discovery transport-address interface versus ldp neighbor

Hi
If we are using <mpls ldp discovery transport-address interface> the
LDP TCP sessions are going to source
from the interface address and not the Router-ID.
Command reference guide for <mpls ldp neighbor a.b.c.d password> says
that Router-ID should be used
as an argument.

However some test I did shows that in this combination the later
command work perfectly fine using as
argument either the router id, either the destination IP address of
the LDP TCP session
(have to use same process on both router:either use router ids on both
, either use destinations TCP address on both)

Some workbooks are using the TCP destination as the argument for the
mpld ldp neighbor
password command especially in the CSC scenario but what I described
earlier applies for csc also.

Now if the task asks to use both commands what should we use as an
argument for the password command ?
I guess is something that needs to be clarified with the proctor.

Here is an example:
R4--R9

Using the TCP destination for the password
R9(config)#do sri test
mpls ldp neighbor 200.4.9.4 password test
R9(config)#do sh mpls ldp nei 200.200.200.4
    Peer LDP Ident: 200.200.200.4:0; Local LDP Ident 200.200.200.9:0
        TCP connection: 200.4.9.4.646 - 200.4.9.9.11067
        State: Oper; Msgs sent/rcvd: 23/24; Downstream
        Up time: 00:10:22
        LDP discovery sources:
          Serial4/0.904, Src IP addr: 200.4.9.4
        Addresses bound to peer LDP Ident:
          200.4.6.4 200.200.200.4 200.200.200.204 100.200.45.4
          200.4.6.134 200.4.9.4
R9(config)#
R4(config)#do sri test
mpls ldp neighbor 200.200.200.9 password test
R4(config)#do sh mpls ldp nei 200.200.200.9
    Peer LDP Ident: 200.200.200.9:0; Local LDP Ident 200.200.200.4:0
        TCP connection: 200.4.9.9.11067 - 200.4.9.4.646
        State: Oper; Msgs sent/rcvd: 25/23; Downstream
        Up time: 00:11:06
        LDP discovery sources:
          Serial4/0.409, Src IP addr: 200.4.9.9
        Addresses bound to peer LDP Ident:
          200.4.9.9 200.6.9.9 200.200.200.9 200.200.200.209
R4(config)#

Using the router id for password:
R9(config)#do sri test
mpls ldp neighbor 200.4.9.4 password test
R9(config)#do sh mpls ldp nei 200.200.200.4
    Peer LDP Ident: 200.200.200.4:0; Local LDP Ident 200.200.200.9:0
        TCP connection: 200.4.9.4.646 - 200.4.9.9.11067
        State: Oper; Msgs sent/rcvd: 23/24; Downstream
        Up time: 00:10:22
        LDP discovery sources:
          Serial4/0.904, Src IP addr: 200.4.9.4
        Addresses bound to peer LDP Ident:
          200.4.6.4 200.200.200.4 200.200.200.204 100.200.45.4
          200.4.6.134 200.4.9.4
R9(config)#

R4(config)#do sri test
mpls ldp neighbor 200.200.200.9 password test
R4(config)#do sh mpls ldp nei 200.200.200.9
    Peer LDP Ident: 200.200.200.9:0; Local LDP Ident 200.200.200.4:0
        TCP connection: 200.4.9.9.11067 - 200.4.9.4.646
        State: Oper; Msgs sent/rcvd: 25/23; Downstream
        Up time: 00:11:06
        LDP discovery sources:
          Serial4/0.409, Src IP addr: 200.4.9.9
        Addresses bound to peer LDP Ident:
          200.4.9.9 200.6.9.9 200.200.200.9 200.200.200.209
R4(config)#
R4(config)#

-- 
br,
Ovidiu
#18857 RS
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