- Aloha, also called the Aloha method, refers toa simple communications scheme in which each source (transmitter) in a network sends data wheneverthere is a frame to send. If the framesuccessfully reaches the destination (receiver), the next frame is sent. If theframe fails to be received at the destination, it is sent again. This protocol wasoriginally developed at the University of Hawaii for use with satellite communication systems in the Pacific.In a wireless broadcast systemor a half-duplex two-way link, Aloha works perfectly. But as networks become morecomplex, for example in an Ethernet systeminvolving multiple sources and destinations that share a common data path,trouble occurs because data frames collide (conflict). The heavier thecommunications volume, the worse the collision problems become. The result isdegradation of system efficiency, because when two frames collide, the data contained inboth frames is lost. To minimize the number of collisions, thereby optimizing networkefficiency and increasing the number of subscribers that can use a given network, a schemecalled slotted Aloha was developed. This system employs signals called beacons that are sentat precise intervals and tell each source when the channel is clear to send aframe. Further improvement can be realized by a more sophisticated protocol called Carrier Sense Multiple Access withCollision Detection (CSMA/CD).
 |
Learn more about Network Administration |
| Networking FAQ: These FAQs for networking will help you learn networking basics. |
| Network user management: Use this guide to learn how to manage problem users on your network -- from un-savvy Internet novices to toxic bosses -- to keep your network secure. |
| Troubleshooting -- 'Network Know-How' Chapter 17: Troubleshooting, Chapter 17 of 'Network Know-How,' shows tools and methods that identify and solve network problems. Use this chapter as a tutorial to fixing computer connections. |
| Network management frameworks: FCAPS and ITIL: Network management is a complex topic. Thus far, two frameworks exist that can be of some use for understanding and taming network management: FCAPS and ITIL. |
| Networking podcasts: Listen to our networking podcasts and learn more about technologies you need to know to keep your network running smoothly. |
| The IT Guy: Networking comics: In our networking comic series, the IT guy and his office coworkers encounter day-to-day network challenges. |
| LAST UPDATED: |
06 Sep 2005
|
 |
Do you have something to add to this definition? Let us know.
Send your comments to techterms@whatis.com
|

 |
More resources from around the web:
|


');
// -->


 |
 |
|  |
RELATED GLOSSARY TERMS
| Terms from Whatis.com − the technology online dictionary |
 |
availability
(SearchNetworking.com)
1) In a telephone circuit, availability is the ratio between the time during which the circuit is operational and elapsed time.
2) In a network...
|
 |
carrier detect
(SearchNetworking.com)
|
|

|