Reliable, high-throughput, high-performance transport and routing mechanism for arbitrary data flows

• US 7,660,296 B2
• Filed: 12/30/2005
• Issued: 02/09/2010
• Est. Priority Date: 12/30/2005
• Status: Active Grant

• Current Assignee: Akamai Technologies, Inc.
• Original Assignee: Akamai Technologies, Inc.
• Inventors: Stodolsky, Daniel, Fletcher, Gregory, Champagne, Andrew F., Afergan, Michael M.
• Primary Examiner(s): Yao; Kwang B
• Assistant Examiner(s): Lai; Andrew
• Application Number:
  US11/323,342
• Publication Number:
  US 20070153782A1
• Time in Patent Office: 1,502 Days
• Field of Search: 370/230, 370/338, 370/349, 370/389, 370/465, 370/351, 370/397, 370/409, 709/223, 709/225, 709/229, 707/100
• US Class Current: 370/352
• CPC Class Codes: H04J 3/1617 carrying packets or ATM cells
• CPC Class Codes: H04L 12/4633 Interconnection of networks using encapsulation techniques, e.g. tunneling
• CPC Class Codes: H04L 2101/668 Internet protocol [IP] address subnets
• CPC Class Codes: H04L 41/5009 Determining service level performance parameters or violations of service level contracts, e.g. violations of agreed response time or mean time between failures [MTBF]
• CPC Class Codes: H04L 41/5077 wherein the managed service relates to simple transport services, i.e. providing only network infrastructure
• CPC Class Codes: H04L 41/5096 wherein the managed service relates to distributed or central networked applications
• CPC Class Codes: H04L 43/00 Arrangements for monitoring or testing data switching networks
• CPC Class Codes: H04L 43/0829 Packet loss
• CPC Class Codes: H04L 43/0852 Delays
• CPC Class Codes: H04L 43/16 Threshold monitoring
• CPC Class Codes: H04L 61/2567 for reachability, e.g. inquiring the address of a correspondent behind a NAT server
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]
• CPC Class Codes: H04L 61/5007 Internet protocol [IP] addresses
• CPC Class Codes: H04L 67/01 Protocols
• CPC Class Codes: H04L 67/10 in which an application is distributed across nodes in the network software deployment G06F8/60; multiprogramming arrangements G06F9/46

Abstract

The present invention leverages an existing content delivery network infrastructure to provide a system that enhances performance for any application that uses the Internet Protocol (IP) as its underlying transport mechanism. An overlay network comprises a set of edge nodes, intermediate nodes, and gateway nodes. This network provides optimized routing of IP packets. Internet application users can use the overlay to obtain improved performance during normal network conditions, to obtain or maintain good performance where normal default BGP routing would otherwise force the user over congested or poorly performing paths, or to enable the user to maintain communications to a target server application even during network outages.

Claims

1. A method of providing a plurality of client machines remote access to an application executing on a target server, wherein each client machine communicates with the application over the Internet using Internet Protocol (IP) transport, comprising:

establishing an overlay network, the overlay network comprising at least one or more edge regions, a set of intermediate regions, and one or more gateway regions, wherein each edge region, each intermediate region, and each gateway region comprises one or more servers that receive and process communications over IP;

for each client machine, and upon DNS resolution of a hostname associated with the application, associating each such client machine with a virtual IP address associated with a given server in a given edge region;

at the given server within the given edge region;

for each IP-based request data packet to be communicated between the client machine and the application, encapsulating the request data packet, duplicating the request data packet as encapsulated, and forwarding the request data packet as encapsulated to a given server at a gateway region, wherein the request data packet is forwarded to the given server at the gateway region over each of a set of paths that include at least one intermediate region, the set of paths including at least first and second paths from the given edge region to the gateway region that do not share a same intermediate region;

at the given server within the gateway region, processing received data to recover the request data packet, applying a network address translation to the request data packet as recovered and forwarding the request data packet to the target server for further processing by the application, wherein the network address translation also applies a source NAT to the packet before it is forwarded to the target server and an IP response data packet to the request data packet is delivered through the overlay network to the server having the virtual IP address.

2. The method as described in claim 1 wherein the virtual IP address is obtained by having the client machine execute a query against the hostname.

3. The method as described in claim 2 wherein the hostname is obtained by aliasing a domain associated with the application.

4. The method as described in claim 3 further including the step of de-aliasing the domain associated with the application upon a given failure condition.

5. The method as described in claim 1 wherein the given edge region is a best performing edge region at the time of the DNS resolution.

6. The method as described in claim 1 wherein the network address translation performs a destination NAT that translates the virtual IP address to an IP address of the target server.

7. The method as described in claim 1 further including the steps of receiving the response data packet at the gateway, encapsulating the response data packet, duplicating the response data packet as encapsulated, and forwarding the response data packet as encapsulated over a set of paths.

8. The method as described in claim 7 further including the steps of:

at the server having the virtual IP address, processing received data to recover the response data packet, and forwarding the response data packet to the client machine.

9. The method as described in claim 1 wherein the first and second paths are identified as a function of byte load injected into the overlay network by one or more edge regions and load on at least one intermediate region.