Methods and system for returning requests with javascript for clients before passing a request to a server

A network traffic management apparatus, comprising memory comprising programmed instructions stored thereon and one or more processors configured to be capable of executing the stored programmed instructions to:

• intercept an initial request from a client for a resource hosted by a server before the initial request reaches the server;
• respond to the intercepted initial request by sending a client-side script to the client, the client-side script including a computational challenge that when executed by the client causes the client to generate a client-side execution result that is included with a subsequent request from the client for the resource, wherein the computational challenge includes automatically obtaining information about a user of the client from the client, the computational challenge selected from among a plurality of computational challenges based on a variable length of script execution time and a determined latency of a plurality of responses received from the server;
• intercept the subsequent request from the client before the subsequent request reaches the server;
• and
• in response to determining the intercepted client-side execution result matches an answer to the computational challenge, forward the subsequent request to the server.

A non-transitory computer readable medium having stored thereon instructions for mitigating network-based attacks comprising executable code which when executed by one or more processors, causes the one or more processors to:

• intercept an initial request from a client for a resource hosted by a server before the initial request reaches the server;
• respond to the intercepted initial request by sending a client-side script to the client, the client-side script including a computational challenge that when executed by the client causes the client to generate a client-side execution result that is included with a subsequent request from the client for the resource, wherein the computational challenge includes automatically obtaining information about a user of the client from the client, the computational challenge selected from among a plurality of computational challenges based on a variable length of script execution time and a determined latency of a plurality of responses received from the server;
• intercept the subsequent request from the client before the subsequent request reaches the server;
• and
• in response to determining the intercepted client-side execution result matches an answer to the computational challenge, forward the subsequent request to the server.

A network traffic management system, comprising one or more traffic management apparatuses, client devices, or server devices, the network traffic management system comprising memory comprising programmed instructions stored thereon and one or more processors configured to be capable of executing the stored programmed instructions to:

• intercept an initial request from a client for a resource hosted by a server before the initial request reaches the server;
• respond to the intercepted initial request by sending a client-side script to the client, the client-side script including a computational challenge that when executed by the client causes the client to generate a client-side execution result that is included with a subsequent request from the client for the resource, wherein the computational challenge includes automatically obtaining information about a user of the client from the client, the computational challenge selected from among a plurality of computational challenges based on a variable length of script execution time and a determined latency of a plurality of responses received from the server;
• intercept the subsequent request from the client before the subsequent request reaches the server;
• and
• in response to determining the intercepted client-side execution result matches an answer to the computational challenge, forward the subsequent request to the server.