Huawei AR1200 Series Configuration Manual - Mpls page 131

Huawei AR1200 Series Enterprise Routers
Configuration Guide - MPLS
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PeerID
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2.2.2.9:0
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TOTAL: 1 session(s) Found.
Step 4 Configure LDP GTSM.
# On LSRA, configure the range of valid TTL values carried in LDP packets received from
LSRB to be from 253 to 255.
<LSRA> system-view
[LSRA] mpls ldp
[LSRA-mpls-ldp] gtsm peer 2.2.2.9 valid-ttl-hops 3
# On LSRB, configure the range of valid TTL values carried in the LDP packets received from
LSRA to be from 252 to 255, and the range of valid TTL values carried in LDP packets received
from LSRC to be from 251 to 255.
<LSRB> system-view
[LSRB] mpls ldp
[LSRB-mpls-ldp] gtsm peer 1.1.1.9 valid-ttl-hops 4
[LSRB-mpls-ldp] gtsm peer 3.3.3.9 valid-ttl-hops 5
# On LSRC, configure the range of valid TTL values carried in LDP packets received from
LSRB to be from 250 to 255.
<LSRC> system-view
[LSRC] mpls ldp
[LSRC-mpls-ldp] gtsm peer 2.2.2.9 valid-ttl-hops 6
Then, if the host PC simulates sending LDP packets from LSRA to attack LSRB, LSRB discards
the packets directly because the TTL values carried in the LDP packets are not within the range
of 252 to 255. In the GTSM statistics on LSRB, the number of discarded packets increases.
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Configuration Files
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Issue 01 (2011-12-30)
Status
Operational DU
Configuration file of LSRA
#
sysname LSRA
#
mpls lsr-id 1.1.1.9
mpls
#
mpls ldp
gtsm peer 2.2.2.9 valid-ttl-hops 3
#
interface GigabitEthernet1/0/0
ip address 10.1.1.1 255.255.255.252
mpls
mpls ldp
#
interface LoopBack1
ip address 1.1.1.9 255.255.255.255
#
ospf 1
area 0.0.0.0
network 1.1.1.9 0.0.0.0
network 10.1.1.0 0.0.0.3
#
return
Configuration file of LSRB
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