Abstract

IP network
IP protocol is first level of Intenet network protocol and Addressing protocol of IP network. Packet address is fixed by IP protocol among this address define the principle. How the resource transmites the datas partly over network.
Routers have two independent functions: control and forwarding. Router maintain tables to choose the optimum route for packet forwarding. If the destination is reachable from a directly attached active link, the router will use that route. If a link fails or becomes congested, the routers communicate among themselves to update their tables. Routing protocols classified as interior and external protocols. Interior gateway protocols are optimized for operation within a single autonomous system. Border gateway protocol enable border routers located at the edge of the domains they serve to exchange routing information. BGP’s purpose is to manage the flow of transit traffic.
Multiprotocol label switching (MPLS) , an encapsulation protocol for tunneling through an IP network, is a service-enabling technology that is becoming the connerstone of VPN strategy for the major carriers.
MPLS, Virtual Private Network features enable multiple custumor sites interconnect across the service provider’s IP network with the characteristics of a private network.
The statistics that most carriers quote for their IP SLAs are specified within the network cores. Carriers typically quote percent availability, latency, and packet loss for city pairs.