- What is Wi-Fi (Wireless Fidelity)?
Initiated by Wi-Fi Alliance, Wi-Fi is a wireless technology with 2.4GHz radio frequency for data transmission. It can be used in a wide range of wireless devices such as notebook computers, personal digital assistants (PDA), mobile phones and smart phones, to access Internet. All recognized wireless LAN technology by Wi-Fi must be approved through Institute of Electrical and Electronics Engineers (IEEE), and now, IEEE 802.11b and IEEE 802.11g are two of the available standards.
- What are the advantages of Wi-Fi wireless technology?
Within the coverage, users can fast access Internet through their own electronic devices which embedded with Wi-Fi technology. Comparing to other wireless technologies, recognized Wi-Fi products can enhance the compatibility between users terminals or access point that allows easy and stable wireless services.
- What kinds of electronic products support Wi-Fi technology?Fi技術？
As Wi-Fi service is now more popular with growing coverage and availability, many computer and consumer electronics manufacturers have already incorporated Wi-Fi function into their products. Notebook computers, smart phones, PDA and handheld electronic game devices, are the examples that have Wi-Fi functionality. In addition, some digital cameras and photo frames also include this function.
- How fast is Wi-Fi wireless network?
According to IEEE 802.11b and IEEE 802.11g, their optimal transmission speeds are 11Mbps and 54Mbps respectively. While in next generation of 802.11n standard, its optimal speed can reach 248Mbps. For other standards, such as SuperG, Afterburner, Draft N 2.0, their maximum speeds are 108Mbps、125Mbps and 450Mbps respectively. However, as they have not yet approved by IEEE, Wi-Fi wireless network would not offer these communication standards.
- How far can Wi-Fi cover in outdoor area?
Wi-Fi signals can reach 100m in outdoor area. However, it depends on the distance between users’ geographical location and Wireless Access Point. Obstacles in between two points would weaken the signal and decrease the transmission speed.
- Would Wi-Fi wireless network be interfered?
If there are some obstacles in between Wireless Access Point and users, the signal would be blocked which in turns affect the transmission speed. The effect may be varied with different materials and surface areas of obstacles. Furthermore, Wi-Fi network would also be interfered when there are other wireless networks with same frequency or electronic devices which use 2.4GHz frequency band within the coverage.
- What applications that Wi-Fi wireless network offers?
Users can access Internet through Wi-Fi network to browse webpages, manage emails, conduct video conference, internet chat or instant massagers.
- What is Service Set Identifier (SSID)?
SSID is a wireless network identity code that is also regarded as name of wireless LAN, it allows not more than 32 characters or symbols. When users have to connect to assign Wi-Fi LAN, both SSIDs must be the same. Therefore, the major function of SSID is to distinguish different wireless LAN. In Wi-Fi wireless network, SSID represents Wireless Access Point’s network name during broadcast.
- What are the two major communication modes of Wi-Fi?
The two major communication modes of Wi-Fi are ad-hoc mode and infrastructure mode. Ad-hoc mode represents communication between different user terminals. While infrastructure mode is communication between user terminals and Wireless Access Point, and it is usually used in Wi-Fi wireless Internet access.
- What is Radio Frequency?
Radio frequency refers to electric waves that may radiate to a specific room, any sound, image and data may transform and transmit to the atmosphere through radio frequency. According to the Article 2 of Radio Regulation, radio frequency is a kind of wireless communication with frequency lower than 3,000GHz.
- What is Gov WiFi?
HKSAR Government has launched GovWiFi in July 2007, to provide free wireless Internet access services to all citizens by installing Wi-Fi facilities at about 350 designated government premises including public libraries, Public Enquiry Service Centres, sports centres. With encrypted connection, general public can surf the web freely for any private Internet activity such as Internet banking or stock exchange. It aims to build Hong Kong into a ubiquitous network city.
- Where is GovWiFi located?
From early 2008 to mid 2009, government progressively starts installing Wi-Fi facilities at about 350 government premises. These premises include public libraries, Public Enquiry Service Centres, sports centres, cultural and recreational centres, job centres, community halls, large parks and Government joint-user buildings.
- How to find GovWiFi service nearby?
Simply visit GovWiFi Locator (www.gov.hk/wifi) for more details about the GovWiFi locations.
- Are the free Wi-Fi services available in public housing estates part of GovWiFi?
The free Wi-Fi services available in the public housing estates are not provided by the GovWiFi Programme. They are provided by other commercial IT service provider for public rental housing (PRH) tenants.
- Would Wi-Fi automatically switch to other commercial wireless network?
Some mobile devices would switch the Internet access service between GPRS/3G and other Wi-Fi services automatically depending on signal strength. If there are more than one wireless or mobile service available, the one with the strongest signal may be connected.
- How to avoid mobile device automatically switching from Wi-Fi to other commercial wireless network?
To avoid dispute on connection service charges, users should be aware of the data services that are using and the characteristics of mobile devices. To avoid connecting to chargeable GPRS/3G or Wi-Fi services unintentionally, users should turn off the Internet access feature of GPRS, 3G and Wi-Fi, as well as disable the feature of automatic connection to these networks.
- Is it safe to use the Smartphone as a hotspot?
It is safe to use only if you are using manufacturer supported Smartphone Operating Systems and configuring the hotspot with good password protected WPA2-PSK.
- Is WEP secured for Wi-Fi connection?
Wired Equivalent Privacy (WEP) is one of the encryption mechanisms of IEEE 802.11 standard, which is used to protect data privacy during transmission through network. However, many Internet experts criticized WEP is not secure enough, and it is gradually replaced by other new encryption methods, such as WPA or WPA2.
- How to ensure secure data transmission through Wi-Fi network?
To ensure data privacy during transmission, users should encrypt their network. WEP, WPA and WPA2 are the common standards. Authorized Wi-Fi user terminals have to input encryption key before utilizing resources available on Wi-Fi network.
- What are TKIP and AES?
Temporal Key Integrity Protocol (TKIP) and Advanced Encryption Standard (AES) 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 data transmission packets in order to increase security of encryption. AES is a kind of chip-based security measure using block ciphers. Such an advanced encryption standard would be more effective when using hardware or software to communicate or store data.
- What is Wi-Fi Protected Setup standard?
Wi-Fi Protected Setup (WPS) is a certified standard officially launched in 2007, consumers can encrypt Wi-Fi network through easy and secure way, such as Pin Input Configuration (PIN)、 Push Button Configuration (PBC)、USB Flash Drive Configuration (UFD). Within the certification, it guarantees IEEE 802 wireless LAN products can mutually operate.
- How to prevent Wi-Fi router being detected by others?
By setting up wireless LAN access point or router appropriately, such as switch off the broadcast function in service set identifier (SSID), to disable detection of Wi-Fi network under general situation.
- What is Wi-Fi Protected Access (WPA)?
In order to resolve the security vulnerability of Wired Equivalent Privacy (WEP), the Wi-Fi Alliance launched two new wireless network security standard WPA and WPA2, with personal and enterprise version available.
- What is the difference between personal and enterprise version of WPA/WPA2?
In WPA, enterprise WPA is meant for use with an IEEE 802.1X authentication server, which distributes different keys to each user. It also allows "Pre-Shared key" (PSK) that every user shares the same key, which is named as personal WPA or WPA2.
- How to protect intrusion from hacker at home Wi-Fi?
Data security at home Wi-Fi network should not be neglected, users should always enable secure encryption in every Wi-Fi network. In addition, users are encouraged to use new encryption technologies, such as WPA/WPA2, and activate MAC Address filter function to allow only authorized Wi-Fi client terminals using Wi-Fi resources.
- What should be aware when using unencrypted Wi-Fi hotspot?
As data is not encrypted, it is at high risk to transmit data and is not recommended to use such a kind of Wi-Fi network. Do not read private email, perform online transaction or use Internet banking through unencrypted Wi-Fi network if it is not necessary.
- What preventive measures should be taken when using public wireless Internet access?
Users should ensure computer has already installed firewall, anti-virus and anti-spy programs. Users should also ensure these security programs are working properly all the time and have regular update on definitions.
- Would it be safer to use Wi-Fi with VPN service?
Virtual Private Network (VPN) is a transmission channel set up for using encryption on Internet. It offers higher security level of data transmission for more secure Wi-Fi network.
- Is it at high risk when using unknown Wi-Fi hotspot?
Users should always be aware of unknown Wi-Fi hotspot. Criminals may capture all key-in data, such as personal account and password, or even other information available in the computer.
- Is it secure to access Internet through GovWiFi?
Users can make use of encrypted connection available in GovWiFi to encrypt the Wi-Fi network. It can protect all data during transmission as well as information in the personal computer.
- How to set up encrypted connection in GovWiFi?
Please refer to the categories of encryption technology that the Wi-Fi wireless network client terminal supported and establish relevant settings. Visit http://www.gov.hk/en/theme/wifi/guide/index.htm for more details.
- Is there any authoritative Wi-Fi security study?
Since 2003, Hong Kong Wireless Technology Industry Association and Professional Information Security Association have jointly conducted annual Wi-Fi wireless security survey in Hong Kong. General public can visit both websites for survey results.
- Any tips for checking email through Wi-Fi hotspot?
Using webmail system with Secure Socket Layer (SSL) data encrypted protocol that can encrypt data transmitted, for example, enter https://mail.google.com instead of http://mail.google.com to login.
- Do Wi-Fi facilities in Hong Kong meet the health and safety standard?
The Office of the Telecommunications Authority (OFTA) has adopted "International Commission of Non-Ionising Radiation Protection Guidelines" to limit the emission of non-ionising radiation within specified RF in order to protect the health of workers and the public. In addition, all Wi-Fi products sold and used in Hong Kong must comply with the standards specified in the Guidelines.
- Would Wi-Fi be harmful to human health?
Radiation from Wi-Fi network’s radio frequency is far lower than mobile phone. Meanwhile, there is no evidence that Wi-Fi is harmful to human health according to World Health Organization.