协调器断网后，路由器为什么不能发现协调器断网

协调器断网后，路由器为什么不能发现协调器断网？

现在有一个路由器加入到了协调器网络上，把协调器断电，路由器的状态为什么不会改变？

协调器和路由器之间没有交互么，协调器断电，路由器会知道么？

希望ti工作人员答疑解惑一下。谢谢

协调器和路由器没有直接数据的交互，除非应用在应用层自己有添加。

如果协调器和路由器是邻居设备的，那么路由器会发现到协调器的链路断了，这个在邻居表中维护的。路由器和协调器每隔15s会发link status出来。

9.7 Asynchronous Links
An asynchronous link occurs when a node can receive packets from another node but it can’t send packets to that
node. Whenever this happens, this link is not a good link to route packets.
In ZigBee PRO, this problem is overcome by the use of the Network Link Status message. Every router in a ZigBee
PRO network sends a periodic Link Status message. This message is a one hop broadcast message that contains the
sending device’s neighbor list. The idea is this – if you receive your neighbor’s Link Status and you are either
missing from the neighbor list or your receive cost is too low (in the list), you can assume that the link between you
and this neighbor is an asynchronous link and you should not use it for routing.
To change the time between Link Status messages you can change the compile flag
NWK_LINK_STATUS_PERIOD, which is used to initialize _NIB.nwkLinkStatusPeriod. You can also
change _NIB.nwkLinkStatusPeriod directly. Remember that only PRO routers send the link status message
and that every router in the network must have the same Link Status time period.
_NIB.nwkLinkStatusPeriod contains the number of seconds between Link Status messages.
Another parameter that affects the Link Status message is _NIB.nwkRouterAgeLimit (defaulted to
NWK_ROUTE_AGE_LIMIT). This represents the number of Link Status periods that a router can remain in a
device’s neighbor list, without receiving a Link Status from that device, before it becomes aged out of the list. If we
haven’t received a Link Status message from a neighbor within (_NIB.nwkRouterAgeLimit *
_NIB.nwkLinkStatusPeriod), we will age the neighbor out and assume that this device is missing or that it’s
an asynchronous link and not use it.