Nokia 4A0-112 Dumps

Theadjacency databasecontains information about the state of the router’s adjacencies (i.e., the routers that it is directly connected to and has established a neighbor relationship with). It does not store information about all links in the domain; that information is stored in thelink-state database.

Router R1 is configured as L1/L2, meaning it is part of both Level 1 and Level 2 IS-IS routing areas. This means R1 will generate two types of LSPs:

Level 1 LSP (for the local area 49.0001) to advertise its local topology to other Level 1 routers.

Level 2 LSP (for the backbone area 49.0002) to advertise the global network topology to Level 2 routers.

R1 also has two broadcast interfaces, and as the Designated Intermediate System (DIS) on these interfaces, it will generate an LSP for each interface (one per broadcast link).

This results in three total LSPs:

A Level 1 LSP for the local area (49.0001).

A Level 2 LSP for the backbone area (49.0002).

An LSP for each of the two broadcast interfaces, which may include interface-related topology information.

Dividing a domain into areas typically does not reduce the number of routers needed to handle traffic. It is more focused on improving scalability, reducing the size of routing tables, and limiting the scope of SPF calculations, but it doesn't inherently reduce the number of routers required.

In IPv6, the Neighbor Discovery Protocol (NDP) replaces the Address Resolution Protocol (ARP) used in IPv4. NDP is responsible for several functions, including resolving IP addresses to MAC addresses (similar to ARP), detecting duplicate IP addresses, and discovering other devices on the network.

When a link-state update reaches its maximum age, it isremovedfrom the router’s link-state database, not flooded to its neighbors. This prevents outdated information from continuing to affect the routing decisions. The router does not flood the aged update; instead, it will typically request a new link-state advertisement from the original source router if the information is still needed.

From R1 to R7: The path will be R1 → R2 → R4 → R6 → R7 because this path has the least cumulative metric of 10 + 10 + 10 + 10 = 40.

From R7 to R1: The reverse path will follow R7 → R6 → R4 → R2 → R1 because it is the shortest return path with the same metrics.

Router R1 is the one that performs the summarization of the two subnets (20.20.1.0/24 and 20.20.2.0/24) into the summarized route 20.20.0.0/16. However, R1 itself will not see any change in its routing table because it is directly connected to both subnets and already knows about them.

Router R2, which is in Area 49.0002, will benefit from this summarization because it previously had separate routes for both 20.20.1.0/24 and 20.20.2.0/24. After the summarization, R2 will only need to maintain a single route to 20.20.0.0/16, reducing the size of its routing table.

Router R4 does not directly benefit from the summarization because it is only connected to the Level 1 network and has no need for the summarized routes from R1. Thus, the summarization does not affect R4's routing table.

The output shows two levels of IS-IS databases: Level 1 (L1) and Level 2 (L2). This indicates that the domain is multi-area, as L1 routers are confined to a single area, while L2 routers can route between different areas. The presence of Level 1/Level 2 (L1/L2) routers also suggests that the domain spans multiple areas.

The LSP (Link-State PDU) entries show L1/L2 ATT attributes, which typically indicate that these routers are capable of routing both within their own area (Level 1) and across areas (Level 2), suggesting a multi-area design.

The IS-IS domain likely includes broadcast interfaces, as indicated by the "ATT" attribute (typically referring to the type of interface) and common IS-IS configuration practices on broadcast networks like Ethernet.

Typically, interfaces on a Nokia 7750 SR router are not configured in pairs on the same subnet for redundancy. Instead, redundancy is achieved through mechanisms like Virtual Router Redundancy Protocol (VRRP) or other high availability protocols, not by simply using interfaces in pairs on the same subnet.

From the output, we can see that theusagecolumn indicates whether a router is operating as an L1 or L2 router:

RoutersR1andR2have a usage ofL2, meaning they are L2 routers.

RoutersR3andR4have a usage ofL1, meaning they are L1 routers.

TheL1/L2designations refer to whether the routers participate in both Level 1 and Level 2 of IS-IS:

L1 routersonly communicate within their own area.

L2 routerscommunicate between areas.

In this case,R1andR2are L2 routers, andR3andR4are L1 routers.

In IS-IS, routers are actually associated withinterfacesrather than the entire router being associated with a single area. A router can have interfaces in multiple areas, and it is the interface's configuration that determines which area it belongs to.

The static route configured on router R1 uses an indirect next-hop, which is10.10.10.3 (R3). While the echo request from R1 reaches the server through the IGP, the problem lies in the return path for the echo response.

The route10.4.100.0/24is reachable throughR3, but there is no reciprocal route inR3's routing table that allows the response to flow back towardsR1. This results in a failure to return the echo response to R1, causing the ping to fail.