Is it possible to simultaneously transmit with a basic ring topology? In a basic ring topology can I have more than one token? Is Active Monitor will remove tokens if I have more then one? Can you give some useful link about it?
Well it depends on what kind of ring we are talking about. If the ring is able to use multiple wavelengths, such as a MultiTokenRing, then it can have one token per wavelength, and thus multiple nodes can transmit data at the same time.
For a simple ring, I think Wikipedia has a clear answer:
When no station is transmitting a data frame, a special token frame circles the loop. This special token frame is repeated from station to station until arriving at a station that needs to transmit data. When a station needs to transmit data, it converts the token frame into a data frame for transmission. Once the sending station receives its own data frame, it converts the frame back into a token. If a transmission error occurs and no token frame, or more than one, is present, a special station referred to as the Active Monitor detects the problem and removes and/or reinserts tokens as necessary (see Active and standby monitors). On 4 Mbit/s Token Ring, only one token may circulate; on 16 Mbit/s Token Ring, there may be multiple tokens.