Troubleshooting Wireless Connectivity
Some of the common problems faced by users in a wireless connection are discussed as follows:
Reflection: Wireless signal suffers from interference due to the mirrors or shiny surfaces. Mirrors or shiny surfaces can reflect the signals which may delay transmission.
Refraction: Wireless signal suffer from interference due to the glass or water. Glass or water can cause the wireless signals to bend and take a different path which results in data rate drop.
Absorption: Absorption can be defined as the amount of signal strength reduced by walls and windows. Whenever a wireless signal passes from a wall or a window, some amount of energy is lost. To prevent wireless signals from absorption, organisations should use ceiling mounted APs.
Incorrect Antenna Type: In case of wireless connection, one of the most common area where generally error occurs is antenna. Various issues such as short range and low signal strength at the receiver site may arise in wireless communication due to the following factors:
- Inaccurate selection of antenna type: Incorrect antenna type may give rise to several issues and errors in a network. Therefore, it is important to select the right antenna type while setting up a network.
- Incorrect antenna placement: There should be adequate amount of space between antennas. For example, antennas can be set up at one-quarter of a wavelength (approximately 5 inches at 600 MHz). Further, user should maintain a line of sight between the transmitter and receiver antenna while setting up an antenna. In addition, any object of interference should be kept away from the location of the antenna.
- Inaccurate cable type: A minimum length of the appropriate low-loss cable equipped with suitable connectors will give the best results. Further, due to increase in number of losses at higher frequencies, UHF systems may require special cables.
Channel Overlap: The 2.4 GHz band is widely used in wireless communications. The IEEE standard has defined 14 separate channels in the 2.4 GHz band. These wireless channels are designated by radio communication frequencies. These channels facilitate communication among Wi-Fi network resources such as client devices and broadband routers. Further, wireless enabled devices can also automatically adjust their channel numbers.
The bandwidth of each channel in the 2.4 GHz band is only 20 MHz approximately. Further, the distance between centre frequencies of each channel is 5 MHz. Thus, overlapping occurs as all the channels have to squeeze into 100 MHz of available bandwidth.
In older to avoid Overlapping of channels, some users prefer to use non-overlapping channels. There are three non-overlapping channels namely, channel 1, channel 6 and channel 11. These channels have enough frequencies which separate them from each other and avoid overlapping.
power levels: Sometimes, it is necessary to adjust the power level used by an AR Increased power level can cause interference with cells which can result in clients being able to listen AP but unable to communicate with them. Overcapacity: Capacity of a network can be defined as the maximum amount of data that can be transmitted among multiple network nodes. As the bandwidth requirement is increasing day by day, network designers need to increase the capacity of the network. Thus, it is important to maintain a proper capacity of the network as per the requirements of the users. If the network has a huge amount of data which is beyond its capacity, it leads to an issue of overcapacity. Further, an overcapacity may cause problems such as slow performing and unstable network.
Interference: Interference can be defined as anything that disrupts a signal in between the source and the receiver. In wireless network, interference is mostly occurs when two wireless devices transmit the signals at the same frequency or in the same channel. In wireless devices, air is the common medium so most of the wireless devices such as video surveillance systems and microwaves transmitting in same bands are prone to interference. Interference mostly depends on the strength of transmission and the distance with the interferer.
Distance Limitations: The energy of a signal reduces as it moves from the access point to the receiving node. Therefore, each wireless equipment has a limited range to transmit signals. However, additional equipment such as repeaters can be used to increase the range of wireless network devices.
Frequency Mismatch: Frequency mismatch occurs when two or more wireless devices use the same frequency in the network. For example, a frequency mismatch may occur when a cordless phone and microwave oven may use the same frequency and network.
Wrong SSID: While troubleshooting a wireless network, a user may face a wrong SSID issue. In such case, a user should check the network list of his router and if the SSID does not appear in the list, SSID broadcast should be enabled on the router. Further, SSID can be added manually by a user.
Wrong Passphrase: Passphrase can be defined as the grouping of characters which are used to control and manage access to a computer network, program and database. Wrong passphrase is a type of error which indicates that the passphrase entered is incorrect. Further, a wrong passphrase error results in authentication failure.
Security Type Mismatch: Security type mismatch occurs when a user enters wrong security type while configuring wireless security settings. Further, a user can configure security type in the wireless network properties by selecting WEP, WPA, or WPA2. However, it is recommended to use WPA2 as it is more secured than other security types.
Signal to Noise Ratio (SNR): SNR is the ratio of signal strength to the noise present in the connection. It is measured in terms of decibels (dB). The term “noise” specifies unwanted frequencies that interfere with the wireless network.