Load balancing array system with URL modification so that content is served by a content delivery network

• US 8,504,719 B2
• Filed: 06/07/2010
• Issued: 08/06/2013
• Est. Priority Date: 03/10/2000
• Status: Expired due to Fees

• Current Assignee: Akamai Technologies, Inc.
• Original Assignee: Akamai Technologies, Inc.
• Inventors: Swildens, Eric Sven-Johan
• Primary Examiner(s): Patel, Haresh N
• Application Number:
  US12/795,521
• Publication Number:
  US 20100251008A1
• Time in Patent Office: 1,156 Days
• Field of Search: 709217-228, 709200-203, 709/238, 718/105
• US Class Current: 709/238
• CPC Class Codes: H04L 63/0471 applying encryption by an intermediary, e.g. receiving clear information at the intermediary and encrypting the received information at the intermediary before forwarding
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/10015 Access to distributed or replicated servers, e.g. using brokers
• CPC Class Codes: H04L 67/1008 based on parameters of servers, e.g. available memory or workload monitoring of computer activity G06F11/30
• CPC Class Codes: H04L 67/1023 based on a hash applied to IP addresses or costs
• CPC Class Codes: H04L 67/1027 Persistence of sessions during load balancing
• CPC Class Codes: H04L 67/1034 Reaction to server failures by a load balancer
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A decrypting load balancing array system uses a Pentaflow approach to network traffic management that extends across an array of Decrypting Load Balancing Array (DLBA) servers sitting in front of back end Web servers. One of the DLBA servers acts as a scheduler for the array through which all incoming requests are routed. The scheduler routes and load balances the traffic to the other DLBA servers (including itself) in the array. Each DLBA server routes and load balances the incoming request packets to the appropriate back end Web servers. Responses to the requests from the back end Web servers are sent back to the DLBA server which forwards the response directly to the requesting client.

Claims

1. A method for routing packets through a load balancing array of servers across a network in a computer environment, comprising:

in response to receiving a request packet from a requesting client via an IP address at a scheduler among a load balancing array of servers, the scheduler routing and load balancing the request packet to a load balancing server among the load balancing array of servers;

in response to receiving the request packet at the load balancing server, the load balancing server decrypting information in the request packet and then routing and load balancing the request packet, with the decrypted information, to a back end Web server among a cluster of back end Web servers, wherein the back end Web server'"'"'s response packet to the request packet is received at the load balancing server, the response packet containing at least one portion of an outgoing markup language page; and

in response to receiving the response packet with the at least one portion of the outgoing markup language page at the load balancing server, the load balancing server parsing the at least one portion of an outgoing markup language page in the response packet to identify content served by a content delivery network, modifying one or more URLs for the content in the at least one portion of the markup language page so that the content is served from the content delivery network in response to requests from requesting clients, and sending the response packet to the requesting client such that the response packet does not go through the scheduler;

wherein the scheduler and the load balancing server that perform the steps recited herein each comprise a computer hardware device.

2. The method of claim 1, wherein the scheduler routes and load balances client request packets to itself.

3. The method of claim 1, further comprising:

determining by the load balancing server, a MAC address of the back end Web server;

changing a MAC address in the request packet to the MAC address of the back end Web server.

4. The method of claim 1, further comprising:

detecting failure of the scheduler; and

electing a load balancing server among the load balancing array of servers as a new scheduler.

5. The method of claim 1, wherein the scheduler detects failure of load balancing servers among the load balancing array of servers, and wherein the scheduler stops routing packets to failed load balancing servers.

6. The method of claim 1, wherein the load balancing server schedules sessions to back end Web servers based on a cookie or session ID.

7. The method of claim 1, wherein the load balancing server uses cookie injection to map a client to a specific back end Web server.

8. A system of load balancing servers interconnected across a network in a computer environment, the system comprising:

a scheduler among a load balancing array of servers that is programmed to, in response to receiving a request packet from a requesting client via an IP address, route and load balance the request packet to a load balancing server among the load balancing array of servers;

the load balancing server among the load balancing array of servers is programmed to, in response to receiving the request packet, decrypt information in the request packet and then route and load balance the request packet, with the decrypted information, to a back end Web server among a cluster of back end Web servers, wherein the back end Web server'"'"'s response packet to the request packet is received at the load balancing server, the response packet containing at least one portion of an outgoing markup language page; and

the load balancing server is programmed to, in response to receiving the response packet with the at least one portion of the outgoing markup language page, parse the at least one portion of an outgoing markup language page in the response packet to identify content served by a content delivery network, modify one or more URLs for the content in the at least one portion of the markup language page so that the content is served from the content delivery network in response to requests from requesting clients, and send the response packet to the requesting client such that the response packet does not go through the scheduler;

the scheduler, the load balancing server, and the back end Web server each comprise one or more hardware processors and computer memory holding computer program instructions for execution by the one or more hardware processors.

9. The system of claim 8, wherein the scheduler is programmed to route and load balance client request packets to itself.

10. The system of claim 8, further comprising:

a logic, at the load balancing server, that determines a MAC address of the back end Web server;

a logic, at the load balancing server, that changes a MAC address in the request packet to the MAC address of the back end Web server.

11. The system of claim 8, further comprising:

a logic, at the load balancing server, that detects failure of the scheduler; and

a logic, at the load balancing server, that elects a load balancing server among the load balancing array of servers as a new scheduler.

12. The system of claim 8, wherein the scheduler is programmed to detect failure of load balancing servers among the load balancing array of servers, and wherein the scheduler is programmed to stop routing packets to failed load balancing servers.

13. The system of claim 8, wherein the load balancing server is programmed to schedule sessions to back end Web servers based on a cookie or session ID.

14. The system of claim 8, wherein the load balancing server is programmed to use cookie injection to map a client to a specific back end Web server.