Just how secure is your network? It’s a question many IT managers ask
themselves daily. Chances are, your network’s perimeter is locked up
tight with a strong corporate firewall. Unfortunately, those who pose the
greatest risk may already have a key. Employees, telecommuters, strategic
vendors, temporary employees, and business partners require access to most
networks today - the same networks that include sensitive customer data
and financial records.
Given the critical need to keep everyone productive and still protect
your company’s intellectual property, it’s no wonder so many IT
managers are feeling a little insecure about network access.
Some Hard Facts
A joint survey conducted by the CSI and FBI found that in 2002, 90
percent of respondents had detected network security breaches over the
last 12 months. Approximately 80 percent reported financial losses due to
these breaches. Among companies who quantified these losses, the average
cost was more than $2 million. In short, the threat of unauthorized
network access is very real and the effects can be catastrophic.
The Internet has changed the way people work, communicate, collaborate,
buy and sell. Business trends, such as outsourcing and telecommuting,
further complicate a corporation’s security challenges. Controlled
access between corporate networks is often the most practical,
cost-effective way to enable business partnerships. But allowing partners
deep into the corporate network blurs the distinction between inside and
outside access.
The traditional security paradigm of “assuming connections inside the
perimeter firewall are safe and connections outside the firewall are
suspect,” is not nearly enough to protect a company’s digital assets.
Today’s enterprise networks need security that extends from the server
to all its end points, whether they’re inside or outside the corporate
perimeter.
Beyond Perimeter Firewalls
Conventional perimeter firewalls only protect the perimeter of the
corporate network. They filter and audit traffic as it crosses the
boundary between the LAN inside the company and the Internet outside.
However, they’re not designed to safeguard individual connections within
the LAN. This would be analogous to putting a lock on the main entrance to
an office building but leaving individual rooms or offices unlocked - once
a person got past the main door, they could get to anything inside the
building. This type of network is particularly vulnerable to a targeted
attack. For example, a hacker targets machines that have inside access to
the corporate LAN. Once they’ve gained control of such a machine, they
use it as a launching pad to break into other systems.
The obvious way to improve security in a building would be to create
keys and locks for each room inside it. Similarly, the latest generation
of security solutions distributes firewall functions to desktop, notebook
and server PCs across the network. Embedding firewalls throughout the
company gives users easy access to information - without opening the rest
of the network to a potential invasion. With this type of end-to-end
security, it wouldn’t matter whether users connect through intranets,
extranets, VPNs or remote access. It also helps prevent an intrusion at a
single end point from progressing further into the network or a public
login from being used to break into a restricted-access machine.
Safe, Safer, Safest
Although all companies should be concerned about security, some must be
particularly attentive. Organizations that store and rely on confidential
and/or proprietary information require a particularly robust and reliable
solution. These organizations include government agencies, financial
institutions, insurance services, high-tech developers and health care
providers.
Many organizations are becoming more and more distributed, with
networks that include branch offices, partners, telecommuters and remote
workers. As networks become increasingly distributed, network security
must adjust to meet the changing nature of the network. Embedding hardware
security at each of these new end points - putting locks on each door
within the building - quickly becomes a viable option to ensure a
consistent, sound security policy across the distributed network.
Software-based solutions - such as personal firewalls and anti-virus
scanners - are simply not tamper-resistant enough. These solutions are
only as secure as the operating systems of the servers or PCs where they
reside. Once the operating system is compromised, the software security
solution is effectively rendered useless. End-user action or even a
malicious script delivered via email can easily disable software security
products. It’s even possible for “friendly” applications running on
the host computer to inadvertently turn off security software to eliminate
a driver conflict. Once these software solutions fail, the end system is
left vulnerable. Worse yet, the rest of the network is at risk of
penetration from this potential launching pad.
Perimeter firewall appliances or gateways offer superior
tamper-resistance because their security functions are handled by hardware
processors, not software. But as noted, these devices are limited to
boundary protection. A NIC-based firewall solution extends this
functionality beyond the perimeter and distributes it to network end
points. It provides both bypass-and tamper-resistance. Security
enforcement happens at the PC but is handled by the firewall hardware,
separate from the host system - which makes it virtually invulnerable to
malicious code or hacker attacks. Even in the unlikely event that an
attacker can execute code on a firewall-enabled host, they will be
severely restricted. They can’t turn off or go around the embedded
hardware firewall and progress further into the network.
As distributed networks expand, the ability to centrally monitor and
manage the security infrastructure becomes critical. Just as it would be
preferable for a security guard to lock and unlock any door from his
security base station, rather than walk from room to room with a giant
keychain, so it provides significant benefits for companies to configure
and manage network security from a central control console. It enables IT
administrators to easily regulate network security to fit changing
business needs and maintain better control over user access. Security
policies can be created and enforced for a specific machine (i.e. payroll
server) or for a group of machines (i.e. all web servers). For example, IT
staff can quickly adjust security levels in response to a newly detected
network attack, as reported by the intrusion detection system (IDS), and,
if necessary, shut down inbound and/or outbound traffic to any given
machine or group of machines equipped with the embedded hardware firewall
One of the greatest challenges IT managers face with a distributed
network is enforcement of security policy. Security that is controlled
from a remote server is very difficult to turn off at the end points,
especially if it is hardware embedded on an individual machine. IT
administrators can be confident that once they deploy the appropriate
security across the network, users and systems are safeguarded - and will
stay that way.
The Emerging Home Work Force
A hardware-based firewall security solution at the PC level also
protects telecommuting users who access the corporate LAN from home. PCs
in the home are particularly vulnerable to hackers because most
residential Internet services operate over open connections, with no added
security. They are at an even greater risk if they are using a DSL router
or cable modem. These “always-on” broadband connections are more
vulnerable to hackers than dial-up modems because they keep computers
connected to the Internet 24 hours a day. Dial-up services typically
assign a user a new IP address on the Internet each time they connect, but
broadband providers often assign a permanent Internet address to each
customer, making it easier for an attacker to “lock on” to their
connection.
Unfortunately, the number of attacks occurring on home PCs is rising as
hackers discover these easy targets. That’s the recent assessment of
Carnegie Mellon’s CERT Coordination Center, which tracks computer
security threats and disseminates information on how to protect against
attacks. According to CERT, the number of hacker attacks on home computers
rose sharply in 2001. In many cases, hackers aren’t going after personal
files, but are simply using the computers to gain access to corporate
networks. Securing these remote access endpoints with NIC-based firewalls
helps protect the rest of the corporate network from risky Internet
connections.
Time for Secure, End-to-End Connections
With global hacking events and virus incidents on the rise, it’s no
wonder many companies consider network security an essential factor in
ensuring business profitability. Microsoft, eBay, Yahoo! and Amazon.com
are a few corporate giants whose operations came to a grinding halt
because of network breaches. Email viruses, such as Code Red, Sircam and
Nimda, have increasingly become mainstream business news.
As hackers and virus writers continue to get craftier, network security
products must evolve to stay ahead of them. PC-based, hardware firewalls
add an essential layer of tamper-resistant, distributed protection to any
smart security solution. Firewall hardware can be easily integrated into
notebooks, desktops, and servers at the factory to deliver secured systems
right off the shelf. Security-conscious corporate customers should ask
their PC manufacturers if they offer firewall-enabled systems to secure
the last unprotected are of the network: the personal computer.
James Teel is senior director of security solutions business management
at 3Com Corporation (www.3com.com).