VPRN Service Configuration Commands
Page 1080 7750 SR OS Services Guide
ttl-security
Syntax ttl-security min-ttl-value
no ttl-security 
Context config>service>vprn>bgp>group
config>service>vprn>bgp>group>neighbor
Description Configure TTL security parameters for incoming packets.
Parameters min-ttl-value — Specify the minimum TTL value for an incoming BGP packet.
Values 1 — 255
Default 1