4A0-103 Nokia Multi Protocol Label Switching Questions and Answers

Enable the Idp-over-rsvp feature on all PEs and ABRs along the LSP tunnel.

Configure Link-LDP sessions between each PE-ABR and ABR-ABR pair.

Configure RSVP-TE LSPs in each area between each PE-ABR and ABR-ABR pair.

Configure T-LDP sessions with the tunneling option.

Conservative label retention

Liberal label retention

Downstream on demand

Downstream unsolicited

A new LDP session is established on R1-R3-R6 as soon as the FIB is updated.

The LDP session remains unchanged until the existing path R1-R2-R4-R6 goes down.

A new LDP session is established on R1-R3-R6 as soon as router R1 receives a new label for router R6.

The LDP session remains unchanged until router R3 stops advertising the maximum metric for the link to router R6.

MPLS Echo Request packets are sent within the RSVP-TE tunnel that is signaled for "lsp-toR2".

MPLS Echo Request packets are sent within the LDP tunnel that is signaled for Mlsp-toR2".

MPLS Echo Request packets are IP-routed to the destination address of "lsp-toR2".

MPLS Echo Request packets are sent to the destination address of "lsp-toR2" over TCP.

configure router mpls retry-timer 30

configure router mpls resignal-timer 30

configure router mpls retry-attempts 30

configure router mpls global-revertive 30

The router performs a unidirectional LSP test.

The router collects hop information along the tunnel's path.

The router uses MPLS Echo Request packets that are IP-routed,

The MPLS TTL values are incremented at each request.

LSPs must always terminate on a system ID.

MPLS and RSVP must be enabled on all routers.

Interfaces must be individually created in RSVP.

Path definitions must include at least one hop entry.

Admin groups can be configured using the command "configure>router>mpls>admin-group".

CSPF uses the information defined by admin groups when paths are computed for constraint-based LSPs.

By default, interfaces for which MPLS has been enabled are in the default admin group.

A LSP can make use of admin groups for constraint-based path calculations by including or excluding the admin group

By defining new LSAs for the IS-IS protocol.

By utilizing the OSPF opaque LSAs to maintain interoperability with OSPF routing domains

By defining new TE extension TLVs to the IS-IS protocol.

By enabling CSPF algorithm extensions that allow link state TE to be implemented.

The LSP is in the administrative down state.

The router's router ID overlaps another.

The router's interfaces do not have LDP running.

The router's system interface requires an IP address

A router will never receive a packet containing this label value.

Request a new label from the peer that provided this label.

Pop the label.

PUSH an additional label onto the label stack.

Signal a new label to the peer that sent the packet.

PE, P

LER,LSR

LSR,LER

iLER, eLER

eLER, iLER

P, PE

The router has new entries added for the given FEC in its LIB.

The router has new entries added for the given FEC in its FIB.

The router generates a single label for the given FEC and advertises it to all its peers,

The router has multiple LSP tunnels for the given FEC.

Local FECs not included in the 192.168.1.0/24 address space and the system IP FEC.

Only the system IP FEC appears in the LIB.

Any local FECs, except those with a 24-bit mask.

Local FECs in the 192.168.1.0/24 address space.

RSVP LSPs must exist between each PE-ABR pair, or ABR-ABR pair in each area.

When LDP-over-RSVP is active, the LDP prefixes are resolved to a physical egress interface.

Targeted sessions must exist between all routers along the tunnel path.

Link LDP sessions must exist between each ABR-ABR pair in each area.

A mechanism that implements opaque LSAs.

A mechanism that computes routes based on specified requirements.

A mechanism that ensures the IGP best route is used.

A mechanism that enables LDP signaling to use a route other than the IGP best route.

Router R1 will switch traffic to the secondary path immediately.

Router R1 will discard traffic until a new IGP route to router R6 is re-calculated.

Router R1 will discard traffic because the secondary path isnot a fully strict path.

Router R1 will signal the secondary path and switch traffic to it.

The LSP can use protection tunnels used by other LSPs.

The LSP can use facility and one-to-one FRR simultaneously.

The LSP is limited to link protection.

A detour protection tunnel is created for this LSP.

RSVP-TE supports Connection Admission Control (CAC).

RSVP-TE enables simplified configuration of LSPs.

RSVP-TE supports path calculations that do not use IGP cost.

RSVP-TE provides support for traffic protection features.

Router R1 updates its FIB after a new SPF calculation.

Router R1 switches to a secondary path.

Router R4 switches to a FRR path.

Router R4 switches to a standby secondary path.

1

2

3

4

The router will switch to Path-2 because it is the first secondary path configured in the list.

The router will not switch to Path-2 because the current path has the longest uptime.

The router will switch to Path-2 because it is a more preferred path.

The router will not switch to Path-2 because the router will not revert to another secondary path.

The LSP will switch to R1-R3-R5-R6 after the resignal timer expires.

The old primary path and its detours are torn down after the new primary path is established.

CSPF must be enabled to find a more optimal path.

The traffic is switched to R1-R3-R5-R6 in an MBB fashion.

The time router R4 takes to send a PATH Error message toward the head-end router.

The time router R4 takes to detect RSVP Hello message timeout from router R6.

The time router R4 takes to send a RESV Error message to the head-end router.

The time router R1 takes to signal an alternate path through router R3.

CSPF must be enabled at head-end on fast reroute protected loose path LSPs

Fast reroute must first be enabled on the downstream routers.

CSPF must be enabled on all downstream loose hop routers.

Global revertive path optimization must be enabled so the path will be re-optimized around a failed node.

Targeted sessions must exist between all routers in the tunnel's path.

Each LDP interface must be configured to support LDP tunneling.

LDP prefixes resolve to an RSVP LSP, rather than to a physical egress interface.

RSVP LSPs must exist between each PE-ABR pair, or ABR-ABR pair in each area.

CSPF chooses a link that is a member of both administrative groups

CSPF chooses only those links that are NOT members of the green admin group

CSPF prunes the green links and uses these links for the secondary path

CSPF signals the LSP path over the green links only, and prunes all other links

A mechanism that implements opaque LSAs.

A mechanism that computes routes based on defined user requirements.

A mechanism that allows the IGP shortest path to be used.

A mechanism that allows RSVP or LDP signaling to use a route other than the IGP best route to establish a LSP.

show router mpls Isp "LSP 1" originate

show router mpls Isp "LSP 1" path detail

show router rsvp session originate

show router rsvp session "LSP 1"

Router R1

Router R2

Router R3

Router R4

Router R5

Fixed filter

Shared explicit

Standby explicit LSP

Preemptive filter

Link capacity filter

The path message's IP header options field sets the router alert option.

The IP header source address is the sender's egress interface address.

The IP header destination address is the next-hop interface address.

The IP header HOP object reflects the upstream router's egress interface address.

Configure the T-LDP peers for tunneling.

Configure tunneled T-LDP sessions between PE routers.

Enable Idp-over-rsvp in the IGP configuration on the PEs and ABRs

Enable LSP stitching on the RSVP LSPs

from prefix-list direct

match local

from protocol direct

match protocol direct

from protocol local