isis confusions

[weifeng.l]

1.Why does not cisco's isis add authentication CLV in SNPDUs,even text authentication has been enable on both area and domain level?

2.

RouterA-------------------------------RouterB

L1L2 L1L2

Enable isis on RouterA and RouterB,config both Routers in same area.They will establish L1 and L2 adj.Now change RouterB as level-2 only,but "show clns is-nei" on RouterA indicate that RouterB is still L1 and L2 adj.Why can not L1 adj be broken down?

3.I have config max-area 200 on cisco router,But I find that all L2 LAN-HELLOs have max-area field 200,but all L2 LSPs have max-area field 0,why? If A and B want to establish

L2 adj,but max-area is not the same,will this adj be OK?

[vkapoor5]

It is really suprising to see L1L2 adjacency for your question no.2 even after changing RouterB as L2-only. Check if this is a known issue with the hardware or software that you are using. You can also use 'debug isis adj-packets' to see what happends during hello exchange.