Hi Tony,

For the case you described below, in order to add one or a limited number of 
links to the flooding topology temporarily, a new bit, called Flooding 
Negotiation bit (FN bit for short), should be defined and used. In OSPF, the FN 
bit is defined in Extended Options and Flag (EOF) TLV in OSPF Hello. In IS-IS, 
the FN bit is defined in the new TLV used for FR bit.

When a node N (with 1000 interfaces/links for example) reboots, , each (node X) 
of the nodes connected to node N will establish an adjacency with node N. 
During the process of the adjacency establishment between node X and node N, 
node X sends a FN-bit set to one in its Hello to node N, node N selects one 
link/node (or a limited number of links) for temporarily flooding and sends 
only to this selected node a FN-bit set to one in its Hello. Node N adds the 
selected link/node to the FT temporarily after receiving the FT bit set to one 
from the selected node. After receiving the FN bit set to one from node N, the 
selected node adds the link (connected to node N) to the FT temporarily.
In other words, a node Y connected to node N adds the link to node N to the FT 
temporarily after it sends and receives the FT bit set to one to/from node N; 
node N adds a selected link to the FT temporarily after it receives and sends 
the FT bit set to one from/to node Y.

Best Regards,
Huaimo

==== A case from Tony on 3/6 ====
If the node that rebooted has 1000 interfaces, which interfaces should be 
temporarily added?  Adding all of them is likely to trigger a cascade failure.  
The TLV allows us to signal which ones should be enabled.
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