IT Risk Assessment for CyberTrans Ltd.: WLAN and VoIP

Overview of CyberTrans Ltd.

This paper presents a risk assessment for CyberTrans Ltd., a logistics firm facing relocation and system upgrade challenges. The company plans to relocate its technology base to a new site within two years and upgrade its systems to Wireless LAN and VoIP in order to support a cost-effective relocation. The latest technologies, including fiber optics, are to be incorporated, and the firm's satellite tracking solution may be outsourced, though ownership and control will remain with CyberTrans Ltd. A risk assessment is carried out and recommendations are provided.

CyberTrans Ltd. is a logistics firm that provides next-day delivery services throughout the UK for packages weighing up to 50 kg, as well as a three-day service for shipments over 50 kg. The company operates a national fleet of vehicles ranging from small vans to 38-tonne articulated trucks. All vehicles are fitted with satellite tracking devices that allow the firm to know the exact location of each vehicle at any point in time. The tracking system is hosted on a leased server based off-site, with 24-hour maintenance.

Overview of Applicable Technologies

Wireless LAN Technology

A Wireless Local Area Network (WLAN) is a form of LAN that uses radio frequency (RF) to communicate rather than wires. Wireless clients connect to the WLAN via wireless access points (WAPs).

Teare and Paquet (2005) identify three main advantages of WLAN:

• It provides flexibility.
• It increases overall productivity.
• It results in cost savings compared to wired networks.

All of these advantages are highly relevant to CyberTrans, given its need to relocate as quickly and cost-effectively as possible. Flexibility is particularly important, as it allows the free movement of staff and equipment within the office.

Flexible Work Environment

The WLAN would allow CyberTrans Ltd. staff to easily access printers, servers, and other network resources regardless of their physical location, subject to wireless network coverage. A laptop connected to the CyberTrans access point can remain connected anywhere within the company's wireless network coverage area. Employees can work from their cubicles, the cafeteria, or meeting rooms. This flexibility would also allow CyberTrans Ltd. to move machines and personnel around the office without the need to run extension network cables.

Increased Productivity

A study by NOP World Technology for Cisco Systems in November 2003 found that WLAN users remained connected to the corporate network approximately 3.64 hours longer per day than their wired counterparts, increasing productivity by twenty-seven percent (Cisco, 2003). This productivity gain is directly relevant to CyberTrans operations.

Low Deployment Cost

Another key benefit of WLAN deployment is its low cost. The total cost of ownership (TCO) is considerably lower than the benefits it delivers to the organization (Teare and Paquet, 2005). This advantage is subject to the caveat that the WLAN must be well managed and secured.

The Wireless Components

The CyberTrans corporate WLAN is to consist of wireless access points and wireless client devices.

Wireless Access Points: These provide connectivity to CyberTrans wireless client devices such as laptops, desktops, printers, and IP phones. Given the complex nature of CyberTrans's services, an integrated wireless access point is recommended. Cisco integrated access point systems are suitable — specifically, a high-speed wireless interface card (HWIC) installed using Cisco 2800 or 3800 series routers. These routers can concurrently route, switch, and provide security services on a single platform with IEEE 802.11 Wireless LAN functionality (Cisco, n.d.). The Cisco HWIC-AP WLAN Module for Cisco 1800, 2800, and 3800 series is appropriate for the convergence of IP communication with IP telephony.

Wireless Client Devices: Wireless client devices are equipped with wireless interface cards (WICs) for communication over WAPs and RF. They include laptops, workstations, PDAs, and wireless IP phones. CyberTrans's modernization plan includes implementing wireless IP telephony in its call centers. Phones implemented on 802.11b technology should include built-in security features such as Quality of Service (QoS) and management capabilities. CyberTrans should deploy the Cisco Unified Wireless IP Phone 7920 for this purpose (Cisco, 2005).

Secure Hosting Server

A secure hosting server is essential for CyberTrans to effectively host its vehicle tracking system using its own resources. The server must be secure and reliable, and must uphold the three tenets of information security: confidentiality, availability, and integrity. The recommended hosting server is the HP ProLiant G6 Server equipped with Intel Xeon 5500 processors, running Red Hat Enterprise Linux 5.2. The vehicle tracking software to be used is WebTMC — a web server dedicated to telemetry, monitoring, control, and vehicle tracking (Methos Consulting, 2011).

Fiber Optic Technology

A fiber optic framework is to be used to provide a Wide Area Network (WAN) connection between the main office and the new off-site location housing the tracking servers, customer liaison operations, and finance operations. This is to be implemented using a broadband service from Virgin Media's fiber optic network, with a 100 Mb option to enable fast and secure exchange of information between offices and headquarters.

Wireless LAN Risk Assessment

Risk assessment is defined by PC Magazine (n.d.) as a report that identifies an organization's vulnerabilities and estimates the recovery cost in the event of damage. It also summarizes defensive measures and their associated costs relative to the level of risk the organization is willing to accept — the organization's risk tolerance. Risk analysis is the process of conducting the risk assessment. Within risk analysis, threats refer to harmful events and acts such as the deployment of malware and unauthorized network access. Risk is the probability that a given threat will succeed and the extent of potential damage.

Wireless network technologies offer several advantages over wired networks, including:

1. Support for mobility
2. Rapid deployment of network resources
3. Flexibility in implementation
4. Scalability

Frequency Allocation for the Wireless Spectrum

The industrial, scientific, and medical (ISM) frequency band allocations relevant to WLAN are as follows (Bruce, 2002):

• 902 MHz – 928 MHz (26 MHz total bandwidth)
• 2.4 GHz – 2.4835 GHz (83.5 MHz total bandwidth)
• 5.725 GHz – 5.850 GHz (125 MHz total bandwidth)

Technologies for WLAN Transmission

Infrared LANs: This form of transmission is suitable where long-range communication is not required. Infrared signals cannot penetrate opaque walls. No license is required to operate this transmission type.

Spread Spectrum LANs: Spread spectrum transmission technology is employed, using the Industrial, Scientific, and Medical (ISM) band, which eliminates the need for licensing.

Narrowband Microwave: Microwaves are used in transmission. Some frequencies require FCC licensing while others do not, as they utilize the ISM bands.

Infrared Transmission

There are three forms of infrared transmission: direct beam, omnidirectional, and diffused.

The direct beam infrared offers the highest transmission speed. The receiver is aligned with the signal sender to form a point-to-point link. Signal range depends on the degree of focus and emitted power. Indoor environments use light-emitting diodes (LEDs), while outdoor environments require lasers.

The omnidirectional infrared configuration uses a single base transmitter station (BTS) within the LAN's line of sight. The base station is mounted at a suitable point on the ceiling and operates as a multiport repeater, broadcasting signals omnidirectionally to infrared receivers in the area.

The diffused infrared configuration uses a transmitter that fills an office space with signals. The receiver can be located anywhere in the office area to successfully receive the IR signal.

Spread Spectrum LANs

This arrangement uses a multiple-cell configuration. Each cell is assigned a unique center frequency within a specific band to avoid signal interference. Two primary methods are used: frequency hopping and direct sequence modulation.

The frequency hopping method uses signals that jump from one frequency to another within a specific bandwidth. The transmitter listens to a channel and, upon detecting idle time, transmits the packet across the full channel bandwidth. If a channel is occupied, the transmitter hops to the next channel, and the process repeats. Both transmitter and receiver share the same hopping behavior.

In direct sequence modulation, a wide frequency band and Code Division Multiple Access (CDMA) are used. Signals from multiple units are transmitted across a range of frequencies at relatively low power. Each transmitted signal carries a code that allows the receiver to identify the appropriate signal from the sending unit. This frequency falls within the ISM band.

Narrowband and Microwave LANs

This type of LAN uses narrowband microwave frequencies for signal transmission. Most equipment in this range requires FCC licensing and uses 18.82–19.205 GHz of the radio spectrum.

Licensed narrowband RF uses cell configurations in which adjacent cells employ non-overlapping bandwidths within the 18 GHz band. This scheme guarantees interference-free communication. Communication channels are highly encrypted to prevent unauthorized data interception (eavesdropping).

Unlicensed narrowband RF also operates within the ISM spectrum and may be used for transmissions of less than 0.5 watts.

WLAN Topologies

WLAN uses three main topologies:

1. Basic Service Set (BSS)
2. Independent Basic Service Set (IBSS)
3. Extended Service Set (ESS)

These can be further classified into two operational modes: ad hoc and infrastructure modes.

WLAN Security Threats and Vulnerabilities

WLAN systems are not entirely safe from threats. WLAN attacks aim to compromise the confidentiality, integrity, and availability of the system and its data, and can take the form of passive or active attacks.

Passive attacks involve unauthorized access to the WLAN for the purpose of traffic analysis, eavesdropping, or data modification. Passive attacks are difficult to detect because data is often unaffected, making prevention measures such as encryption more effective than detection alone.

Active attacks involve unauthorized access to WLAN resources for the purpose of malicious data modification or disruption of network service, thereby jeopardizing system availability.

The security risks identified include:

1. WLAN network detection
2. Disruption
3. Radio frequency signal limiting
4. Interference
5. Data interception
6. Denial of service
7. Compromised devices
8. Illegal access point deployment
9. Insider threats
10. Unauthorized network access

Corresponding mitigation techniques address each of these vulnerabilities at varying levels of risk. Key areas requiring mitigation include: RF signal propagation vulnerabilities, RF interference and disruption, unauthorized system access, data interception, denial-of-service attacks, compromised network devices, rogue access point deployment, and insider threats.

Conclusion

CyberTrans should upgrade its services to meet current industry standards of compliance. A thorough risk assessment is essential to ensure that systems remain operational 24 hours a day. By adopting WLAN, VoIP, fiber optic connectivity, and a secure hosting solution — and by implementing appropriate security measures for each — CyberTrans Ltd. can achieve a cost-effective, flexible, and secure technology infrastructure to support its relocation and future growth.

References

Bruce, W. R. (2002). Wireless LANs End to End. Ron Gilster (ed.). John Wiley & Sons.

Burell, J. (2002). Wireless local area networking: Security assessment and countermeasures: IEEE 802.11 wireless networks. Retrieved 22 March 2011, from

Cisco. (n.d.). Cisco HWIC-AP WLAN Module for Cisco 1800 (Modular), 2800 and 3800. Retrieved from http://www.cisco.com/en/US/products/ps5949/products_data_sheet0900aecd8028cc7b.html

Cisco. (2003). 2003 Wireless LAN Benefits Study. Retrieved from

Cisco. (2005). Cisco 7920 Wireless IP Phone Design and Deployment Guide. Retrieved from

Materna, B. (2009). VoIP Security Best Practices. Presented at Miami Beach Convention Center, 04/02/2009. Retrieved from http://images.tmcnet.com/expo/east-09/presentations/u303-materna-voipshield.ppt

Methos Consulting. (2011). WebTMC: A WWW server dedicated to Owasys systems. Retrieved from http://www.methosconsulting.co.uk/index.php/component/content/article/71-atn2

PC Magazine. (n.d.). Risk assessment. Retrieved from

Sunday, N. A. (2008). Wireless Local Area Network (WLAN): Security risk assessment and countermeasures. Retrieved from

Teare, D., & Paquet, C. (2005). Campus Network Design Fundamentals. Cisco Press.