For single-hop BFD (Bidirectional Forwarding Detection), the configuration must include the local and remote discriminators to uniquely identify the session endpoints. Additionally, enabling BFD globally is a prerequisite for initiating BFD sessions. Configuring multicast IP addresses is unnecessary for single-hop BFD, as it operates over direct links. Huawei's configuration guidelines specify these requirements to ensure effective deployment and operation of BFD.
Understanding BFD (Bidirectional Forwarding Detection):
* BFD is a protocol used to detect link faults quickly between two routers.
* Single-hop BFD operates on directly connected links and is commonly used for fast fault detection in routing protocols like OSPF and BGP.

Comprehensive and Detailed Step-by-Step Explanation:
Analysis of BGP Attributes:
Original Next Hop:The output shows that the original next hop of the route is 172.16.1.2. (A is correct).
Local Router ID:The local BGP router ID is 10.1.1.1, as displayed. (B is correct).
Local AS Number:The local AS number is 100, as displayed. (C is correct).
Incorrect Option:
Local_Pref:Although Local_Pref is an important attribute, this route is marked as invalid due to "IP unreachable" and thus cannot be preferentially selected.
References:
HCIA-Datacom Study Guide, Chapter: BGP Routing Attributes
Huawei BGP Routing Table Analysis

The provided BGP error display shows the error timestamp as 12:40:39 on March 22, 2010. The error message confirms a mismatch in the peer AS number, as indicated in the "Incorrect remote AS" error info.
This eliminates options related to other causes, and the timestamp in Option A is incorrect .

SSL VPN and Its Functionality:
SSL VPN (Secure Sockets Layer Virtual Private Network) provides secure remote access to a network using SSL/TLS protocols.
SSL VPN operates at theApplication Layerof the OSI model. It enables secure communication for applications like web browsers, email clients, and file sharing.
Unlike IPsec VPN, which operates at the Network Layer, SSL VPN focuses on application-specific encryption and authentication.
HCIP-Security Training Material (VPN Basics and SSL VPN Configuration).