Data Link/Network Layer - Samsung OfficeServ 500 Service Manual

OfficeServ 500 Wireless LAN Service Manual/Ed.00
3.3

Data Link/Network Layer

The flexibility of network construction, a strength of wireless LAN is fully
considered in IEEE802.11 and is expressed in network models. Network models
defined in IEEE802.11 are categorized into an ad hoc network and Infra network.
Ad Hoc Network
The Ad hoc network consists of terminals only and is based on direct communication
between terminals. Its operation is to be recognized by Zone ID called BSS ID
logically. The Ad hoc network is suitable to collaborate through information sharing
or networks using wireless LAN where networks are not equipped.
Figure A.1 Data Link/Network Layer of WLAN-Ad hoc Network Model
Infra Network
Infra network is able to communicate with terminals that have at least one Access
Point(AP) and are within areas other than the areas of Infra network. The models of
the infra network has a Distribution System(DS), which serves as media.
DS is an abstract concept and is included in network models. It distributes the definition of
network as BSS ID.
Specifications do not describe the implementation method of distribution. However,
wireless LAN connected to the DS is called AP in the specifications. Management
protocols that operate wireless LAN using infra network are defined in many ways.
AP manages the operation of the zone and makes master and slave relationship
among terminals in the zone. For this, AP sends beacon to the operating zone.
It is impossible to send user data unless all terminals perform association to AP.
© SAMSUNG Electronics Co., Ltd.
User 1
Beacon and Association
Beacon refers to sending code sending necessary information to wireless LAN.
Association means that terminals are connected to one AP.
Annex A. WLAN(802.11b/DSSS) Specifications
User 2
Annex A-5