QoS and differentiated services in a multiservice network environment

Service differentiation is a prerequisite for satisfying the variety and ra nge of quality of service (QoS) demands placed on an integrated services ne twork. This paper explores different technology options for an integrated s ervices infrastructure and analyzes them for their ability to satisfy multi service requirements such as those needed for virtual private network (VPN) intranet applications. The analysis draws on concepts from Internet protoc ol (IP) and asynchronous transfer mode (ATM) network; their interworking, a s in the multiprotocol label switching (MPLS) and multiprotocol over ATM (M POA) approaches; and switching, routing, and signaling. A QoS spectrum rela ting the many traffic control schemes to the different classes of service i s a contribution of this paper. Evolution paths from an existing infrastruc ture of IP routers offering best-effort service to an infrastructure offeri ng differentiated and guaranteed services are identified. The paper include s a proposal for supporting differentiated and guaranteed services in the M POA framework. In this paper, all traffic offered to a network domain is as sumed IP.