Configuration Analysis:
OnR2, the following configuration has been applied:
acl 200
rule deny source 10.1.0.0 0.0.3.0
rule permit
#
ospf 1
filter-policy 2000 import
This configuration usesACL 200to filter routes during import into the OSPF routing table on R2.
Rule deny source 10.1.0.0 0.0.3.0:Blocks routes in the range10.1.0.0/24 to 10.1.3.0/24(inclusive).
Rule permit:Allows all other routes to be imported.
Impact of ACL 200 on Route Import:
10.1.0.0/24 to 10.1.3.0/24:These subnets are explicitly denied by ACL 200 and will not appear in R2's routing table.
10.1.4.0/24 and beyond:These subnets are permitted by therule permitstatement and will be imported into R2's routing table.
Routing Table Entries on R2:
Option A (10.1.4.0/24):Exists in R2's routing table because it is permitted.
Option B (10.1.3.0/24):Does not exist because it is denied by ACL 200.
Option C (10.1.2.0/24):Does not exist because it is denied by ACL 200.
Option D (10.1.1.0/24):Does not exist because it is denied by ACL 200.
A (10.1.4.0/24)
References:
HCIA-Datacom Study Guide, Chapter: OSPF Route Filtering
Huawei ACL Configuration for Route Policies

greater-equal-value: 26 , less-equal-value: 32
Explanation:
1. Understanding Prefix List Configuration:
The command ip ip-prefix huawei index 10 permit 10.1.1.0 24 greater-equal 26 defines a prefix filter:
* The base prefix is 10.1.1.0/24.
* The greater-equal 26 condition specifies that the mask length of matching prefixes must be at least 26 bits.
* If the less-equal parameter is not explicitly defined, the default value is 32, meaning the longest possible mask length for IPv4.
2. Explanation of Values:
* greater-equal-value: Specifies the minimum mask length. In this case, the value is 26.
* less-equal-value: Specifies the maximum mask length. Since it is not explicitly configured, the default value is 32.
3. Summary:
* greater-equal-value = 26
* less-equal-value = 32

Comprehensive and Detailed in-depth Step-by-Step Explanation:
BGP confederations are used to reduce the complexity of IBGP full-mesh connections within a large AS by dividing the AS into multiple sub-ASs (called "member ASs") while still appearing as a single AS to external ASs. Below is an analysis of each option:
A: The ASs outside a confederation still consider the confederation as one AS:
This istrue.Externally, the entire confederation is seen as a single AS, identified by the main AS number.
B: After a confederation is configured, the original IBGP attributes can be retained:
This istrue.The configuration of a confederation does not affect the IBGP attributes exchanged between routers.
C: After a confederation is configured, the original AS number is used as the confederation ID of each router:
This istrue.The main AS number is used as the Confederation Identifier for all member ASs in the confederation.
D: A confederation divides an AS into several sub-ASs, and EBGP full-mesh connections are established in each sub-AS:
This isfalse.Within each sub-AS of a confederation,IBGP connectionsare still used (not EBGP).
Confederations are designed to reduce the number of IBGP full-mesh connections required within a large AS by creating smaller, manageable sub-ASs.
Therefore, the correct answer isD.
References:
Huawei HCIA-Datacom Study Guide, Chapter on "BGP Confederations".
RFC 5065 - Autonomous System Confederations for BGP.

BGP Next_Hop Attribute
* Unlike IGP, the Next_Hop attribute in BGP does not necessarily have to be the IP address of a peer interface. For example, in multi-hop BGP configurations, the Next_Hop can point to a different router or interface within the network.
HCIP-Datacom-Core Reference
* Details of the Next_Hop attribute and its behavior are outlined in BGP path selection principles.

Comprehensive and Detailed Step-by-Step Explanation:
1. Overview of BFD Optimization:
* BFD (Bidirectional Forwarding Detection) is a protocol that provides rapid detection of link failures.
* Optimizing BFD involves adjusting parameters to balance between detection speed and network stability.
2. Analysis of Each Statement:
Option A: After a high priority is configured for BFD packets, BFD packets are preferentially forwarded.
* Correct (True Statement).
* High priority ensures that BFD packets are not delayed or dropped under congestion, improving detection accuracy.
Option B: To quickly learn about the network status and performance requirements, you can set the interval for sending BFD packets to the minimum value.
* Incorrect (False Statement).
* Setting the interval to the minimum value can lead to excessive BFD session flapping, which may overload the network or cause instability. The interval should be configured based on network requirements and conditions, rather than set to the minimum.
Option C: On a live network, some devices switch traffic only when a BFD session changes to the Up state... configure a delay to compensate for the time difference.
* Correct (True Statement).
* This is a valid optimization to avoid issues caused by timing mismatches between BFD and routing protocols.
Option D: If a BFD session flaps, master/backup switchovers are frequently performed... set the WTR time.
* Correct (True Statement).
* The WTR (Wait to Restore) timer helps stabilize BFD by delaying session recovery after a flap, reducing the risk of frequent switchovers.
3. Summary:
* The false statement is B, as setting the BFD packet interval to the minimum can destabilize the network.