Which transport-layer protocol is commonly described as message-oriented and supports multi-streaming and multi-homing?

• A. TCP
• B. UDP
• C. SCTP
• D. RTP

Answer: (C)

SCTP is described as message-oriented and supports multi-streaming and multi-homing. Its message-oriented nature means data is delivered in discrete messages with boundaries preserved, unlike a byte-stream like TCP where data can be fragmented or reassembled in arbitrary ways. This makes SCTP well suited for applications that rely on distinct messages rather than a continuous stream.

Multi-streaming within a single SCTP association allows multiple independent logical streams to coexist. If one stream pauses, the others can continue, reducing head-of-line blocking and improving efficiency for multiplexed data.

Multi-homing lets an endpoint have multiple IP addresses, providing path redundancy and quicker failover if one network path becomes unavailable. These features together distinguish SCTP from other transport protocols.

For contrast: TCP is a reliable byte-stream protocol without inherent message boundaries, multi-streaming, or multi-homing guarantees. UDP provides datagrams without delivery guarantees. RTP is designed for real-time media and sits atop UDP, focusing on timing rather than preserving message boundaries or multi-path capabilities.