Modes of operation.

Modes of operation.

wireless network interface controller WNIC is a network card which connects to a radiobased computer network, unlike a regular network interface controller NIC which connects to a wirebased network such as token ring or ethernet. A WNIC, just like a NIC, works on the Layer and Layer of the OSI Model. A WNIC is an essential component for wireless desktop computer. This card uses an antenna to communicate through microwaves. A WNIC in a desktop computer usually is connected using the PCI bus. Other connectivity options are USB and PC card. Integrated WNICs are also available, typically in Mini PCIPCI Express Mini Card form.In an infrastructure mode network the WNIC needs an access point all data is transferred using the access point as the central hub. All wireless nodes in an infrastructure mode network connect to an access point. All nodes connecting to the access point must have the same service set identifier SSID as the access point, and if the access point is enabled with WEP they must have the same WEP key or other authentication parameters.

In an adhoc mode network the WNIC does not require an access point, but rather can directly interface with all other wireless nodes directly. All the nodes in an adhoc network must have the same channel and SSID.NICs are designed around the IEEE . standard which sets out lowlevel specifications for how all wireless networks operate. Earlier interface controllers are usually only compatible with earlier variants of the standard, while newer cards support both current and old standards.Wireless range may be substantially affected by objects in the way of the signal and by the quality of the antenna. Large electrical appliances, such as a refrigerators, fuse boxes, metal plumbing, and air conditioning units can block a wireless network signal. The theoretical maximum range is only reached under ideal circumstances and true effective range is typically about half of the theoretical range. Specifically, the maximum throughput speed is only achieved at extremely close range less than feet . m or so at the outer reaches of a devices effective range, speed may decrease to around Mbits before it drops out altogether.

Wireless network interface card.

Wireless network interface card.

WNICs are designed around the IEEE . standard which sets out lowlevel specifications for how all wireless networks operate. Earlier interface controllers are usually only compatible with earlier variants of the standard, while newer cards support both current and old standards.Wireless range may be substantially affected by objects in the way of the signal and by the quality of the antenna. Large electrical appliances, such as a refrigerators, fuse boxes, metal plumbing, and air conditioning units can block a wireless network signal. The theoretical maximum range is only reached under ideal circumstances and true effective range is typically about half of the theoretical range. Specifically, the maximum throughput speed is only achieved at extremely close range less than feet . m or so at the outer reaches of a devices effective range, speed may decrease to around Mbits before it drops out altogether. The reason is that wireless devices dynamically negotiate the top speed at which they can communicate without dropping too many data packets.

In computer networking, a Media Access Control address MAC address or Ethernet Hardware Address EHA, hardware address, adapter address or physical address is a quasiunique identifier assigned to most network adapters or network interface cards NICs by the manufacturer for identification. If assigned by the manufacturer, a MAC address usually encodes the manufacturers registered identification number.Although intended to be a permanent and globally unique identification, it is possible to change the MAC address on most of todays hardware, an action often referred to as MAC spoofing. Three numbering spaces, managed by the Institute of Electrical and Electronics Engineers IEEE, are in common use for formulating a MAC address MAC, EUI, and EUI. The IEEE claims trademarks on the names EUI and EUI, where EUI stands for Extended Unique Identifier.A host cannot determine a priori from the MAC address of another host whether that host is on the same OSI Layer network segment as the sending host or a network segment bridged to that network segment.