초록 ▼

A large flat IP network is created in a switched layer-2 network by adjusting the subnet masks of hosts such that these hosts can communicate directly with other hosts without the use of an intermediate router. The layer-2 switches are configured with user-selected IP subnets and monitor and analyze

A large flat IP network is created in a switched layer-2 network by adjusting the subnet masks of hosts such that these hosts can communicate directly with other hosts without the use of an intermediate router. The layer-2 switches are configured with user-selected IP subnets and monitor and analyze multicast packets to learn the mapping between IP subnets and switch ports. The layer-2 switches selectively forward the mulitcast packets based on the learned mappings between IP subnets and ports. After the destination host responds to the forwarded multicast, a direct connection is established between the source and destination hosts using the media access control addresses of both hosts.

대표청구항 ▼

[ What is claimed is:] [1.]1. A switch for providing a data link layer switching function between distinct subnetworks of a data communications system having a plurality of interconnected subnetworks for enabling end stations on the distinct subnetworks to communicate directly without the use of rou

[ What is claimed is:] [1.]1. A switch for providing a data link layer switching function between distinct subnetworks of a data communications system having a plurality of interconnected subnetworks for enabling end stations on the distinct subnetworks to communicate directly without the use of router devices, the switch comprising:a subnet mask and a plurality of subnets specified by a user via a user interface, the subnet mask being larger in value than a subnet mask of a source end station on a first distinct subnetwork, said source end station having a network layer address, and a data link layer address, the subnet mask of the switch also being larger in value than a subnet mask of a destination end station on a second distinct subnetwork, said destination end station having a network layer address, and a data link address;packet analysis and forwarding programming code, operating on a processing unit in said switch, for analyzing a multicast packet, having both network layer information and a medium access control (MAC) address, received from said source end station, and selectively forwarding said multicast packet to all ports associated with a destination subnet; anda subnet to port mapping table for storing a mapping of said plurality of subnets to a plurality of ports associated with each said subnet;the packet analysis and programming code also analyzing the MAC address of the multicast packet to make a determination of whether the packet is an all stations multicast message, and if the code determines that the multicast packet is an all stations multicast message, the code then analyzes the network layer information to determine whether the multicast packet is an address resolution protocol packet, and if the code determines that the multicast packet is an address resolution protocol packet, the code then makes a forwarding decision for the multicast packet based upon subnet information derived from the network layer information.