Network Security Risks
The open architecture of the Internet Protocol (IP) makes it a
highly efficient, cost-effective, and flexible communications
protocol for local and global communications. It has been
widely adopted, not only on the global Internet, but also in
the internal networks of large corporations.
The IP protocol suite, including TCP/IP, was designed to
provide reliable and scalable communications over real-world
networks. It has served this goal well. However, it was
designed twenty years ago in a world where the Internet
consisted of a few hundred closely controlled hosts. The
situation has changed. The Internet now connects dozens of
millions of computers, controlled by millions of individuals
and organizations. The core network itself is administered by
thousands of competing operators, and the network spans the
whole globe, connected by fibers, leased lines, dial-up modems,
and mobile phones.
The phenomenal growth of the Internet has peaked the interest
of businesses, military organizations, governments, and
criminals. Suddenly, the network is changing the way business
is done. It is changing the nature of trade and distribution
networks and the way individual people communicate with each
other.
The upsurge of business, scientific, and political
communications on the Internet has also brought out the usual
negative elements. Criminals are looking for ways of getting a
cut of the emerging business. Industrial espionage has moved
online. Intelligence agencies are showing a growing interest
towards networked communications, and they often exchange
information with domestic commercial interest and political
groups. Crackers, exchanging information and source code, make
attacks that ten years ago were thought to be within the reach
of only the most powerful intelligence agencies.
It has turned out that the IP protocol, while very tolerant of
random errors, is vulnerable to a number of malicious attacks.
The most common types of attacks include:
- Eavesdropping a transmission, for example looking for
passwords, credit card numbers, or business secrets.
- Hijacking, or taking over a communication in such a way
that the attacker can inspect and modify any data being
transmitted between the communicating parties.
- IP spoofing, or faking network addresses in order to
fool access control mechanisms based on them or to redirect
connections to a fake server.
The SSH2 protocol is designed to protect network communications
against security hazards like these.
