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Login Security in .NET Printing ANSI/AIM Code 128 in .NET Login Security

Login Security using barcode integration for visual studio .net control to generate, create barcode 128 image in visual studio .net applications. console app Without a secure host, good .NET code 128 code set c login security cannot add much protection. Table C-1 lists some of the best login security tools, including replacement daemons for telnetd, rlogind, and rshd.

The current choice of most sites is ssh, which comes as both freeware and a commercially supported package that works on UNIX/Linux, Windows, and Macintosh platforms. The PAM facility (page 458) allows you to set up multiple authentication methods for users in series or in parallel. In-series PAM requires multiple methods of authentication for a user.

In-parallel PAM uses any one of a number of methods for authentication. Although it is not the most popular choice, you can configure your system to take advantage of one-time passwords. S/Key is the original implementation of one-time passwords by Bellcore.

OPIE (one-time passwords in everything), which was developed by the U.S. Naval Research Labs, is an improvement over the original Bellcore system.

In one permutation of one-time passwords, the user gets a piece of paper listing a set of one-time passwords. Each time a user logs in, she enters a password from the piece of paper. Once used, a password becomes obsolete, and the next password in the list is the only one that will work.

Even if a malicious user compromises the network and sees your password, the information will be of no use. 7. CERT is slow but useful as a medium for coordination between sites. It acts as a tracking agency to document the spread of security problems.

. Host Security 1055 because the pas sword can be used only once. This setup makes it very difficult for someone to log in as you but does nothing to protect the data you type at the keyboard. One-time passwords are a good solution if you are at a site where no encrypted login is available.

A truly secure (or paranoid) site will combine one-time passwords and encrypted logins. Another type of secure login that is becoming more common is facilitated by a token or a smartcard. Smartcards are credit-card-like devices that use a challenge response method of authentication.

Smartcard and token authentication rely on something you have (the card) and something you know (a pass phrase, user ID, or PIN). For example, you might enter your username in response to the login prompt and get a password prompt. You would then enter your PIN and the number displayed on the access token.

The token has a unique serial number that is stored in a database on the authentication server. The token and the authentication server use this serial number as a means of computing a challenge every 30 to 60 seconds. If the PIN and token number you enter match what they should be as computed by the access server, you are granted access to the system.

. Remote Access Security Issues and solu tions surrounding remote access security overlap with those pertaining to login and host security. Local logins may be secure with simply a username and password, whereas remote logins (and all remote access) should be made more secure. Many breakins can be traced back to reusable passwords.

It is a good idea to use an encrypted authentication client, such as ssh or kerberos. You can also use smartcards for remote access authentication. Modem pools can also be an entry point into a system.

Most people are aware of how easy it is to monitor a network line. However, they may take for granted the security of the public switched telephone network (PSTN, also known as POTS plain old telephone service). You may want to set up an encrypted channel after dialing in to a modem pool.

One way to do so is by running ssh over PPP. There are ways to implement stringent modem authentication policies so that unauthorized users are not able to use your modems. The most common techniques are PAP (Password Authentication Protocol), CHAP (Challenge Handshake Authentication Protocol), and Radius.

PAP and CHAP are relatively weak when compared with Radius, so the latter has rapidly gained in popularity. Cisco also provides a method of authentication called TACACS/TACACS+ (Terminal Access Controller Access Control System). One or more of these authentication techniques are available in a RAS (remote access server in a network a computer that provides network access to remote users via modem).

Before purchasing a RAS, check what kind of security it provides and decide whether that level of security meets your needs. Two other techniques for remote access security can be built into a modem (or RAS if it has integrated modems). One is callback: After you dial in, you get a password.

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