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📜  早期和延迟令牌发行之间的区别

📅  最后修改于: 2021-08-27 04:48:39             🧑  作者: Mango

先决条件–令牌环

1.早期代币发行：

  • 发送方在释放令牌之前不会等待数据包完成旋转。数据一经发送，令牌即被释放。
  • 环中存在多个数据包。
  • 不如延迟令牌发布可靠。

2.延迟发行令牌：

  • 在这种情况下，发送方发送数据包并等待，直到整个数据包都经过环的往返并返回为止。当发送方收到整个数据包时，它将释放令牌。
  • 实例中环上只有一个数据包。
  • 比早期代币发行更可靠。

早期和延迟令牌发行之间的区别：

Early Token Release Delayed Token Release
Sender does not wait for the data packet to complete revolution before releasing the token. In this, the sender transmit the data packet and waits till the time the whole packet takes the round trip of the ring and return to it. 
Token is released as soon as the data is transmitted. When the whole packet is received by the sender, then it releases the token.
At an instance, Multiple packets are present in the ring. There is only one packet in the ring at any instance.
Less Reliable as compared to Delayed Token Release. More Reliable as compared to Early Token Release.

Token Holding Time (THT) = Tt

where, Tt = transmission delay

Token Holding Time (THT) = Tt + Tp

where, Tt = transmission delay,
Tp = propagation delay
Collision is possible as multiple packets are present in the ring. Collision is not possible as there is only one packet in the ring at any instance.
Cycle Time = Tp + N * (Tt)
where,
Tt = transmission delay
Tp = propagation delay
N = No. of stations in ring		 Cycle Time = Tp + N*(Tt + Tp)
where,
Tt = transmission delay
Tp = propagation delay
N = No. of stations in ring
Efficiency = (N * Tt) / (Tp + N * (Tt))
where,
Tt = transmission delay
Tp = propagation delay
N = No. of stations in ring		 Efficiency = (N * Tt)/(Tp + N*(Tt + Tp))
where,
Tt = transmission delay
Tp = propagation delay
N = No. of stations in ring