Foundry Networks, Inc.

Brocade Communications Systems, Inc.

Gigamon Inc.

David Chun Ying Cheung

Rajkumar Ramniranjan Jalan

Ivy Pei-Shan Hsu

Ronald W Szeto

Sunanda Lakshmi Kommula

Fushan Allan Yuan

Dale L Guise, Jr

Prajakta S Joshi

Sridhar J Devarapalli

A proxy device coupled to a network receives communications between a client and a server on the network. The proxy device operates transparently to the client and the server, while coupled to receive and process the communications from a node on the network via a network port in a one-armed configuration. The proxy device communicates packets of the communications with an external tool coupled to the proxy device via a tool port and operates transparently to the nod and the tool. In certain embodiments, the tool may be a network security device, such as a firewall.

One-armed inline decryption/encryption proxy operating in transparent bridge mode

A global server load balancing (GSLB) switch serves as a proxy to an authoritative DNS communicates with numerous site switches which are coupled to host servers serving specific applications. The GSLB switch receives from site switches operational information regarding host servers within the site switches neighborhood. When a client program requests a resolution of a host name, the GSLB switch, acting as a proxy of an authoritative DNS, returns one or more ordered IP addresses for the host name. The IP addresses are ordered using metrics that include the information collected from the site switches. In one instance, the GSLB switch places the address that is deemed 'best' at the top of the list.

Global server load balancing

A global server load-balancing (GSLB) switch serves as a proxy to an authoritative DNS and communicates with numerous site switches that are coupled to host servers serving specific applications. The GSLB switch receives from site switches operational information regarding host servers within the site switches neighborhood. This operational information includes health check information that is remotely obtained in a distributed manner from remote metric agents at the site switches. When a client program requests a resolution of a host name, the GSLB switch, acting as a proxy of an authoritative DNS, returns one or more ordered IP addresses for the host name. The IP addresses are ordered using metrics, including the health check metric that evaluates these IP addresses based on the health check information communicated to the GSLB switch in a distributed manner by the distributed health check site switches. In one instance, the GSLB switch places the address that is deemed 'best' at the top of the list.

Distributed health check for global server load balancing

Transaction rate limiting is provided to monitor new connections. If the number of new connections requested by a particular client exceeds a predetermined threshold value, then the client may be frozen out for a configured period of time. By denying access for the configured period of time, the client is prevented from monopolizing a particular client. Additionally, if the client does have malicious intent, a denial of service attack may be thwarted. The denial of service may be accomplished without alerting the client. This prevents a malicious client from regrouping and attempting an assault via a different mechanism.

Transaction rate limiting

Each service in a computer network may have a connection rate limit. The number of new connections per time period may be limited by using a series of rules. In a specific embodiment of the present invention, a counter is increased each time a server is selected to handle a connection request. For each service, connections coming in are tracked. Therefore, the source of connection-request packets need not be examined. Only the destination service is important. This saves significant time in the examination of the incoming requests. Each service may have its own set of rules to best handle the new traffic for its particular situation. For server load balancing, a reset may be sent to the source address of the new connection request. For transparent cache switching, the connection request may be forwarded to the Internet.

Connection rate limiting for server load balancing and transparent cache switching

A global server load-balancing (GSLB) switch serves as a proxy to an authoritative DNS and communicates with numerous site switches that are coupled to host servers serving specific applications. The GSLB switch receives from site switches operational information regarding host servers within the site switches neighborhood. When a client program requests a resolution of a host name, the GSLB switch, acting as a proxy of an authoritative DNS, returns one or more ordered IP addresses for the host name. The IP addresses are ordered using metrics that include the information collected from the site switches. In one instance, the GSLB switch places the address that is deemed 'best' at the top of the list.

Each service in a computer network may have a connection rate limit. The number of new connections per time period may be limited by using a series of rules. In a specific embodiment of the present invention, a counter is increased each time a server is selected to handle a connection request. For each service, connections coming in are tracked. Therefore, the source of connection-request packets need not be examined. Only the destination service is important. This saves significant time in the examination of the incoming requests. Each service may have its own set of rules to best handle the new traffic for its particular situation.

Growing community of inventors

San Jose, CA, United States of America

David Chun Ying Cheung