Connect the crossover Ethernet cable to the LAN (RJ45) ports of both the PCs.

PC - 1:

- Go to My Computer > Properties > Computer Name.
- Change the Computer Name to A and Workgroup name to ABC and click OK to save changes.
- Go to Control Panel > Network Connections.
- Right click on your LAN connection and select Properties.
- Select Internet Protocol (TCP/IP) > Properties.
- Enter these values:
IP Address - 192.168.1.2
Subnet Mask - 255.255.255.0
- Leave the other fields blank and click OK to save changes.

- Go to My Computer > Properties > Computer Name.
- Change the Computer Name to B and Workgroup name to ABC and click OK to save changes.
- Go to Control Panel > Network Connections.
- Right click on your LAN connection and select Properties.
- Select Internet Protocol (TCP/IP) > Properties.
- Enter these values:
IP Address - 192.168.1.3
Subnet Mask - 255.255.255.0
- Leave the other fields blank and click OK to save changes.
- - -
After the connections and settings have been saved, both the PCs should be connected by LAN. You may need to restart both the PCs.

You can check if the connection is working by pinging one PC from the other.

For PC-1, Start > Run > CMD > ping 192.168.1.2
For PC-2, Start > Run > CMD > ping 192.168.1.3

You can view the PCs in My Network Places. You can now use this LAN connection to play multiplayer games or share files. You can also map a drive on another PC to a local drive by using My Computer > Tools > Map Network Drive > Select Drive Letter and network path of the shared folder on the other PC.

To configure Outlook 2007 for your Gmail address:

1. Enable POP in your email account. Don't forget to click Save Changes when you're done.
2. Open Outlook.
3. Click the Tools menu, and select Account Settings...
4. On the E-mail tab, click New...
5. If you are prompted to Choose E-mail Service, select Microsoft Exchange, POP3, IMAP, or HTTP, and click Next.
6. Fill in all necessary fields to include the following information:
Your Name: Enter your name as you would like it to appear in the From: field of outgoing messages. Email Address: Enter your full Gmail email address (username@gmail.com). Google Apps users, enter your full address in the format username@your_domain.com. Password: Enter your email password. Manually configure server settings or additional server types: Leave this option unchecked if you want to automatically configure Outlook 2007. If you want to manually configure Outlook 2007, check this box now. Google Apps users should configure manually as follows.
7. Click Next. If you are configuring Outlook 2007 automatically, you're done! Just click Finish.

8. If you are configuring Outlook 2007 manually, select Internet E-mail and click Next.
9. Verify your User Information, and enter the following additional information:
Server Information Account Type: POP3 Incoming mail server: pop.gmail.com (Google Apps users, enter the server names provided, don't add your domain name in these steps) Outgoing mail server (SMTP): smtp.gmail.com Logon Information User Name: Enter your Gmail username (including @gmail.com). Google Apps users, enter your full address in the format username@your_domain.com Password: Enter your email password. Require logon using Secure Password Authentication (SPA): Leave this option unchecked.
10. Click the More Settings... button, and select the Outgoing Server tab.
11. Check the box next to My outgoing server (SMTP) requires authentication and select Use same settings as my incoming mail server.

12. Click the Advanced tab, and check the box next to This server requires an encrypted connection (SSL) under Incoming Server (POP3).
13. In the Outgoing server (SMTP) box, enter 587, and select TLS from the drop-down menu next to Use the following type of encrypted connection:.

14. Click OK.
15. Click Test Account Settings... After receiving 'Congratulations! All tests completed successfully', click Close.
16. Click Next, and then click Finish.

Congratulations! You're done configuring your client to send and retrieve Gmail messages.

Figure 5.2. Data is encapsulated on the sending computer and then de-encapsulated on the receiving computer.

 

 

 

Internet Ports List

1 Port Service Multiplexer
2 Management Utility
3 Compression Process
5 Remote Job Entry
7 Echo
11 Systat Active Users
13 Daytime
17 Quote of the Day
18 Message Send Protocol
19 Character Generator
20 File Transfer (FTP) [Default Data]
21 File Transfer (FTP) [Control]
22 SSH Remote Login Protocol
23 Telnet
25 Simple Mail Transfer (SMTP)

The OSI, or Open System Interconnection, model defines a networking framework for implementing protocols in seven layers. Control is passed from one layer to the next, starting at the application layer in one station, and proceeding to the bottom layer, over the channel to the next station and back up the hierarchy.

John Wiley & Sons | ISBN: 0471375234 | 2000 | PDF | 613 pages | 4.23 MB

The bestselling guide to assembly language--now updated and expanded to include coverage of Linux. This new edition of the bestselling guide to assembly programming now covers DOS and Linux! The Second Edition begins with a highly accessible overview of the internal operations of the Intel-based PC and systematically covers all the steps involved in writing, testing, and debugging assembly programs.



http://rapidshare.com/files/290104687/Assembly_Language_Step-by-step.rar

E-Mail Servers...

Controlling e-mail servers directly can be quite interesting, and fun. This document will show some very basic ways of sending and receiving e-mail using the mail servers directly.

Sending e-mail...

Most e-mail is sent using SMTP (simple mail transfer protocol) servers. The mail programs logs into that server, sends e-mail, and logs you off. You can do that yourself! SMTP servers reside on port 25 of your e-mail server. Usually, the name is mail.yourisp.com. You telnet into that server using a telnet program. A telnet program is available to almost anybody; under UNIX and Windows. You telnet to port 25! i.e.:

telnet mail.yourisp.com 25
Once you've logged on, the server expects a greeting. The greeting is in the form of "HELO yourip." Luckily, you don't need to type in your IP (most of the time) and can just use a dot in it's place.. i.e.:

HELO .
You should note that the "dot" has spaces on BOTH SIDES! Once you've said HELO, you can start sending e-mail. First, you specify who's sending e-mail. This has to be an e-mail address with a valid server (the server's name has to exist, and DNS server has to verify it...) Usually, this would be your real e-mail; but if you're using this approach, obviously, you'd want to avoid your real e-mail. Thus, you can make up any e-mail! For example: root at NO SPAM yahoo dot com would do pretty well. It will make it seem as though the e-mail has some from there... ;-) (NOTE: do not use yahoo.com as your server!!! I like their services, and I don't want to cause them any bit of problems.) You continue by specifying:

MAIL FROM: root at NO SPAM yahoo dot com
You could also have said:

MAIL FROM:
It doesn't really matter as long as you tell the server who "you are"... Then, you have to specify the location where you want to send your e-mail... you do this:

RCPT TO: victim@somewhere.com
You could also have said:

RCPT TO:
Once you specified the location of your victim (recipient ;-), you can begin the e-mail by typing:

DATA
Note, that the first several lines you type after DATA might have special meaning. For example, after DATA, you can type:

FROM: Mr.Phreak
TO: Victim
SUBJECT: The subject of the e-mail...
You can of course, type in more screwy info... most of the rest are pretty much not standard, and will not be compatible with text only e-mail readers. Note that you don't need these lines... they're only for the receiving program to put for the user "who sent you the e-mail" mgs... avoiding them will simply leave the e-mail with no subject, the "TO" field will have "undisclosed recipient;" and the "FROM" field will have your e-mail you've specified in the "MAIL FROM" field. After these three lines, you can being your e-mail text. The text can be anything, and multi-lined. You end the e-mail by typing a dot at the beginning of a line. For example, you end the e-mail this way:

see you later ;-)
.
See that little dot at the last line? To quit from the server, you simply type QUIT... i.e.:

QUIT
After QUIT, the server disconnects you. Notice that the only revealing thing in the e-mail will be your IP address. Which if you use a publicly available workstation (the library), and/or telnet into several other servers before hand, will pretty much be hard to trace...

Receiving E-Mail...

Receiving e-mail using a mail server directly isn't much fun. (and most of the times, I'd definitely not recommend it.) Anyway, there are times where this comes in useful. (for example, deleting junk mail without downloading it...)

Most people read e-mail using a POP3 mail server. A POP3 server resides on port 110, usually referred to as "pop3"... you telnet into that server by:

telnet mail.yourisp.com pop3
You could also have said:

telnet mail.yourisp.com 110
As soon as you logon, the server is in it's AUTHENTICATION mode... and expects you to type in your username and password. You do this by:

USER username
PASS password
If you make an error, you can try again... (it will let you know that the password/username is not valid...) Once you logon, you'll be in the TRANSFER mode... (or something) At that point, you can see how many msgs you got, and read them. For example, you can type:

STAT
To give you statistics about your e-mail... (basically, the size of e-mails...) Similar goes for the LIST command... i.e.:

LIST [msg]
The [msg] there is optional, if you want to find out stuff about an individual e-mail, you use it. (I almost always use LIST with no parameters). After you know how many e-mails you got, you can read (well...almost) each individual e-mail by typing:

RETR msg
Where "msg" is the e-mail number gotten from LIST command. The only disadvantage is that if the e-mail is large, it just zoomes past you, and you can hardly read it... (that's why I suggest an e-mail program)

To delete an e-mail you type:

DELE msg
This deletes (marks as deleted) the msg number pointer to by "msg". I say "marks as deleted" because it doesn't actually get deleted at that point. It will only be deleted when you leave the server. You can actually undelete the e-mails by typing:

RSET
That's it for the standard (required) POP3 commands, but MOST servers implement the optional ones as well... (which I won't describe here) However, I'll mention the most useful one (at least to me), the TOP msg n.

TOP msg n
Where the msg is the msg to display, and n is the number of lines to display... thus, you can see the header of an e-mail, without reading (or downloading) the whole e-mail.

You leave the server by typing QUIT...i.e.:

QUIT
At this point, the server deletes all the msgs marked as deleted (cleans up stuff), and waits for the next logon...

A suggestion is not to take up the POP3 server for a long time... since when you've logon, it locks everything. (and somebody who's sending you e-mail might not be able to get through on some configurations)

That's it for handling the e-mail servers directly. Most of these though, are more conveniently used in a small networking program... (writing your own mail client...) In which case, you'd want to take a look at [RFC1939] document for POP3, and [RFC822] document for SMTP.

NOTE: A very important note, most of these servers don't echo back the characters, thus, if you're typing, you won't see your text appear in the telnet window. (To fix it under Windows, you setup your terminal window to echo the characters locally.) Under UNIX, you can just telnet into another machine, that way, that other machine will echo the characters to you (not the mail server).

Good luck! (and don't use this info to send hard to trace junk mail)

Note: Most of the ISP would hve blocked port 25 by default. try for ur luck

1. open cmd
2. type "ping www.google.com"
3. and ip address will appear next to name
4. go to ip-address.com
5. and at the bottom there is ip tracking.......... press
6. in the box type the ip and there you have it
7. you can change the website

Newspapers Internet magazines came with cover stories when Denial of service (DoS) attacks assaulted a number of large and very successful companies' websites last year. Those who claim to provide security tools were under attack. If Yahoo, Amazon, CNN and Microsoft feel victim to DoS attacks, can any site-owner feel safe?

In this article we'll try to make site owners understand the "In and Outs" of DoS andDDoS attack methods, vulnerabilities, and potential solutions to these problems. Webmasters are usually seen searching for solutions to new security threats and ways of patching-up before it is too late.
DoS:
In a Denial of Service (DoS) attack, the attacker sends a stream of requests to a service on the server machine in the hope of exhausting all resources like "memory" or consuming all processor capacity.

DoS Attacks Involve:
Jamming Networks
Flooding Service Ports
Misconfiguring Routers
Flooding Mail Servers
DDoS:
In Distributed DoS (DDoS) attack, a hacker installs an agent or daemon on numerous hosts. The hacker sends a command to the master, which resides in any of the many hosts. The master communicates with the agents residing in other servers to commence the attack. DDoS are harder to combat because blocking a single IP address or network will not stop them. The traffic can derive from hundred or even thousands of individual systems and sometimes the users are not even aware that their computers are part of the attack.

DDoS Attacks Involve:
FTP Bounce Attacks
Port Scanning Attack
Ping Flooding Attack
Smurf Attack
SYN Flooding Attack
IP Fragmentation/Overlapping Fragment Attack
IP Sequence Prediction Attack
DNS Cache Poisoning
SNMP Attack
Send Mail Attack

Some of the more popular attack methods are described below.

FTP Bounce Attack

FTP (File Transfer Protocol) is used to transfer documents and data anonymously from local machine to the server and vice versa. All administrators of FTP servers should understand how this attack works. The FTP bounce attack is used to slip past application-based firewalls.

In a bounce attack, the hacker uploads a file to the FTP server and then requests this file be sent to an internal server. The file can contain malicious software or a simple script that occupies the internal server and uses up all the memory and CPU resources.

To avoid these attacks, the FTP daemon on the Web servers should be updated regularly. The site FTP should me monitored regularly to check whether any unknown file is transferred to the Web server. Firewalls also help by filtering content and commands. Some firewalls block certain file extensions, a technique that can help block the upload of malicious software.

Port Scanning Attack

A port scan is when someone is using software tosystematically scan the entry points on other person’s machine. There arelegitimate uses for this software in managing a network.

Mosthackers enter another’s computer to leave unidentifiable harassing messages,capture passwords or change the set-up configuration. The defense for this isthrough, consistent network monitoring. There are free tools that monitor forport scans and related activity.

Ping Flooding Attack

Pinging involves one computer sending a signal to anothercomputer expecting a response back. Responsible use of pinging providesinformation on the availability of a particular service. Ping Flooding is theextreme of sending thousands or millions of pings per second. Ping Flooding cancripple a system or even shut down an entire site.

APing Flooding Attack floods the victim’s network or machine with IP Pingpackets. At least 18 operating systems are vulnerable to this attack, but themajority can be patched. There are also numerous routers and printers that arevulnerable. Patches cannot currently be applied throughout a global networkeasily.

Smurf Attack

A Smurf Attack is modification of the "ping attack"and instead of sending pings directly to the attacked system, they are sent to abroadcast address with the victim’s return address. A range of IP addressesfrom the intermediate system will send pings to the victim, bombarding thevictim machine or system with hundreds or thousands of pings.

One solution is to prevent the Web server from being usedas a broadcast. Routers must be configured to deny IP-Directed broadcasts fromother networks into the network. Another helpful measure is to configure therouter to block IP spoofing from the network to be saved. Routers configured assuch will block any packets that donor originate in the Network.To be effective this must be done to all routers on the network.

SYN Flooding Attack

This attack exploits vulnerability in the TCP/IPcommunications protocol. This attack keeps the victim machine responding back toa non-existent system. The victim is sent packets and asked to response to asystem or machine with an incorrect IP address. As it responds, it is floodedwith the requests. The requests wait for a response until the packets begin totime out and are dropped. During the waiting period, the victim system isconsumed by the request and cannot respond to legitimate requests.

When a normal TCP connection starts, a destination hostreceives a SYN (synchronize/start) packet from a source host and sends back aSYN ACK (synchronize acknowledge) response. The destination host must the hearan acknowledgement, or ACK packet, of the SYN ACK before the connection isestablished. This is referred as the "TCP three-way handshake”.

Decreasingthe time-out waiting period for the three way handshake can help to reduce therisk of SYN flooding attacks, as will increasing the size of the connectionqueue (the SYN ACK queue). Applying service packs to upgrade older operatingsystems is also a good countermeasure. More recent operating systems areresistant to these attacks.

IPFragmentation/Overlapping Fragment Attack

To facilitate IP transmission over comparatively congestednetworks. IP packets can be reduced in size or broken into smaller packets. Bymaking the packets very small, routers and intrusion detection systems cannotidentify the packets contents and will let them pass through without anyexamination. When a packet is reassembled at the other end, it overflows thebuffer. The machine will hang, reboot or may exhibit no effect at all.

Inan Overlapping Fragment Attack, the reassembled packet starts in the middle ofanother packet. As the operating system receives these invalid packets, itallocates memory to hold them. This eventually uses all the memory resources andcauses the machine to reboot or hang.

IPSequence Prediction Attack

Usingthe SYN Flood method, a hacker can establish connection with a victim machineand obtain the IP packet sequence number in an IP Sequence Prediction Attack.With this number, the hacker can control the victim machine and fool it intobelieving it’s communicating with another network machines. The victim machinewill provide requested services. Most operating systems now randomize theirsequence numbers to reduce the possibility of prediction.

DNSCache Poisoning

DNS provides distributed host information used for mappingdomain names and IP addresses. To improve productivity, the DNS server cachesthe most recent data for quick retrieval. This cache can be attacked and theinformation spoofed to redirect a network connection or block access to the Web sites),a devious tactic called DNS cache poisoning.

The best defense against problems such as DNS cachepoisoning is to run the latest version of the DNS software for the operatingsystem in use. New versions track pending and serialize them to help preventspoofing.

SNMP Attack

Most network devices support SNMP because it is active bydefault. An SNMP Attack can result in the network being mapped, and traffic canbe monitored and redirected.

The best defense against this attack is upgrading toSNMP3, which encrypts passwords and messages. SinceSNMP resides on almost all network devices, routers, hubs, switches, Servers andprinters, the task of upgrading is huge. Some vendors now offer an SNMP Managementtool that includes upgrade distribution for global networks.

UDP Flood Attack

AUDP Flood Attacks links two unsuspecting systems. By Spoofing, the UDP floodhooks up one system’s UDP service (which for testing purposes generates aseries of characters for each packet it receives) with another system’s UDPecho service (which echoes any character it receives in an attempt to testnetwork programs). As a result a non-stop flood of useless data passes betweentwo systems.

Send Mail Attack

In this attack, hundreds of thousands ofmessages are sent in a short period of time; a normal load might only be 100 or1000 messages per hour. Attacks against Send Mail might not make the front page,but downtime on major websites will.

For companies whose reputation dependson the reliability and accuracy of their Web-Based transactions, a DoS attackcan be a major embarrassment and a serious threat to business.

Conclusion

Frequent denial-of-service attacks and achange in strategy by "Black-Hat Hackers" are prompting enterprises todemand technology that proactively blocks malicious traffic.

Tools and services that reflectapproaches to combat such DoS attacks have been introduced with time. These arenormally upgrades to what was produced before. No solution is ever said to be anultimate solution to defend DoS attacks. Despite the new technology coming everyday, the attacks are likely to continue.