Câu 73: H12-891: HCIE-Datacom

Which of the following statements regarding MPLS label encapsulation format are correct? (Choose three.)

1. A. The total length of one layer of MPLS label is 4 bytes. — đáp án hiện tại
2. B. The TTL field in an MPLS label has the similar meaning as that in an IP packet, and can prevent loops. — đáp án hiện tại
3. C. The S field in an MPLS label has 1 bit and is used to identify whether the label is the bottom-of-stack label. If the value is 1, the label is a penultimate-layer label. — đáp án hiện tại
4. D. For Ethernet and PPP packets, a label stack is located between the Layer 2 packet header and data. If a VLAN tag is available, the label stack is placed between Ethernet header and the VLAN tag.