This figure shows an SRv6 (Segment Routing over IPv6) packet.

1Comprehensive and Detailed In-Depth Explanation:1. Understanding SRv6 (Segment Routing over IPv6):SRv6 uses the IPv6 header along with an additional SRH (Segment Routing Header) to implement segment routing within an IPv6 network. The SRH contains:Segment List (SL): A list of IPv6 addresses (segments) to traverse.SL (Segments Left): An integer that indicates the number of segments yet to be visited.Active Segment: The next IPv6 address in the segment list, stored in the Destination Address field of the IPv6 header.2. Analyzing the Given Scenario:The segment list (SL) in the SRH header shows:FC04::400FC04::4FC03::3The segment list is processed in reverse order (from bottom to top).SL (Segments Left) indicates the index of the active segment in the list.The Destination Address in the IPv6 header is currently FC04::4, indicating that the active segment is the second element in the list.3. Determining the Value of SL:The indexing in the segment list starts from 0.Since FC04::4 is the second segment (from the bottom), the value of SL will be 1.This means that 1 segment is left to be processed after the current one (FC04::4).Once the packet reaches FC04::4, the SL value will decrement to 0, and the next segment (FC03::3) will be processed.4. Why the Answer is 1:The SL value decreases as segments are processed.As the current active segment is the second in the list (from the bottom), the SL value is 1.