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Cryptography

Identification and authentication techniques sometimes use biometric information to add further confidence that users are legitimate when attempting physical or logical access to system resources. Single sign-on and associated technologies and protocols aim to reduce the proliferation of IDs and passwords to better control the security of access control mechanisms both within and outside the organization. Industry alliances, such as the Liberty Alliance, are moving toward federated identities that permit single sign-on or reduced sign-on for e-commerce users.

Cryptography relies on two basic methods: transposition and substitution. With transposition, ciphertext is created by scrambling a message based on a shared secret key. In substitution, letters are exchanged with other letters based on a substitution pattern known by both the sender and receiver. The strength of a cryptosystem rests in the size and means used to protect cryptographic keys; in general, the longer the key, the harder it is to break the encryption. The same key can be used to both encrypt and decrypt information and is called a symmetric key, or different keys can be used for encryption and decryption and are called asymmetric keys.

Digital signatures are used in asymmetric key cryptography to protect a message’s content from disclosure, prove the integrity of a message upon receipt, and verify that the sender of the message is indeed who he or she claims to be. Digital signature technology relies on a Public Key Infrastructure for implementation and is at the heart of many commercial products that are used in modern electronic commerce.

Virtual private networks (VPN)

Virtual private networks (VPN) are secure connections over the Internet that enable remote users and sites to connect to a central network. You can use PPTP, L2TP, or IPSec to create a VPN. IPSec is considered the most secure of the three. Administrators creating a VPN protocol should consider how the packets are encrypted, what sort of authentication is used, and whether the current hardware and software supports that technology. The protocols used by many common attacks are ICMP, UDP, and TCP. IP address spoofing is a serious threat, and although there are various techniques for avoidance, including reverse path forwarding, route filtering, and reverse DNS look-up exist, none are foolproof by themselves. Used in combination with other firewall methods, such as ignoring ICMP echo requests sent to broadcast addresses, it may reduce the impact of DoS attacks in which IP address spoofing is prevalent.

Each category of firewall has its own unique set of features and functionality, and you must perform a careful analysis to determine which firewall is needed in your environment. Personal firewalls are needed even in an environment where an enterprise firewall is installed, since they protect a computer from internal attacks. One economical personal firewall is available on any Windows XP system. It provides incoming protection and should be used if no other firewall will be installed on the host computer. Other personal firewalls, such as Zone Alarm, provide enhanced functionality that goes beyond the capabilities of the Windows Firewall.

Computer Programmer Jobs

The median annual wage for computer programmers was $108,530 in May 2021. Employment of software developers is projected to grow 15 percent from 2021 to 2025, much faster than average. Software developers also need skills related to the industry in which they work. Developers working in a bank, for example, should have knowledge of finance so that they can understand a bank's computing needs. In fact, many students gain experience in software development by completing an internship at a software company while in college.