Wi-Fi (Wireless Fidelity) is a trademark of the Wi-Fi Alliance. Wi-Fi most commonly uses the 2.4 gigahertz (12 cm) UHF and 5 gigahertz (6 cm) SHF ISM radio bands. Devices include laptops, PDA, smartphones can access to internet with the wireless connection. Wi-Fi provide fast, broadly covered internet access with low cost in equipment construction, such that it has become the most popular way to access the internet. The most popular industry standard for the Wi-Fi wireless network is IEEE 802.11. From the early 802.11a, 802.11b, 802.11g standard to current 802.11ac, 802.11ad (54Mbps), the data transmission speed is still increasing.

It has been nearly 15 years since Wi-Fi was first introduced in Hong Kong. What made WiFi truly become widespread in Hong Kong was some fixed network operators started to provide 200 Wi-Fi hotspots in coffee shop since 2003. After that, many computer and consumer electronics manufacturers have already incorporated Wi-Fi feature into their products. Notebook computers, smartphones, PDA and handheld electronic game devices, are examples that have built-in Wi-Fi connectivity. Moreover, a wide range of household equipment such as television, set-top boxes, light bulbs, some digital cameras and photo frames are also included WiFi connection. The built-in Wi-Fi functions in digital devices made the development of Wi-Fi rocketed.

In March 2004, Wi-Fi service was available in the entrances of some MTR platforms. At the same time, one of the wireless network service provider setup around 200 Wi-Fi hotspots in high-end restaurants and other places in June 2004 and 2005. The number of AP (Access points) in Hong Kong was thus immensely increased. Some service providers started to provide Wi-Fi hotspots at designated convenience stores and payphones in 2007. In January 2008, some internet service providers started to offer Wi-Fi services in housing estates, which made Wi-Fi service become more accessible for public.

Furthermore, HKSAR Government officially launched Government Wi-Fi Programme (GovWiFi) in July 2007, which provided about 600 more free WiFi hotspots with encrypted connection at designated government premises, including public libraries, public enquiry service centers, sports venue etc., public can access to internet complimentarily for study, leisure or accessing online banking, trading activities. Public and private sectors were joined together to build Hong Kong into a ubiquitous network city.

Since data is transmitted through radio waves, it is prone to security issues and sensitive information can possibly be usurped by others when using WiFi connection. Hackers can also take advantage of the security loopholes if the protection for the Wi-Fi connected devices is not up-to-date. To prevent personal information from being hacked, users should employ certain level of security measures when connecting to Wi-Fi, such as utilizing encrypted wireless security technology - Wired Equivalent Privacy (WEP) and Wi-Fi Protected Access (WPA) when using Wi-Fi. Temporal Key Integrity Protocol (TKIP) and Advanced Encryption Standard (AES), which are designed for strengthening Wi-Fi security. TKIP standard is compatible with existing network hardware complied with IEEE 802.11 standard. Through upgrading firmware and software, different encryption keys will be added to all network packets for data transmission to increase the security level of encryption. For AES, it is a chip-based security measure using block ciphers and efficient for encrypting data transmission and data storage for software and hardware.

Still, with the rapid development in hacking technique, protecting ourselves from cyber-attack is never an easy job. Some relatively secure protection might become vulnerable one day as time goes by. When enjoying the convenience to access internet through Wi-Fi, it is also crucial for us to keep in mind that hacker can easily usurp information through different hacking tactic. The worst scenario is if a network is compromised, attacker can achieve a high level of penetration into the network, and take over personal data for illegal use.

In order to raise public awareness in Wi-Fi security, Hong Kong Wireless Technology Industry Association (WTIA) started SafeWiFi.hk and set up the thematic website, which includes knowledge, tips and news about Wi-Fi security and video tutorial for WiFi security setting. WTIA is also working with Professional Information Security Association (PISA) to conduct annual WiFi security survey and co-organize events to promote Wi-Fi security for the public.