방법 비교

	Multiprotocol Label Switching (MPLS)	차등 서비스 (DiffServ)	Open Shortest Path First (OSPF)	소프트웨어 정의 네트워킹 (SDN)
분야	통신공학	통신공학	통신공학	통신공학
계열	Process / pipeline	Process / pipeline	Process / pipeline	Process / pipeline
기원 연도	2001	1998	1998	2008
창시자	IETF MPLS Working Group	IETF DiffServ Working Group	John Moy	Nick McKeown et al.
유형	label-based forwarding paradigm	QoS architecture	link-state routing protocol	programmable network paradigm
원전	Rosen, E. C., Viswanathan, A., & Callon, R. (2001). Multiprotocol Label Switching Architecture. RFC 3031.	Blake, S., Black, D., Carlson, M., et al. (1998). An Architecture for Differentiated Services. RFC 2475.	Moy, J. T. (1998). OSPF Version 2. RFC 2328.	McKeown, N., Anderson, T., Balakrishnan, H., et al. (2008). OpenFlow: enabling innovation in campus networks. ACM SIGCOMM Computer Communication Review, 38(2), 69-74.
별칭	label switching, traffic engineering	quality of service, QoS architecture	link-state routing, intra-domain routing	network virtualization, programmable networks
관련	4	3	2	4
요약	Multiprotocol Label Switching (MPLS) is a forwarding paradigm that prepends a short label to packets, enabling routers to make forwarding decisions based on the label rather than IP destination address. Introduced by IETF (2001), MPLS was designed to enable traffic engineering, VPN creation, and fast rerouting in IP networks. While MPLS complexity is high, it remains foundational in service provider backbones for traffic engineering and Quality of Service (QoS) provisioning.	DiffServ is a QoS architecture providing scalable, class-based service differentiation in networks. Introduced by IETF (1998), DiffServ marks packets with a Differentiated Services Code Point (DSCP) in the IP header, enabling routers to apply per-hop-behaviors (PHBs) based on markings. Unlike IntServ (which reserves resources per-flow), DiffServ is stateless and scalable to Internet scale. DiffServ remains the primary QoS mechanism in ISP and enterprise networks.	OSPF is a link-state interior gateway protocol (IGP) for routing within an autonomous system. Introduced by John Moy in 1998, OSPF converges faster than distance-vector protocols and supports equal-cost multipath (ECMP). It remains widely deployed in enterprise and ISP networks for intra-domain routing, though IS-IS is increasingly preferred in large backbones.	Software-Defined Networking (SDN) is a network architecture paradigm that decouples the control plane (routing decisions) from the data plane (packet forwarding). Introduced by McKeown et al. (2008) with OpenFlow, SDN enables network programmability by centralizing control logic in software-based controllers that direct forwarding behavior of simple programmable switches. SDN has transformed network operations, enabling rapid service deployment, traffic engineering, and cloud integration. It is now foundational in data centers and service provider networks.