VPRN inter-AS option C and ASBR/ABR/data path RR for BGP IPv4 label route

      ASBR1     ASBR2
            -------- D ------- E -------- 
           |                             |
           |                             | 
A -------- C                             F -------- B 
CE1       PE1                           PE2        CE2
           |                             |
           |                             |
            -------- G ------- H --------
                   ASBR3     ASBR4

# 12.0R4 default behavior

*A:Dut-B# traceroute 16.1.1.1 source 26.1.1.2 detail no-dns 
wait 100 traceroute to 16.1.1.1 from 26.1.1.2, 30 hops max, 40 byte packets
  1   1  26.1.1.1  1.90 ms
  1   2  26.1.1.1  1.81 ms
  1   3  26.1.1.1  2.01 ms
  2   1  16.1.1.1  6.11 ms
  2   2  16.1.1.1  8.35 ms
  2   3  16.1.1.1  5.33 ms

*A:Dut-C# traceroute router 600 26.1.1.2 source 16.1.1.1 detail no-dns 
wait 100 traceroute to 26.1.1.2 from 16.1.1.1, 30 hops max, 40 byte packets
  1   1  26.1.1.1  5.03 ms
  1   2  26.1.1.1  4.60 ms
  1   3  26.1.1.1  4.60 ms
  2   1  26.1.1.2  6.54 ms
  2   2  26.1.1.2  5.99 ms
  2   3  26.1.1.2  5.74 ms


# With ttl-propagate vprn-transit all and icmp-tunneling

*A:Dut-B# traceroute 16.1.1.1 source 26.1.1.2 detail no-dns 
wait 100 traceroute to 16.1.1.1 from 26.1.1.2, 30 hops max, 40 byte packets
  1   1  26.1.1.1  2.05 ms
  1   2  26.1.1.1  1.87 ms
  1   3  26.1.1.1  1.85 ms
  2   1  10.10.4.4  8.42 ms
         returned MPLS Label Stack Object
             entry  1:  MPLS Label =  262143, Exp = 0, TTL =   1, S = 0
             entry  2:  MPLS Label =  262137, Exp = 0, TTL =   1, S = 0
             entry  3:  MPLS Label =  262142, Exp = 0, TTL =   1, S = 1
  2   2  10.10.4.4  5.85 ms
         returned MPLS Label Stack Object
             entry  1:  MPLS Label =  262143, Exp = 0, TTL =   1, S = 0
             entry  2:  MPLS Label =  262137, Exp = 0, TTL =   1, S = 0
             entry  3:  MPLS Label =  262142, Exp = 0, TTL =   1, S = 1
  2   3  10.10.4.4  5.75 ms
         returned MPLS Label Stack Object
             entry  1:  MPLS Label =  262143, Exp = 0, TTL =   1, S = 0
             entry  2:  MPLS Label =  262137, Exp = 0, TTL =   1, S = 0
             entry  3:  MPLS Label =  262142, Exp = 0, TTL =   1, S = 1
  3   1  10.10.1.2  5.54 ms
         returned MPLS Label Stack Object
             entry  1:  MPLS Label =  262137, Exp = 0, TTL =   1, S = 0
             entry  2:  MPLS Label =  262142, Exp = 0, TTL =   2, S = 1
  3   2  10.10.1.2  7.89 ms
         returned MPLS Label Stack Object
             entry  1:  MPLS Label =  262137, Exp = 0, TTL =   1, S = 0
             entry  2:  MPLS Label =  262142, Exp = 0, TTL =   2, S = 1
  3   3  10.10.1.2  5.56 ms
         returned MPLS Label Stack Object
             entry  1:  MPLS Label =  262137, Exp = 0, TTL =   1, S = 0
             entry  2:  MPLS Label =  262142, Exp = 0, TTL =   2, S = 1
  4   1  16.1.1.1  9.50 ms
  4   2  16.1.1.1  5.91 ms
  4   3  16.1.1.1  5.85 ms


# With ttl-propagate vprn-local all
*A:Dut-C# traceroute router 600 26.1.1.2 source 16.1.1.1 detail no-dns 
wait 100 traceroute to 26.1.1.2 from 16.1.1.1, 30 hops max, 40 byte packets
  1   1  10.10.4.2  4.78 ms
         returned MPLS Label Stack Object
             entry  1:  MPLS Label =  262143, Exp = 7, TTL =   1, S = 0
             entry  2:  MPLS Label =  262136, Exp = 7, TTL =   1, S = 0
             entry  3:  MPLS Label =  262142, Exp = 7, TTL =   1, S = 1
  1   2  10.10.4.2  4.56 ms
         returned MPLS Label Stack Object
             entry  1:  MPLS Label =  262143, Exp = 7, TTL =   1, S = 0
             entry  2:  MPLS Label =  262136, Exp = 7, TTL =   1, S = 0
             entry  3:  MPLS Label =  262142, Exp = 7, TTL =   1, S = 1
  1   3  10.10.4.2  4.59 ms
         returned MPLS Label Stack Object
             entry  1:  MPLS Label =  262143, Exp = 7, TTL =   1, S = 0
             entry  2:  MPLS Label =  262136, Exp = 7, TTL =   1, S = 0
             entry  3:  MPLS Label =  262142, Exp = 7, TTL =   1, S = 1
  2   1  10.10.6.4  4.55 ms
         returned MPLS Label Stack Object
             entry  1:  MPLS Label =  262138, Exp = 7, TTL =   1, S = 0
             entry  2:  MPLS Label =  262142, Exp = 7, TTL =   2, S = 1
  2   2  10.10.6.4  4.47 ms
         returned MPLS Label Stack Object
             entry  1:  MPLS Label =  262138, Exp = 7, TTL =   1, S = 0
             entry  2:  MPLS Label =  262142, Exp = 7, TTL =   2, S = 1
  2   3  10.10.6.4  4.20 ms
         returned MPLS Label Stack Object
             entry  1:  MPLS Label =  262138, Exp = 7, TTL =   1, S = 0
             entry  2:  MPLS Label =  262142, Exp = 7, TTL =   2, S = 1
  3   1  26.1.1.1  4.62 ms
  3   2  26.1.1.1  4.41 ms
  3   3  26.1.1.1  4.64 ms
  4   1  26.1.1.2  5.74 ms
  4   2  26.1.1.2  6.22 ms
  4   3  26.1.1.2  5.77 ms