TCP建立后，哪个BGP对等体将首先发送打开消息？

在两个bgp对等体之间建立Tcp连接之后。哪个对等方将首先发送打开消息？是主动对等方（正在发起出站连接）还是被动对等方？（正在接受入站连接的对等端）。

还是它独立于这种主动的被动状态？任何对等方都可以基于调度发送第一个打开的消息吗？

在本地路由器发出打开消息之前收到打开消息时会发生什么？

有没有好的BGP Peer fsm图？RFC4271没有fsm图:(

哪个对等方将首先发送打开消息？

通常，打开插座的扬声器会发送第一个OPEN消息。但这实际上并不重要（请参考DelayOpen timer），因为BGP还提供了一种延迟OPEN消息的方法，以便对方可以首先发送：

    选项1：DelayOpen

    说明：DelayOpen可选会话属性允许
                 要配置为延迟发送的实现
                 特定时间段内的OPEN消息
                 （DelayOpenTime）。延迟允许远程BGP
                 对等时间发送第一条OPEN消息。

         值：TRUE或FALSE

如果两个扬声器都打开重复的TCP会话并在每个套接字上同时发送OPEN消息，则BGP标识符用于确定应关闭哪个套接字。参见RFC 4271第6.8节：

6.8. BGP Connection Collision Detection

If a pair of BGP speakers try to establish a BGP connection with each other 
simultaneously, then two parallel connections well be formed. If the source IP address 
used by one of these connections is the same as the destination IP address used by the 
other, and the destination IP address used by the first connection is the same as the 
source IP address used by the other, connection collision has occurred. In the event 
of connection collision, one of the connections MUST be closed.

Based on the value of the BGP Identifier, a convention is established for detecting 
which BGP connection is to be preserved when a collision occurs. The convention is to 
compare the BGP Identifiers of the peers involved in the collision and to retain only 
the connection initiated by the BGP speaker with the higher-valued BGP Identifier. 

有没有好的BGP Peer fsm图？

维基百科具有简化的BGP FSM。