Systems and methods are described for communications between computing devices via a stateless high-volume network address translation (“NAT”) service. The stateless high-volume NAT service manages high volumes of connections between networks by encoding at least part of the information needed to manage a connection in an encoded IPv6 address, which is then used by a NAT device or application as its sending address when relaying data from a source to a destination. The encoded IPv6 address may contain information such as the IPv4 address of the source, the IPv4 address of the destination, the protocol used to communicate, the source and destination ports, and the like. When the destination sends a response to the encoded IPv6 address, the NAT device decodes the IPv6 address to obtain the encoded information, and then uses that information to deliver the response to the source.

Systems and methods are described for communications between computing devices via a stateless high-volume network address translation (“NAT”) service. The stateless high-volume NAT service manages high volumes of connections between networks by encoding at least part of the information needed to manage a connection in an encoded IPv6 address, which is then used by a NAT device or application as its sending address when relaying data from a source to a destination. The encoded IPv6 address may contain information such as the IPv4 address of the source, the IPv4 address of the destination, the protocol used to communicate, the source and destination ports, and the like. When the destination sends a response to the encoded IPv6 address, the NAT device decodes the IPv6 address to obtain the encoded information, and then uses that information to deliver the response to the source.

The method for an automated IPv6/IPv4 fallback approach in proxy networks is presented. In some embodiments, the method comprises receiving, at a proxy server, a request from a client executing on a client computer for access to a target computer; determining identification-information of the client; determining an address pair including an IPv6 address and an IPv4 address of the proxy server; assigning the address pair to the identification-information of the client; establishing a first communications connection between the client computer and the proxy server using one of IP addresses included in the address pair, and a second communications connection between the proxy server and the target computer using one of IP addresses included in the address pair; and facilitating a network packet flow between the client computer and the target computer using the first communications connection and the second communications connection.

The method for an automated IPv6/IPv4 fallback approach in proxy networks is presented. In some embodiments, the method comprises receiving, at a proxy server, a request from a client executing on a client computer for access to a target computer; determining identification-information of the client; determining an address pair including an IPv6 address and an IPv4 address of the proxy server; assigning the address pair to the identification-information of the client; establishing a first communications connection between the client computer and the proxy server using one of IP addresses included in the address pair, and a second communications connection between the proxy server and the target computer using one of IP addresses included in the address pair; and facilitating a network packet flow between the client computer and the target computer using the first communications connection and the second communications connection.

A MAP-T system that shares an IPv4 address with one or more other MAP-T systems identifies low latency (LL) traffic for an upstream and a downstream perspective by enhancing NAT of ports using MAP-T rules. The MAP-T rules provide a range of transport ports with a transport slice providing for a subdivision of the transports into a subnet range so as to isolate certain ports for mapping LL traffic. An access point device and a cable modem of the MAP-T system are configured so as to appropriately transform any received traffic so as to properly direct the traffic.

A MAP-T system that shares an IPv4 address with one or more other MAP-T systems identifies low latency (LL) traffic for an upstream and a downstream perspective by enhancing NAT of ports using MAP-T rules. The MAP-T rules provide a range of transport ports with a transport slice providing for a subdivision of the transports into a subnet range so as to isolate certain ports for mapping LL traffic. An access point device and a cable modem of the MAP-T system are configured so as to appropriately transform any received traffic so as to properly direct the traffic.

Methods and systems for an accelerated and offload dual border relay. A method includes receiving, by a hardware border relay from a network device, an Internet Protocol (IP) packet, determining, by the hardware border relay, a packet type of the IP packet, translating, by the hardware border relay provisioned with IPv6 transition technology rules, the IP packet to a hardware translated IP packet when the IP packet is a first type, translating, by the offload border relay provisioned with MAP-T rules, the IP packet to an offload translated IP packet when the IP packet is a second type, transmitting, by the offload border relay to the hardware border relay, the offload translated IP packet when the IP packet is the second type, and transmitting, by the hardware border relay, one of the offload translated IP packet and the hardware translated IP packet to another network device.

Methods and systems for an accelerated and offload dual border relay. A method includes receiving, by a hardware border relay from a network device, an Internet Protocol (IP) packet, determining, by the hardware border relay, a packet type of the IP packet, translating, by the hardware border relay provisioned with IPv6 transition technology rules, the IP packet to a hardware translated IP packet when the IP packet is a first type, translating, by the offload border relay provisioned with MAP-T rules, the IP packet to an offload translated IP packet when the IP packet is a second type, transmitting, by the offload border relay to the hardware border relay, the offload translated IP packet when the IP packet is the second type, and transmitting, by the hardware border relay, one of the offload translated IP packet and the hardware translated IP packet to another network device.

A first network device associated with a network may establish an Internet protocol version 6 Multiprotocol BGP session with a second network device associated with the network. The first network device and second network device are both capable of forwarding both IPv4 and IPv6 packets with only an IPv6 address configured on the interface of both the first network device and second network device. The first network device may exchange Multiprotocol Reachability capability with second network device for corresponding 2-tuple Address Family Identifier/Subsequent Address Family Identifier. The first network device may advertise Internet protocol version 4 network layer reachability information and may advertise Internet protocol version 6 network layer reachability information with IPv6 extended next hop encoding using Internet Assigned Numbering Authority assigned capability code value 5 to second network device.

Techniques are described for managing communications between multiple computing nodes, such as for computing nodes that are part of managed virtual computer networks provided on behalf of users or other entities. In some situations, one or more of the computing nodes of a managed virtual computer network is configured to perform actions to extend capabilities of the managed virtual computer network to other computing nodes that are not part of the managed virtual computer network, such as by forwarding communications between computing nodes of the managed virtual computer network and the other external computing nodes so as to enable the other external computing nodes to participate in the managed virtual computer network. In some situations, the computing nodes may include virtual machine nodes hosted on one or more physical computing machines or systems, such as by or on behalf of one or more users.