One Way Only
Unidirectional connectivity protects airport networks using IP cameras
- By Lior Frenkel
- Sep 01, 2008
Airports are bustling international hubs, some
providing services to hundreds of thousands
of people from diverse locations on a daily
basis. Overseeing airport security is an extremely
complicated task, not just in the airport itself, but also
on the airplanes.
Following the Sept. 11, 2001, terrorist attacks, a
greater focus on airport security arose specifically
designed to prevent terrorist activity. Naturally, technology
has been harnessed to aid in this challenge. One
example is the growing deployment of advanced IPbased
video surveillance systems. However, one must
not forget other grave security concerns in airports—
ranging from air traffic control systems to securing an
airport’s energy systems such as generators, air conditioning,
customs and border control computers, and Xray
machines.
Today, such energy centers are computer-controlled
and monitored and, therefore, must be protected against
cyber attacks. Technological innovations can greatly
assist in providing improved security. IP-based surveillance
systems have many benefits over older-generation
analog and digital systems. For example, IP cameras
enable on-camera automated alerting, generated in
response to predefined events. Furthermore, IP-based
surveillance systems allow the possibility of advanced
and automatic analytics of numerous video feeds to
identify predefined events, threats and fraud.
IP Advantages and Risks
Although some analytic capabilities are available as addons
to analog systems, the full technological advantages
are only available in IP networks, where seamless integration
with additional systems provides added functionality
as well as greater simplicity and efficiency.
However, when handled with insufficient attention
and prudence, technology can become a double-edged
sword. Despite their undisputed advantages, IP-based
surveillance systems also entail grave risks that are not
relevant in analog systems. When employing IP surveillance,
an attacker can access a surveillance network simply
by disconnecting the LAN cable of a camera—often
located outside of the physical security perimeter or in
an unattended location—and connecting it to a laptop.
This allows access to other devices on the same network,
for instance any additional cameras, surveillance
servers, monitors and storage.
If the network is connected to additional airport networks,
the hacker can access these networks as well. Thus,
a hacker is able to cause a wide range of damage to airport
security, including blocking a camera or a set of cameras,
shutting down the entire surveillance system and
changing or deleting stored video footage. If the surveillance
network is connected to additional networks, the
hacker also can interrupt IT systems across the airport.
If the access and entry control system is reached, a
hacker can manipulate and operate security access controls
within the airport, permitting entry to closed highsecurity
zones. Where wireless technology (Wi-Fi or Wi-
Max) is used to connect cameras in areas with no cable
infrastructure, the hacker’s task is even easier as no physical
tapping is necessary. The fact is, IP cameras function
as guards but are often not sufficiently guarded
themselves. The critical question then becomes who
guards the guard?
The double-edged sword facet of advanced technology
is well reflected in air traffic control technology as well.
Naturally, the more sophisticated the means at the disposal
of air traffic control personnel, the better they are equipped to coordinate aerial activity and
secure airplane takeoffs and landings
within their airspace. However, sophistication
normally means connectivity to additional
information and data sources, which
in turn means greater threat exposure.
Receiving remotely generated air-traffic
control video feeds is a good example
of a technological advancement that has
improved the air-traffic security generated
with more informed and aware personnel
but also has increased networks’ vulnerability
by complex interconnections
and distributed security responsibilities.
There is no shortage of news about similar
critical systems being cyber attacked
or found vulnerable to such attacks when
pre-emptively inspected.
Likewise, systems such as an airport’s
energy center most often are remotely
monitored to ensure functionality of mission-
critical services. Remote monitoring,
however, also entails connectivity to external
sources and networks, thus exposing
the monitored network to attack.
Unfortunately, it has been proven time
and again that even with the use of security
products such as firewalls, intrusion
detection and prevention systems, there is
never a guarantee of full protection
against attacks because all software and
logic-based solutions are vulnerable and
prone to remote manipulation.
Considering that airports and airplanes
are some of the most lucrative terrorist
targets, the premise must be that a lot of
effort would be invested in order to overcome
potential threats. Therefore, none of
the above-mentioned solutions provide
the adequate level of security required to
protect airport mission-critical networks.
Unidirectional Protection
When dealing with airport security, one
must deploy a powerful and absolute
security solution that is not vulnerable to
standard attack technologies and is
immune to software flaws, bugs and, of
course, human errors. To fully protect
such networks, a foolproof and futureproof
solution is required. Unidirectional
connectivity is the only security solution
that can provide full protection to such
remote monitoring networks.
A unidirectional connection, also
referred to as a one-way link, is a communication
appliance that allows data to
pass through in one direction only. Thus,
video streams and camera metadata can be transferred only from a camera to the
airport’s surveillance network, and not
vice versa. Similarly, there would be no
bidirectional connection with air traffic
control networks, and thereby threats of
cyber attacks would be completely eliminated.
As for an airport’s energy centers,
data necessary for monitoring will be
passed from the energy center to the
monitoring network or to third-party
maintenance and control centers, but not
vice versa. Therefore, once more, no
online attack against the energy center
would be possible.
The point in each of these scenarios is
that where data must logically flow in one
direction only, a unidirectional link can
be implemented, enforcing strict security
without impairing functionality.
Innovative Security
A secure unidirectional communication
system must enforce its unidirectional
data flow by means of physical hardware
as opposed to software and other
logical ways. The system is comprised
of two hardware components that are
physically capable of communicating
with each other, one way only. One
component can only transmit to the
other, and not vice versa. This is accomplished
by connecting the two components
via fiber-optic cable with the
transmitting component having only a
transmitter—a laser LED—and the
receiving unit having only a receiver—a
photoelectric cell. In such a way, data
can physically flow only from the transmitter
to the receiver.
To facilitate reliable data transfer over
a unidirectional medium, a unique communication
protocol must be implemented.
This protocol adds communication
reliability, as well as another layer of
security to the system, by allowing transfer
of the payload. For example, raw
video data in IP video surveillance only
means stripping it from headers and other
protocol fields commonly used to facilitate
malicious attacks.
Based on patent-pending technology,
this unidirectional connectivity concept
can be implemented for securely transmitting
any type of remote monitoring
data, be it video streams, air traffic control
data or any other type of data pertaining
to remote monitoring scenarios. In
every scenario, the unidirectional link
will enable data to flow securely from the
sensor to the monitoring network or monitoring
and control center.
As the data will be flowing only one
way, there will be no threat of online
hacking attacks. There simply will be no
return link at the hacker’s disposal.
Airport security officials should use the
added advantages technology offers them
when battling terrorism, crime or accidents.
The solution lies with the only available
foolproof and future-proof security
technology—unidirectional
connectivity.