The ubiquitous networking technology is still in its very early stages, and there are numerous issues that need to be addressed before achieving a perfect operating environment. One of the major issues is to maintain interoperability between different networking technologies. For example, an office employee may have a Bluetooth device that connects with her laptop, use a wireless LAN based on 802.11g, a wireless WAN based on 3G, and a wired connection using ADSL. To maximise the benefits from a ubiquitous networking environment, these various technologies should be able to communicate without any disruptions. Additionally, processing power of mobile devices and issue of security is one of other concerns for true ubiquitous networking environment.
Currently, significant research emphasis is given to the security and middleware side of ubiquitous networking to address this, and it is highly related with improvements in the processing power of mobile devices.
Network selection and billing
Selection of networks in a ubiquitous networking environment is one of the main operating issues with this technology.
For example, in a ubiquitous networking environment, a cordless phone may substitute your mobile phone when you are outside the house. Choosing the best network based solely on the user requirements complicates the selection of the “ideal” network for a particular connection time and location. The user-initiated selection of a provider also generates the issue of billing. Currently customers “subscribe” to the desired services, and get billed based on the usage. However, in a ubiquitous networking environment, there is no need to “subscribe” for a desired service, but rather users have the capability to employ ad-hoc type services when needed as depicted in the illustration below. This adds complexity to existing billing systems however these requirements need to be addressed to achieve a truly ubiquitous networking environment.
The ubiquitous networking environment creates new challenges in security and requires development of new approaches to address both existing and new security problems. Heterogeneous networking environments add a complexity to existing security mechanisms, and different techniques needs to be developed to ensure optimum levels of security in the ubiquitous networking environment.
Middleware
The advancements in handheld devices are one of the key drivers of ubiquitous networking, and these devices are improving their capabilities at exponential rates. However, due mainly to their size restrictions, these devices suffer from a number of limitations. These limitations include but are not limited to: inadequate processing capability, restricted battery life, limited memory space, slow expensive connections, and confined host bandwidth.
To address these limitations, middleware can play an essential role. For example, rather than delegating processing responsibility to the light-weight handheld devices, core processing can be performed by the middleware applications. Currently developed middleware applications are capable of providing services such as security, data backup services, resource discovery services, and ad-hoc communication services, to list a few.
Security
Security has always been a critical issue within the area of networking, and this is not an exception in ubiquitous networking environments. In fact, security in this type of environment requires more emphasis than what has been perceived in traditional networks. The convenience of handheld devices, such as PDAs, means that people are storing personal data on these devices, which means that more stringent security mechanisms to protect this data are required. The typical characteristics of handheld devices also create security concerns, such as;
• Mobile communications uses a public transmission medium, which creates opportunity for hackers to eavesdrop communications more easily than with secured private connections.
• Mobile devices are vulnerable to theft, loss, and corruptibility.
• Processing power limitations on mobile devices can imply restrictions on security features (e.g., Algorithm selection).
To address these issues, various methods are proposed. The common approach is the use of security protocol, middleware, and hardware-driven security.
