A Linear Network topology is ideal for providing communications in systems that naturally require stations deployed along a line. Some of the applications are:
Railway wayside communicationsPipeline communications
Highway roadside communications
Long links that requires multiple repeaters between the end pointsThe figure shows the general topology of a Wireless Linear Network. Each node in the network has at most two neighbors with which it can communicate directly. Each station in the network uses a single radio, the
PulsAR-24027 Wireless Ethernet Bridge , which comes equiped with a two antenna ports.
The following are some characteristics of the AFAR wireless linear network:
Each node consists of a single radio with two RF ports. Typically a node is deployed with two directional antennas pointing at each of the node's neighbors.
Each node has an Ethernet port for connection to a LAN or directly to the user equipment.
A packet can enter the linear network at any node, through the Ethernet port. If the packet is addressed to a station at a remote LAN, the radio transmits the packet to its right or left neighbor as necessary. The packet may then go through multiple hops in one direction until it exits the linear network at its destination.
When a packet goes through multiple hops, the packet does not show up at the local LANs of the intermediate nodes.
The network supports broadcast packets, which are transmitted, left and right, until they show up at every local LAN.
The behavior described in the above paragraphs is self-learned. No user configuration is required.
All radios are peers, there is no master radio providing synchronization, therefore no single point failure.
If a node fails, the two segments of the original linear network continue to operate as two separate linear networks. Once the failed node is reactivated, the two networks automatically merge into one.
The Linear Network topology is designed to be an integral part of the Afar
SPAN Network which can synchronize the transmissions of co-located radios . Therefore the nodes can be co-located with AFAR radios running in Point-to-Multipoint and Point-to-Point without generating self-interference.
Konvoi ke Bukt Beirut bersama rakan-rakan untuk melaksanakan misi khas bertukar menjadi misi 4x4. Pelbagai kejadian melucukan berlaku dan menjadi kenangan kami sampai bila-bila. Pak Presiden Mares Kelantan (9W2BCH), 9W2JYT, 9W2TYT, 9W2JPC, 9W2DCO dan 9W2MYD serta saya sendiri menimba pengalaman yg benar-benar mencabar. Masakan tidak, kami langsung tidak bersedia untuk menghadapi situasi ini kerana perancangan kami adalah untuk melihat tapak yg sesuai untuk pemasangan repeater. Namun, kami belum berpuashati... kami akan pergi lagi.. dan saya yakin rakan-rakan juga mahu pergi sekali lagi.. dengan kelengkapan yang cukup dan bekalan yang cukup...
