350-501 Exam Dumps - Implementing and Operating Cisco Service Provider Network Core Technologies (350-501 SPCOR)

 In BGP, the weight attribute is the first criterion used to determine the best path. It is a Cisco-specific attribute and is not propagated in BGP updates. Weight is a numeric value, and the path with the highest weight is preferred. If weights are the same, BGP will then consider the local preference, AS path length, origin type, and other attributes in sequence.

References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) training material

 When implementing Nonstop Routing (NSR) High Availability on an MPLS Provider Edge (PE) router, it’s important to consider that NSR generally consumes more memory and CPU resources than Nonstop Forwarding (NSF) because it needs to maintain a stateful switchover capability. Additionally, NSR requires routing protocol extensions to ensure that the state information is correctly synchronized between the active and standby routers, allowing for seamless failover without session loss. This ensures continuous packet forwarding even during a switchover event.

 The issue described involves packets being dropped when sent from the application server to the access site. Since OSPF and BGP peerings are confirmed to be operational, the problem likely lies within the route advertisement. Allowing 172.16.20.1 in the BGP advertisement on R3 by adjusting the route-map will likely resolve the issue, ensuring that traffic destined for 172.16.20.1 is not being inadvertently filtered or blocked.

References:

• Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) course provides insights into configuring, verifying, troubleshooting, and optimizing Service Provider IP network infrastructures, which includes understanding and implementing BGP routing and route maps1.
• The official Cisco certification exam overview for SPCOR, which includes topics on BGP routing and route maps, can also serve as a reference

To ensure that a router advertises only networks with a prefix mask length less than or equal to 21 to its BGP neighbor, the correct configuration is Option A. This involves applying a prefix list that permits updates for networks with the specified prefix length. The prefix list acts as a filter for outgoing route advertisements in BGP, ensuring that only routes that match the criteria are advertised to the neighbor.

To inject a default route into the MP-BGP address family for a dedicated VRF, you would typically need to:

• Configure a static default route in the VRF using the ip route vrf 0.0.0.0 0.0.0.0  command.
• Redistribute the static route into BGP using the redistribute static command under the BGP VRF configuration.

 In OSPF, the election of the designated router (DR) and backup designated router (BDR) is based on the OSPF network type. The network types include:

• Broadcast: This is the default network type for Ethernet interfaces. In a broadcast network, OSPF elects a DR and BDR. All other routers become DROTHERs. To prevent the election of a DR/BDR, you can configure the interface as non-broadcast (NBMA) using the ip ospf network non-broadcast command.
• Point-to-Point: This network type is used for point-to-point links (e.g., serial links). There is no DR/BDR election in point-to-point networks.
• Point-to-Multipoint: This network type is used for point-to-multipoint links (e.g., Frame Relay). There is no DR/BDR election in point-to-multipoint networks.
• Point-to-Multipoint Non-Broadcast: Similar to point-to-multipoint, but explicitly configured as non-broadcast. There is no DR/BDR election in point-to-multipoint non-broadcast networks.
• Loopback: Loopback interfaces are always treated as point-to-point.
• Virtual-Link: Used for OSPF virtual links.
• Sham-Link: Used for OSPF sham links.
• Demand Circuit: Used for demand circuits (e.g., ISDN).
• Non-Broadcast: Explicitly configured as non-broadcast. There is no DR/BDR election in non-broadcast networks.

References:

• Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) v1.0

Wavelength-division multiplexing (WDM) is a technology which multiplexes a number of optical carrier signals onto a single fiber [1], using different wavelengths of light to carry different signals. This allows for a greater capacity for data transfer and enables the addition of new wavelengths in a fiber-optic network

R1

R2