US 9,319,476 B2 · Resilient TCP splicing for proxy services

Abstract

A transparent proxy device includes an ingress, an egress, and an application proxy. The ingress and the egress operate up to a layer four communication layer. The transparent proxy device is configured to establish spliced connections in relation to end devices. The spliced connections include layer four connections between the ingress and the application proxy and the application proxy and the egress. The transparent proxy device is configured to maintain an end-to-end connection in relation to the end devices even when the application proxy fails.

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Claims20

Dependent claims

A method comprising:

receiving, by an ingress of a transparent proxy device and from a first end device, a first request that includes a first initial sequence number and options, to establish a layer four connection with a second end device, wherein the ingress operates at a layer lower than an application layer of the transparent proxy device;
learning, by the ingress of the transparent proxy device, the first initial sequence number of the first request;
transmitting, by the ingress of the transparent proxy device, the first request, to an egress of the transparent proxy device, wherein the first request bypasses an application proxy of the transparent proxy device and wherein the application proxy operates at the application layer of the transparent proxy device;
receiving, by an egress of the transparent proxy device and from the ingress, the first request, wherein the egress operates at the layer lower than the application layer of the transparent proxy device;
learning, by the egress of the transparent proxy device, the first initial sequence number of the first request;
receiving, by the egress of the transparent proxy device and from the second end device, a first acknowledgement for the first request and options, wherein the first acknowledgement includes a second initial sequence number;
learning, by the egress of the transparent proxy device, the second initial sequence number;
transmitting, by the egress of the transparent proxy device, the first acknowledgement, to the ingress of the transparent proxy device, wherein the first acknowledgement bypasses the application proxy of the transparent proxy device;
learning, by the ingress of the transparent proxy device, the second initial sequence number;
transmitting, by the ingress to the application proxy of the transparent proxy device, a second request, which includes the first initial sequence number and options negotiated between the first end device and the second end device, to establish a layer four connection between the ingress and the application proxy, in response to receiving the first acknowledgement;
establishing a layer four connection between the ingress and the first end device based on a second acknowledgement from the first end device;
establishing the layer four connection, between the ingress and the application proxy, in response to receiving the second acknowledgement;
establishing a layer four connection between the application proxy and the egress;
and
establishing the layer four connection between the egress and the second end device based on the second acknowledgement.

12 more elements

A proxy device comprising:

an ingress layer including a first transmitter and a first receiver, wherein the ingress layer operates up to a layer four communication layer;
an egress layer including a second transmitter and a second receiver, wherein the egress layer operates up to a layer four communication layer;
an application proxy, wherein the application proxy operates at an application communication layer;
a memory, wherein the memory stores instructions;
and
a processor, wherein the processor executes the instructions to:
receive, via the first receiver of the ingress layer and from a first end device, a first request that includes a first initial sequence number and options, to establish a layer four connection with a second end device;
learn, by the ingress layer, the first initial sequence number of the first request;
transmit, via the first transmitter of the ingress layer, the first request, to the egress layer, wherein the first request bypasses the application proxy;
receive, via the second receiver of the egress layer and from the ingress layer, the first request;
learn, by the egress layer, the first initial sequence number of the first request;
receive, via the second receiver of the egress layer and from the second end device, a first acknowledgement for the first request and options, wherein the first acknowledgement includes a second initial sequence number;
learn, by the egress layer, the second initial sequence number;
transmit, via the second transmitter of the egress layer, the first acknowledgement, to the ingress layer, wherein the first acknowledgement bypasses the application proxy;
learn, by the ingress layer, the second initial sequence number;
transmit, via the first transmitter of the ingress layer to the application proxy, a second request, which includes the first initial sequence number and options negotiated between the first end device and the second end device, to establish a layer four connection between the ingress layer and the application proxy, in response to receiving the first acknowledgement;
establish a first, layer four connection between the ingress layer and the first end device based on a second acknowledgement from the first end device;
establish a second, layer four connection, between the ingress layer and the application proxy, in response to receiving the second acknowledgement;
establish a third, layer four connection between the application proxy and the egress layer;
and
establish a fourth, layer four connection between the egress layer and the second end device based on the second acknowledgement.

18 more elements

A non-transitory computer-readable storage medium that stores instructions, executable by a processor of a computational device that includes an ingress layer that operates up to a layer four communication layer, an egress layer that operates up to a layer four communication layer, and an application proxy that operates at an application communication layer, which when executed cause the computational device to:

receive, by the ingress layer and from a first end device, a first request that includes a first initial sequence number and options, to establish a layer four connection with a second end device;
learn, by the ingress layer, the first initial sequence number of the first request;
transmit, by the ingress layer, the first request, to the egress layer, wherein the first request bypasses the application proxy;
receive, by the egress layer and from the ingress layer, the first request;
learn, by the egress layer, the first initial sequence number of the first request;
receive, by the egress layer and from the second end device, a first acknowledgement for the first request and options, wherein the first acknowledgement includes a second initial sequence number;
learn, by the egress layer, the second initial sequence number;
transmit, by the egress layer, the first acknowledgement, to the ingress layer, wherein the first acknowledgement bypasses the application proxy;
learn, by the ingress layer, the second initial sequence number;
transmit, by the ingress layer to the application proxy, a second request, which includes the first initial sequence number and options negotiated between the first end device and the second end device, to establish a layer four connection between the ingress layer and the application proxy, in response to receiving the first acknowledgement;
establish a first, layer four connection between the ingress layer and the first end device based on a second acknowledgement from the first end device;
establish a second, layer four connection, between the ingress layer and the application proxy, in response to receiving the second acknowledgement;
establish a third, layer four connection between the application proxy and the egress layer;
and
establish a fourth, layer four connection between the egress layer and the second end device based on the second acknowledgement.

12 more elements

Dependencies are inferred from the claim text.

Description8,499 words

Summary83 words

#Transparent application layer proxies, which terminate Transmission Control Protocol (TCP) connections, are used in the Internet for various purposes. For example, a Hypertext Transfer Protocol (HTTP) proxy or a Radio Access Network (RAN) TCP optimization proxy situated behind a RAN gateway may be implemented. In order for a proxy to be transparent, the proxy acts as a router in the network. Unfortunately, if the proxy crashes or a route to the proxy becomes unavailable due to a network failure, service disruption may occur.

Brief description of the drawings8 figures

#FIG. 1A is a diagram illustrating an exemplary environment in which an exemplary embodiment of resilient TCP splicing for proxy service may be implemented;

#FIG. 1B is a diagram illustrating exemplary elements of a transparent proxy depicted in FIG. 1A;

#FIGS. 2A-2E are diagrams illustrating exemplary messaging flows pertaining to an exemplary embodiment of resilient TCP splicing;

Detailed description8,233 words

#The following detailed description refers to the accompanying drawings. The same reference numbers in different drawings may identify the same or similar elements.

#Transparent application proxies are often deployed on a network (e.g., a service, enterprise network) that implements resilient multipath network connectivity within the network to provide continuous (e.g., 24 hours, 7 days a week) access and availability to the proxy services. Unfortunately, irrespective of alternate network paths, end-users may experience an interruption of a proxy service when a proxy crashes or the proxy is not accessible due to a network failure. As a result, end-users may experience a service disruption.

#As described herein, a resilient TCP splicing mechanism is introduced. The resilient TCP splicing mechanism may avoid end-to-end TCP connection failures to a service even when a proxy or a route to the proxy becomes unavailable.

Facts

Application

13/903,046Filed 28 May 2013

Published

US 2014/0359052 A14 Dec 2014

Granted

19 Apr 2016

Term ends

25 May 2034

Estimated · how

20 years from earliest known nonprovisional domestic filing plus recorded patent term adjustment, including 362 days of adjustment. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination.

Classification4 codes

H04L 69/16
Network arrangements, protocols or services independent of the application payload and not provided for in the other groups of this subclass:…
H04L 67/56
Network services: provisioning of proxy services
H04L 41/0293
Using web services for network management, e.g. simple object access protocol [SOAP]: for accessing web services by means of a binding…
H04L
Digital communication

Timeline

28 May 2013Application filedUS 13/903,046
28 May 2013Assigned to Verizon Patent and Licensing Inc.assignment of assignor's interest
4 Dec 2014PublishedUS 2014/0359052 A1
19 Apr 2016GrantedUS 9,319,476 B2
12 Oct 2026TodayWithin its term
25 May 2034Term endsEstimated, includes 362 days of adjustment

Resilient TCP splicing for proxy services

Life of this patent

Resilient TCP splicing for proxy services

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims20

Description8,499 words

Drawings

Classification4 codes

Life of this patent

Description8,499 words