Switching MAC fields for guests on a shared host

摘要

In an internal network on a shared host (100) in which internal Media Access Control (MAC) and Internet Protocol (IP) addresses are assigned by a Dynamic Host Configuration Protocol (DHCP), guests (104-108) can communicate with an external network (110) without requiring Network Address Translation (NAT), in which these addresses are replaced by those of the host and recorded in a table to allow correct routing of return packets, by using auxiliary addresses. The host determines whether the target MAC address (301, 408 or 510) is internal and, if so, switches it with the source MAC address (302, 406 or 509) thus preventing loopback (fig, 5A) of data packets sent between guests on the host, which will necessarily have the same MAC addresses, and possibly IP addresses (fig. 2), in the source and target fields of their Ethernet (fig. 3) or Address Resolution Protocol (ARP, fig. 4) headers.