Cisco Technology, Inc.

Senthil M Sivakumar

Siva S Jayasenan

Kaushik Pratap Biswas

Mahadev Somasundaram

Suresh Satapati

Anantha Ramaiah

Mark Denny

Michael J Sullenberger

Alpesh S Patel

Doron Oz

Todd Short

Melinda L Shore

Yongming Zhang

Markus G Hies

Dushyant Joshi

Thimmappa Thejaswi

Rohit Uberoi

Jieping Chen

Suresh K Satapati

In one embodiment, excess committed network appliance resources are shared for providing services within a network appliance. One approach maintains service resources in a committed service resource pool and one or more other pools of service resources. Service resources are taken from a corresponding pool as needed. Service resources are reallocated to the committed resource pool as needed to ensure that service resources are available to service corresponding packet streams at their corresponding committed rate. Examples of such services provided by a network appliance include, but are not limited to, network address translation (NAT), firewall, Internet Protocol Security (IPsec), virtual private network (VPN), or deep packet inspection (DPI) services.

Sharing excess committed network appliance resources

Techniques are provided to facilitate faster live migration of a virtual server from one physical server to another physical server by pausing IO activity of the virtual server and slowing memory state changes for CPU-bound activity of the virtual server during the live migration.

Minimizing latency in live virtual server migration

Disclosed are methods and apparatus for handling requests for data from a private network. In general terms, a client who wishes access to secure data, such as a secure web page, from a private network establishes a secure connection with a secure server, such as a secure socket layer (SSL) server, of the private network. The secure server then downloads a software program for handling data requests (made by the client for data located within the private network) to the client. This software program is downloaded automatically by the secure server to the client when the client initiates a secure connection with such secure server. The downloaded software program is generally configured to modify data requests (e.g., by performing a URL substitution) sent from the client to an internal server of the private network such that the data requests are redirected to the secure server. The secure server then processes the data request (e.g., by retrieving the data from the appropriate internal server).

Solution for handling URL-substitution for data access in a private network architecture

A method of preventing network denial of service attacks by early discard of out-of-order segments comprises creating a reassembly queue for a connection between a first network node and a second network node, wherein the connection has been established based on a transport-layer network protocol, the reassembly queue having a size based on a buffer size of an input interface with which the connection is associated. As out-of-order data segments arrive on the connection, and before other processing of the segments, whether the reassembly queue is full is determined, and the out-of-order segments are discarded if the reassembly queue is full. The size of the reassembly queue is automatically changed in response to one or more changes in any of network conditions and device resources.

Preventing network denial of service attacks by early discard of out-of-order segments

Disclosed are methods and apparatus for handling data containing embedded addresses. In general terms, prior to transmission of data having an embedded address or port, an initiating host sends a NAT Probe to an end-host with which the initiating host wishes to communicate. The NAT Probe includes the embedded address or port and a type indicating that translation of the address and/or port is requested if needed. As the NAT Probe traverses through one or more NAT devices as it is transmitted to the end-host, each NAT device is enabled to recognize the NAT Probe type and translate the embedded address and/or port, depending upon the individual NAT device's configuration. When the NAT Probe reaches the final hop NAT device or end-host, a NAT Probe Reply is sent back to the initiating host. The NAT Probe Reply contains a translated embedded address and/or port which is compatible with the end-host's network. The NAT Probe Reply also contains a type which differs from the type of the NAT Probe. As the NAT Probe Reply traverses back through the same NAT devices, the NAT device recognize the type of the NAT Probe Reply and do not translate the embedded address and/or port.

Method and apparatus for handling embedded addresses in data sent through multiple network address translation (NAT) devices

Methods and apparatuses for distributing network address translation. By having a gateway inform inside devices of global addresses, the gateway can avoid performing many functions of a traditional NAT box. Specifically, an inside device is informed of a global address shared by all devices on the inside device's network segment. Each device on that segment would be assigned a range of ports to distinguish messages from separate devices that use the same global address.

Method and apparatus for distributed network address translation processing

Communicating packets along a control channel and a media channel includes receiving at a network address translator a first message having a first internal address from a first communication device. The first internal address is translated to a first external control address operable to route a control packet along a control channel. A second message having a first embedded media address is received from the first communication device. The first embedded media address is translated to a first external media address operable to route a media packet along a media channel.

Communicating packets along a control channel and a media channel

Disclosed are methods and apparatus for facilitating reliable session based communication with a local host via a subnet of redundant network devices that also implement network address translation (NAT) or the like. In general, embodiments of the present invention include mechanisms for reestablishing access to a local host after the local host's active network device has failed and been replaced by a new active network device with an address space that differs from the failed network device. In this invention, the network devices associated with the same local host also implement NAT, or the like. In brief, for each of its associated local hosts, the new active network device causes an address server to be updated with a new public address that is assigned from its address space to the local host. This update allows other remote hosts access to the local hosts by obtaining the updated address information from the address server. Communication sessions that were established prior to the failing active network device may also be retained by the new active network device. In this aspect, for each ongoing particular session between a remote host and a local host of the new active network device, the new active network device updates the remote host with a new public address assigned to local host for use in the particular session.

Mechanisms for providing connectivity in NAT redundant/fail-over scenarios in unshared address-space

Disclosed are methods and apparatus for facilitating translation of packet addresses (or ports) by one or more translation devices (e.g., Network Address Translation or NAT devices) using a specialized protocol to handle an address (or port) that is used to form part of a payload. In one implementation, this specialized protocol is referred to as Network Layer Signaling (NLS). As a packet traverses along a path containing one or more translation devices, each translation device is configured to translate an address (or port) of such packet's IP header if the packet is traversing between different domains (e.g., traversing between a private and public domain or between two different private domains). One or more of these translation devices may also be configured to implement the specialized protocol which includes translation device traversal mechanisms for detecting whether the traversal path contains a translation device that fails to implement such specialized protocol. When such a failure is detected, recovery mechanisms are also triggered.

Mechanisms for detection of non-supporting NAT traversal boxes in the path

Approaches to recover from faults associated with multi-homed clients having transport protocol connections that pass through network address translators are disclosed. In one approach, context information for a connection, between a first host and a second host, referencing one of several multi-homed network addresses of the first host, is automatically re-used when the second host switches to a different address of the first host, for example, when the first host becomes unavailable at the original address. Embodiments support seamless switchover of SCTP connections over NAT devices.

Method and apparatus for detecting and recovering from faults associated with transport protocol connections across network address translators

A method for transparently sharing at least one IPv4 address among a plurality of hosts wherein at least a first host of the plurality of hosts uses the IPv4 protocol and wherein at least a second host of the plurality of hosts uses an IPv6 protocol is provided. A first data having a first source address and a first destination address is received. A network address translation with port address translation is performed, if the first data is in an IPv4 protocol. A network address translation protocol translation with port address translation is performed, if the first data is in an IPv6 protocol.

Shared port address translation on a router behaving as NAT & NAT-PT gateway

Disclosed are methods and apparatus for performing network address translation (NAT) in a fully connected mesh with NAT virtual interface (NVI). In general terms, mechanisms (e.g., within a combination router/NAT device) are provided for translating network addresses of traffic going between two private domains or realms. These mechanisms may also be used to translate traffic going between a private and public domain. When a particular private address is translated into a public address, a binding is formed between the pre-translation address, the post-translation address, and the interface associated with the private or public address (e.g., an interface of the router/NAT device). Since bindings of different interfaces are tracked, a private address and its associated particular interface may be associated with a particular public address. Accordingly, the translation mechanisms of the present invention may be applied to two duplicate private addresses from two different private domains because the two identical private addresses are distinguished based on their different interfaces.

Apparatus and methods for performing network address translation (NAT) in a fully connected mesh with NAT virtual interface (NVI)

A method for providing handling of data sent between a first network and at least a second network and a third network, wherein the first network is of a first protocol and the at least second and third networks are of a second protocol at least partially overlap is provided. A packet transmitted from the first network is received. The packet has a first address prefix if the packet is directed to the second network and has a second address prefix if the packet is directed to the third network. A destination address of the packet and a source address of the packet are translated from the first protocol to the second protocol. The packet is directed to the second network if the packet has the first address prefix. The packet is directed to the third network if the packet has the second address prefix.

Method and apparatus for providing IPv6 networks to communicate with overlapping IPv4 networks using NAT-PT

Disclosed are methods and apparatus for handling data containing embedded addresses. In general terms, prior to transmission of data having an embedded address or port, an initiating host sends a NAT Probe to an end-host with which the initiating host wishes to communicate. The NAT Probe includes the embedded address or port and a type indicating that translation of the address and/or port is requested if needed. As the NAT Probe traverses through one or more NAT devices as it is transmitted to the end-host, each NAT device is enabled to recognize the NAT Probe type and translate the embedded address and/or port, depending upon the individual NAT device's configuration. When the NAT Probe reaches the final hop NAT device or end-host, a NAT Probe Reply is sent back to the initiating host. The NAT Probe Reply contains a translated embedded address and/or port which is compatible with the end-host's network. The NAT Probe Reply also contains a type which differs from the type of the NAT Probe. As the NAT Probe Reply traverses back through the same NAT devices, the NAT device recognize the type of the NAT Probe Reply and do not translate the embedded address and/or port. The initiating host may then use the translated embedded address and/or port for subsequent communication with the end-host. That is, the initiating host sends data having the translated embedded address and/or port to the end-host. Since the translated address and/port is compatible with the end-host's network, the NAT devices through which the data passes do not have to inspect the payload of the data to handle or translate the embedded address and/or port.

Growing community of inventors

Cary, NC, United States of America

Senthil M Sivakumar