Specifications for 10 Mbps IEEE 802.3 (Ethernet)

[Inigo]

1. 10base5 Specification: Use coaxial cable, bus topology, digital signage Manchester, maximum length of cable segment (between each pair of repeaters) is 500 meters, there is only one possible path between two repeaters.
2. 10Base2 specification: similar to above but with thinner cable and less expensive.
3. 10Base-T specification: use shielded twisted pair cable, while allowing a shorter distance, star topology, due to the type of cable, the maximum allowed about the 100 meters.
4. 10Ancha36 Specification: uses coaxial cable and broadband, cable 2000 meters, phase shift keying, differential coding.
5. 10Base-F specification fiber, Manchester encoding.

[Suzane]

These networks use base band sensitive to the carrier and collision detection. Some use broadband. The most widely used standard is the IEEE 802.3. In these networks, there is no set time media access but any station can access it at random. The roads are competitive type. The oldest technique used is the ALOHA, which is that if a station wants to transmit a frame, do it and wait long enough for the destination station you time to confirm the arrival of the plot. If you do not get confirmation at the time, the station resends the frame. This process is repeated until either receive confirmation or have tried a number of times without getting confirmation. The receiving station receives the frame and if it detects no error (by means of codes) sends a confirmation. It can happen that two frames are interfering (collision) and then the two are rejected, ie the receiver does not send confirmation.

[GunFighter]

ALOHA system, although very simple, allows very few burdens on the network because if there are many frames circulating at the same time, the probability of interfering (and are wrong) is great. The efficiency of ALOHA is large when the distance between stations is limited, and that could be implemented a mechanism to ensure that all stations stop transmitting when a story circulated by the network (and the wait would be too small to be walking distance). A more sophisticated technique is called CSMA. That is, with CSMA, the station wishing to transmit listens to the medium to see if there is already a plot in it, and if none issued its plot and wait for confirmation to make sure it has reached its destination correctly.

[Broot]

Collisions only occur if two stations broadcast frames at almost the same instant. To avoid the latter inefficiency, CSMA ago:

1. The sender transmits if the line is free and if not, apply 2.
2. If the medium is busy, wait until it is free.
3. If a collision is detected, the sender sends the detected interference signal for all stations know the collision and stop transmitting (to stop crashing).
4. After issuing the interference, it waits a bit and re-emit the plot.

Thus, CSMA only wasted the time it takes to detect a collision. Depending on the technique of transferring the collision detection changes.

[FlayoFish]

This method is that there is a small packet called a witness, which flows through the network when no station is transmitting. When a station wants to transmit, when you get the witness, catch it, it changes a bit and adds the data frame. Then sends the plot obtained at your destination. As the witness is gone, the other stations can not transmit. When the frame sent the complete circle to the net, is caught again by the issuer and this introduces a new witness in the network. Thus, it is possible that another station can broadcast. For low network load, this system is inefficient, but for high loads is similar to the circular rotation, efficient and equitable system. A serious drawback is that you lose control, in which case the whole network is blocked. The bits that are modified in the ring indicate whether the frame attached to the ring has reached its destination, if it has not arrived or have arrived but not copied. This control information is very important for the functioning of the system.

[Rebella]

The plot consists of a subject field plot and field priority of the plot itself, plus other control fields and data errors. This standard allows the possibility of using priorities. The algorithm is:

1. A station wishing to transmit must wait a witness with lower priority than its own.
2. If the sender detects a data frame, if its priority is higher than the reserve, put your priority in a field subject to the plot. If you received is a control frame if the priority is greater than the reserve and that of the witness, put their priority in the booking area of the witness, which was eliminated.
3. When an issuer gets the witness, put their priority in the priority field of control and set to 0 the subject field control.

[Alondra]

FDDI does not contain bits of priority or reservation. FDDI, when it receives a token frame, the gate and not repeated until it has sent its data frames (so it is not possible to implement priorities in this way). FDDI liberalization sends a witness when it sent its last data frame, even if not received back the ring. By means of specific bits in the frame. the sender can detect that the frame has been received, that has not been successful or that the destination station does not exist. To allow some form of network sharing between all stations, they can apply for inclusion in a rotation synchronous access time (same for all stations are "discharged" in this system.) In addition, maintaining the type of asynchronous access token. The ring topology. It uses fiber optic or twisted pair shielded or unshielded.