第1个回答 2006-08-14
The area net( WLAN) of the line bureau is the outcome that the calculator network and lead-ins corresponds by letter the technique to combine together.It makes use of the radio frequency ( RF) technique, with many addresses of lead-in believe the way of way carry out the correspondence between calculator.The IEEE releases the standard IEEE802.11 of WLAN to rule the physics layer and mediums to visit the technical specification of control the son layer( MAC).802.11 area net MAC layers of the lead-in bureau contain two kinds of correspondence methods, a kind of is the distribute type coordination( DCF), another is a kind of is to order the coordination method( PCF).The distribute type coordination( DCF) is according to have the conflict examination to carry a many roads of interception interview method( CSMA/ CA).The method( PCF) of order the coordination mean to adopt a 询 method, the lead-in connects in to order the equipments periodic ground to send out the signal test, passing to test to identify with each lead-in equipments for the network, the network management parameter etc. carries on hand over with each other.Increase along with the lead-in network customer, business put forward in the wired network request, such as video frequency, speech...etc. solid hour the business is in the WLAN also good arrive satisfy.These solid hour businesses request the WLAN MAC layer and can provide the set of dependable cent to deliver, postponing while deliver low and tremble to move small, make it the demand of the contented QoS( the Quality of Service)
第2个回答 2006-08-14
哇 好了不起 你们都是几级的?
什么水平啊 真佩服
第3个回答 2006-08-14
WLAN(Wireless Local Area Network) is the product of computer network technology and wireless communicatin technology's combination. It takes advantage of the FR technology,realizing the computers communicatin by wireless multi-site access.The IEEE releases the standard IEEE802.11 of WLAN to rule the physics layer and mediums to visit the technical specification of control the son layer( MAC).Having two kinds of communication modes 802.11 not having the thread local area network MAC layer , one kind is distributing type coordination ( DCF ) , and another kind is that the point coordinates the method ( PCF ) . Distributed coordination (DCF), is based on the carrier with conflict detection monitoring multiplexed visit methods (CSMA/CA). Points coordinated manner (PCF) refers to the use of polling, wireless access point equipment to send signals cyclical test frame by frame with the wireless test equipment for network identification, such as network management parameters for the world. With the increased wireless network users, the cable network operational requirements, such as video, voice and other real-time operations, but also in WLAN met. These real-time operational requirements of the WLAN MAC layer to provide a reliable transmission, transmission time low and shake small to meet QoS (Quality of Service) needs.
第4个回答 2006-08-14
Wireless LAN (WLAN) and wireless computer networks is a product of the combination of technologies. It uses radio frequency (RF) technology, wireless multi-site access to the means to achieve communication between computers. IEEE WLAN standards IEEE802.11 provides a physical layer and media access control sublayer (MAC) specifications. 802.11 wireless LAN MAC layer, there are two forms of communication, is a distributed coordination (DCF), is another point of coordination (PCF). Distributed coordination (DCF), is based on the carrier with conflict detection monitoring multiplexed visit methods (CSMA/CA). Points coordinated manner (PCF) refers to the use of polling, wireless access point equipment to send signals cyclical test frame by frame with the wireless test equipment for network identification, such as network management parameters for the world. With the increased wireless network users, the cable network operational requirements, such as video, voice and other real-time operations, but also in WLAN met. These real-time operational requirements of the WLAN MAC layer to provide a reliable transmission, transmission time low and shake small to meet QoS (Quality of Service) needs. 就这样
第5个回答 2006-08-14
The wireless bureau area net(WLAN) is the outcome that calculator network and wireless corresponds by letter a technique to combine together.It makes use of a radio frequency (RF) technique, carrying out the correspondence of of calculator by wireless' many address letter's way of the way.The IEEE released the WLAN standard IEEE802.11 to rule physical layer and medium to visit control son the technical specification of the layer(MAC).802.11 contain two kinds of correspondence methods, 1 kind is a distribute type coordination(DCF), another 1 kind orders a coordination method(PCF).Distribute type coordination(DCF) is according to have a conflict examination to carry many road interview of an interception a method(CSMA/CA).The method(PCF) of ordering the coordination means the adoption round inquires a way, the wireless connects in to order equipments periodic ground to send out a signal test, passing a test to identify for the network with each wireless equipments, network management parameter's etc. carry on handing over with each other.Because the wireless network customer increases, putting forward in the wired network of business request, such as video frequency, speech...etc. solid hour the business is in the WLAN also good arrive satisfy.These can provide a dependable cent set to deliver, postponing while delivering low and tremble to move small, make it the demands of contented QoS(Quality of Service).