Zte ZXR10 GER User Manual page 299

Last two bytes indicate the internal label space ID of the LSR.
For the label space per platform, the last two bytes are
always "0".
Rules for Rules for selecting the router ID of an LDP on ZXR10 GER
selecting Routers are as follows:
router ID
If mpls ldp router-id command is used to designate the
address of an interface as the router ID, and also the
interface has an IP address and is in UP status, the interface
will serve as the router ID.
If there are loopback interfaces configured with an IP
address, maximum IP address among the IP addresses of all
the loopback interfaces will serve as the router ID.
Maximum
configured with IP addresses in UP status is selected as the
router ID.
LDP hello An LSR sends LDP hello messages periodically, indicating that it
messages hopes to advertise label binding to find LDP peers. A Hello
message contains the LDP ID of the label space that the LSR
wants to advertise. The LDP uses UDP as a transmission protocol
to send the Hello message, with the port ID of 646.
When an LSR receives a Hello message from another LSR, it will
"think" that it has found an LSR and its special label space. If
two LSRs find each other, they will start to set up an LDP session.
LDP defines two types of discovery mechanisms. At present,
ZXR10 GER router supports basic discovery mechanism, used to
discover directly-connected peers. Hello message in basic
discovery mechanism is sent on all interfaces configured with
LDP, with multicast addresses of "all routers on the subnet" as
the destination addresses.
Procedure The procedure for setting up an LDP session between two LSRs
is as follows.
1. Open a TCP connection used for label distribution.
On ZXR10 GER, by default, router ID of LDP serves as the
transport address of the TCP connection. Alternatively, in
interface
transport-address command can be used to designate an
IP address or source IP address for sending Hello messages
can serve as the transport address of the TCP connection.
NOTE:
route to TCP transport address of another LSR.
2. Negotiate LDP session parameters
Parameters to be negotiated are label distribution mode
(independent
label distribution on demand) and other parameters.
After the LDP session is set up, the LDP can start label
distribution.
one among
configuration
To set up a TCP connection, an LSR should have a
downstream
Confidential and Proprietary Information of ZTE CORPORATION
Chapter 19 MPLS Configuration
the IP addresses
mode, mpls ldp
label distribution/downstream
of interfaces
discovery
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