Abstract: A method of controlling communication between a head-end system and a number of client systems through a network, wherein, for each receiver, only a nearest one of the multicast router systems in the network is configured to forward a copy of a message addressed to the multicast groups of which the receiver is a member directly to the receiver, includes: maintaining subscriber group information linking each registered one of the number of client systems to an associated one of a plurality of subscriber groups, and allocating registered client systems to at least one multicast group, such that all client systems associated with a particular subscriber group are in a common multicast group. Information uniquely identifying the nearest multicast router system nearest to a receiver for a first client system is obtained, and the first client system is assigned to a subscriber group including at least one further client system having the same nearest multicast router system.

Abstract: A media transfer system includes a media transfer messaging application stored on a central server to be downloaded by a plurality of client devices and stored thereon. The plurality of client devices are communication with a network. The plurality of client devices having the media transfer messaging application stored thereon are enabled to transmit media between one another via the network and are defined as a receiving client device when receiving media and a sending client device when sending media. The sending client device is authenticated prior to sending media to be defined as an authenticated sending client device, and media sent from the sending client device is received by the receiving client device as a message. The receiving client device is adapted to accept, reject or delay delivery of the message, and is adapted to send a message received from a sending client device to at least one receiving client device.

Abstract: A record medium on which a load distribution program capable of dynamically determining a service providing server which can provide a service of high quality according to a place where a client is installed is recorded. A delay time determination section analyzes a request sent from a client, identifies a position on a network of the client, and determines processing delay time the client takes to receive a response from each data center on the basis of a communication path between the position of the client and a position on the network of each data center. An allocation determination section preferentially selects a data center which can provide a service to the client after shortest processing delay time as a recommended data center on the basis of the processing delay time determined by the delay time determination section. A service allocation section makes a server in the recommended data center provide the service to the client which outputted the request.

Abstract: A channel merging method for a VOD system, said method comprises the steps of: in response to requests from a plurality of clients for a video program, establishing a root channel (S1) and at least one sub-channel (S11), said root channel (S1) being established according to a request from a client that makes the earliest request, each of said sub-channels (S11) being established in response to a request from a client that makes a later request; and monitoring variation of the number of the clients that are using each of said established channels, and maintaining the channel if the number of the clients using the monitored channel is not zero, and closing the channel if the number of the clients using the monitored channel becomes zero.

Abstract: The invention relates to the selection of devices of a wireless network, particularly wireless home control networks, for example lighting control networks in buildings. It is an object of the invention to provide an improved method and System to select devices of a wireless network, particularly a network of wireless lighting devices. According to the invention, for selecting a certain device in the wireless network a broadcast message is sent out by a wireless remote device (S1O). Only devices with a certain communication link quality respond with unicast messages (S20). The wireless remote device then sends a command to the device with best communication link quality for selecting this device. This enables a user to select devices without buttons in a wireless network.

Abstract: A data distribution system and method are described herein to improve the distribution of market information to subscribing client devices. Market information updates are provided to subscribing devices over a communication link every time a change in the market occurs. If a bandwidth limitation is reached on the communication link, the preferred embodiments switch to a second mode of transmission such that the market information updates are provided only at predetermined intervals. The preferred embodiment monitors the bandwidth consumption to determine what mode of transmission to apply, and in response, it can dynamically change between modes of transmission. By dynamically adjusting the mode of transmission to comport with the current network bandwidth, the preferred embodiments may provide a network friendly, data intensive, and fast response market information feed.

Abstract: A network system (10). The system comprises a plurality of nodes (PE, CE). Each node in the plurality of nodes is coupled to communicate with at least one other node in the plurality of nodes. Further, each node in the plurality of nodes is coupled to communicate to another node via a respective primary path and via a respective backup path. Still further, each node in the plurality of nodes is operable to perform the steps of, when receiving network traffic as a receiving node, detecting delay (110, 120; 130, 140; 160, 170) in traffic received from a transmitting node, and, in response to detecting delay, communicating a signal to the transmitting node. In response to the signal, the transmitting node is operable to dynamically adjust (150; 190) a distribution of traffic through a respective primary path and a respective backup path from the transmitting node to the receiving node.

Abstract: An electronic system in which integrated circuits employing cornered I/O are arranged in a framework including an optional path manager and at least one updateable routing table. Packet routing options are described with solutions being provided to minimize transmission latency and pathway alternatives.

Abstract: Proposed are a storage system, a path management method and a path management device capable of ensuring the processing performance demanded by a user while seeking to improve the access performance from a host system to a storage apparatus. Path switching control for dynamically switching the path to be used by the host system according to the loaded condition of the respective paths between the host system and the storage apparatus is executed; and a path is selected as needed according to a policy containing path switching rules created by a user, and path switching control for excluding the selected path from the target and dynamically switching the path to be used by the host system is executed.

Abstract: A system and method for improving content diversification in data driven streaming includes computing a weight factor and a qualification factor for each of at least two nodes among a plurality of nodes, based upon a bandwidth of each node. Content is pushed to a node based on the qualification factor and the weight factor of each node. The qualification factor is updated for the node which received pushed content.

Abstract: DNS name resolution is integrated into each node in a network storage cluster, to allow load balancing of network addresses, using a weighted random distribution to resolve DNS requests. A node in the cluster gathers statistics on utilization of resources, such as CPU utilization and throughput, on nodes in the cluster and distributes those statistics to all other nodes. Each node uses the same algorithm to generate weights for the various IP addresses of the cluster, based on the statistics distributed to it. The weights are used to generate a weighted list of available network addresses. In response to a DNS request, a DNS in a given node randomly indexes into the weighted address list to resolve requests to a network address. The weights are chosen so that the DNS is likely to pick an IP address which has a low load, to balance port and node usage over time.

Abstract: 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.

Abstract: There is provided a method (700, 900) of selecting nodes (120, 130, 140) in a communication network (100), in which a source node (110) communicates with destination nodes (120, 130, 140). The method (700, 900) includes steps of: (a) transmitting a first message (770, 950) from the source node (100) to the destination nodes (120, 130, 140); (b) receiving response messages (780, 960, 980, 990) at the source node (110) from one or more of the destination nodes (120, 130, 140); (c) in an event of contention arising between the response messages (780, 960, 980, 990) received at the source node (110), iteratively selecting a sub-set (510, 520, 610, 620) of the destination nodes (120, 130, 140) to resend their response messages for receipt at the source node (110) until the response messages are received at the source node (110) without contention, the response messages received without contention being indicative of a suitable destination node having been selected.

Abstract: The present invention provides a system and method for optimizing delivery of a content item from a content distribution network to a display device, where the content distribution network includes transcoding resources to convert the content item from a first format to a second format. A computing device receives a request to deliver the content item to the display device. The system selects, from the transcoding resources, an optimized transcoding resource based on an evaluation of metadata that describes the content item, a preferred technique for transcoding the content item, a state of the content distribution network, a predicted behavior for the user, and metadata that describes the display device. The system reserves the selected transcoding resource, and delivers the content item to the display device on a media stream that utilizes the selected transcoding resource.

Abstract: A method and apparatus for composite link assignment are provided such that network capacity is sufficient to handle all the traffic (e.g., load) while an objective function, e.g., the total cost of the capacity is minimized. The present method receives a plurality of weights for a plurality of arcs and a load for the network. An objective function is selected for minimization, where the present method then determines the composite link assignment to handle the load while the objective function is minimized. In one embodiment, the composite link assignment comprises a plurality of different link types for the plurality of arcs.

Abstract: A method relates to routing data in a network, between source nodes and destination nodes pertaining respectively to distinct source groups and destination groups. The network includes intermediate groups forming at least two potential data transmission paths through which the data can be transmitted. The method includes a determination step, for each group of nodes of the network, including feedback by the nodes of the information group for determination of a quality level, representing quality of the data transmission through this group, and a step of selecting at least one transmission path from among the potential paths, for the transmission of data between the source nodes and destination nodes through the selected transmission path. The selection is made based on the quality levels of the intermediate groups of the network.

Abstract: Disclosed is a technique for data synchronization. A first identifier for a portion of data on a primary volume is determined, wherein a unique identifier is associated with each portion of data at the primary volume. A second identifier for a portion of corresponding data at a secondary volume is determined, wherein a unique identifier is associated with each portion of data at the secondary volume. The first and second identifiers are compared. When the first and second identifiers do not match, the portion of corresponding data at the secondary volume in a storage device is replaced with the portion of data at the primary volume.

Abstract: A packet compressor 12 operates under a reliable mode or an optimistic mode. A mode determination unit 31 counts the number of ACK packets or NACK packets received by a unit time X by an ACK/NACK packet receiver 14. When the counted number of NACK packets is larger than a predetermined value Y, the mode determination unit 31 switches the operation mode of the packet compressor 12 to the reliable mode. When the counted number of ACK packets is larger than a predetermined value Z, the mode determination unit 31 switches the operation mode of the packet compressor 12 to the optimistic mode.

Abstract: The present invention comprises methods for increasing the rank of the routing matrix of an IP network by systematically altering link weights in the IP network. A full rank routing matrix may be used with further methods in accordance with the present invention to estimate the mean traffic of the IP network based upon the full rank routing matrix and measured link utilization values. The mean traffic and the covariance of the traffic may be iteratively estimated until the estimates coverage. Example methods in accordance with the present invention for estimating mean traffic and covariance of traffic are described for both stationary and non-stationary link utilization data.

Abstract: A streaming operator assignment system and method for determining a streaming operator assignment that minimizes overload in a data processing system. Embodiments of the streaming operator assignment system include an optimization goals definition module, which defines optimization goals in terms of fundamental quantities that system administrators and application writers want to control, such as minimizing the worst case latency over all periods of time, or minimizing how much the system is backlogged with work. Embodiments of the streaming operator assignment system also include an optimization goals solution module that optimizes and solves a selected optimization goal. A specialized optimization technique is used to find the best operator (or load) assignment using the optimization goals to measure of the value of the assignment.

Abstract: A soft notification technique isolates address family application based errors or events occurring within a routing protocol, such as the Border Gateway Protocol (BGP), used to exchange routing information between a router and its peer router over a BGP session operating on a reliable transport. The technique apportions the session into a plurality of logical subsets, each of which is associated with an address family application (AFI/SAFI) module of a BGP protocol executing on the routers. BGP soft notification messaging is employed to allow the router to notify its peer of an isolated error condition or event associated with an AFI/SAFI module. Isolation of the error/event enables restart (“soft reset”) of only the associated AFI/SAFI module, thereby obviating the need to reset or terminate the entire BGP session and reliable transport between the router and peer. Notably, soft reset of the module occurs without disrupting services provided by other AFI/SAFI modules of the BGP protocol.

Abstract: A method and system for provisioning circuits on multiple parallel links with a single setup message is disclosed. A setup message specifying links in a circuit path is transmitted to switches along the circuit path. If a switch determines that a link specified in the setup message has insufficient bandwidth for the circuit, the switch substitutes a parallel link having sufficient bandwidth for the specified link in the circuit path. The setup message can indicate whether substitution for a link is permitted. This can be used to prevent substitution for links when provisioning service routes for new circuits in order to maintain diversity requirements, while allowing substitution for links when provisioning restoration routes for failed circuits in order to reduce restoration time.

Abstract: Systems and methods for transmitting data across a firewall are described. A representative method includes: receiving a request to transmit data to a destination; searching for a firewall associated with the destination, the firewall being configured to prohibit communication to the destination via a primary communication protocol and allow communication to the destination via a secondary communication protocol. If the firewall is detected, automatically configuring the data for communication with the secondary communication protocol; and transmitting the data to the destination by utilizing the secondary communication protocol. Other devices and programs are disclosed.

Abstract: An apparatus is for setting a communication path between a communication terminal device connected through a first network and a plurality of second networks. The apparatus includes a name resolution request generator, a destination determiner, and a path setting unit. The name resolution request generator generates and transmits a name resolution request addressed to a name resolution server of the second networks, based on a name resolution request for name resolution of a destination received from the communication terminal device. The destination determiner assigns a priority to a name resolution response received from the name resolution server, and determines a destination based on the priority. The path setting unit sets a path by generating a routing table from path information including address information of the destination, address information of a gateway of the second networks, and an interface name.

Abstract: A wireless communications apparatus used in a wireless communications network consisting of multiple wireless communications apparatuses mutually connected via wireless links includes (a) a buffer configured to temporarily store information received from an adjacent wireless communications apparatus or a user terminal located under the wireless communications apparatus; (b) a routing control information processing unit that estimates a node cost representing traffic at the wireless communications apparatus and a link cost representing a radio condition of the link to determine a transmission route based on cost information reflecting both the node cost and the link cost; and (c) a routing control unit that designates a next hop to which information accumulated in the buffer is to be transmitted according to the determined transmission route.

Abstract: The invention provides an enforcement mechanism for limiting the propagation of content to a predefined proximity in a heterogeneous network. The protection mechanism determines the distance associated with wireless links of the heterogeneous networks and verifies that the distance is within the predefined proximity limits. The distance may be measured by evaluating the signal strength of received signals. The protection mechanism further uses round trip time determinations to enforce the proximity limits on wired or unknown segments of the heterogeneous network. Specifically, the round trip time associated with a wired or unknown segment may be determined using the round trip time associated with the wireless segments and the total round trip time of the network as a whole. The round trip time of the wired or unknown segment is then compared to a round trip time limit associated with the proximity requirement for distributing content.

Abstract: A wireless networking system uses mobile and fixed transceivers to achieve a network with changing topology. A routing process includes quality-of-service considerations in the network to allow for features such as file or other data transfer, streaming audio and video, digital telephone communications, etc. The routing process adapts to transceiver units entering, leaving, or moving within, the network. Auxiliary networks such as the Internet, campus or corporate intranets, home networks, etc., can be accessed through the wireless network. Features, designs and user interfaces for the units are described. Security and access control of media content and other data is presented.

Abstract: A Fiber Channel switch is presented that tracks the congestion status of destination ports in an XOFF mask at each input. A mapping is maintained between virtual channels on an ISL and the destination ports to allow changes in the XOFF mask to trigger a primitive to an upstream port that provides virtual channel flow control. The XOFF mask is also used to avoid sending frames to a congested port. Instead, these frames are stored on a single deferred queue and later processed in a manner designed to maintain frame ordering. A routing system is provided that applies multiple routing rules in parallel to perform line speed routing. The preferred switch fabric is cell based, with techniques used to manage path maintenance for variable length frames and to adapt to varying transmission rates in the system. Finally, the switch allows data and microprocessor communication to share the same crossbar network.

Abstract: A method, apparatus, system, and signal-bearing medium that, in an embodiment, accumulate multiple work units into a bundle and send the bundle to a selected active server. The active server is selected based on the relative costs for the work units and costs for servers. In an embodiment, selecting the active server includes determining relative work unit costs and relative server costs, calculating total weighted costs for the servers based on the relative work unit costs and the relative server costs, and selecting the active server that has the lowest total weighted cost. The active server may either process a work in the bundle locally or send the work unit to a passive server for processing. The active server determines whether each work unit can be executed at the active server. If the work unit can be executed on the active server, the active server executes the work unit and creates local results.

Abstract: Registering a client with a distributed service. A method may be practiced, for example, in a network computing environment including a client at a local site and a number of distributed services at a number of remote sites. The method includes pinging one or more distributed services at one or more remote sites. A message is received from a distributed service from among the one or more distributed services. The message specifies an optimal remote site. The method further includes registering with a distributed service at the optimal remote site.

Abstract: The present invention routes an application request to at least one of a plurality of sites in a packet data network. Session Initiation Protocol (SIP) messages that establish initial dialogs and SIP messages that are stand-alone requests are sent from a call session control function system to a SIP application load distribution system. The SIP application load distribution system routes a SIP message to at least one destination site, based at least in part on user-defined local state data and a user-defined application load distribution policy. Local state data is sent from a plurality of sites to an application management and health checking system. Local state data may be sent autonomously from the plurality of sites. Local state data may also be sent from the plurality of sites in response to a request issued by the application management and health checking system.

Abstract: Method, system and computer usable program code for dynamic component placement in an event processing system having producers, consumers, a plurality of nodes between the producers and the consumers, and a flow graph representing computational components to be executed between the producers and the consumers. A description of a change to the system is received. At each node, next-hop neighbor nodes for each consumer are identified. A routing value is assigned to each next-hop neighbor node for each consumer. Using the routing values in a context of the change, a performance cost of the system is estimated based on hypothetical changed placements of the computational components at nodes along paths from a producer to a consumer through the next-hop neighbor nodes for each consumer, and a changed placement of the computational components that minimizes performance cost of the system relative to the hypothetical changed placements is selected.

Abstract: A telecommunications system includes an MPLS network. The system includes a source node in communication with the network. The system includes a destination node in communication with the network and with the source node through a plurality of different paths. Each path of which has a residual bandwidth at a given time. The source node forming a connection with the destination node at the given time across the path of the different paths as a function of residual bandwidth. A method for selecting a preferred LSP path from a set of equal cost paths. A method for sending packets in a telecommunications network. A software program for a management station or a switch.

Abstract: Determining a path for network traffic between a source compute node and a destination compute node in a parallel computer including identifying a group of compute nodes, the group of compute nodes having topological network locations included in a predefined topological shape; selecting, from the predefined topological shape, in dependence upon a global contention counter stored on the source compute node, a path on which to send a data communications message from the source compute node to the destination compute node; and sending, by the messaging module of the source compute node, the data communications message along the selected path for network traffic between the source and destination compute nodes.

Abstract: Determining a path for network traffic between a source compute node and a destination compute node in a parallel computer including: beginning with an identified group of compute nodes that includes the source compute node and iteratively until an identified group of compute nodes includes the destination compute node: identifying a group of compute nodes, the group of compute nodes having topological network locations included in a predefined topological shape; selecting a path for network traffic between compute nodes having topological network locations included in the predefined topological shape, and when an identified group of compute nodes includes the destination compute node: selecting a final path for network traffic; and sending a data communications message along the path for network traffic between the source compute node and the destination compute node, the path including, in order of selection, the selected paths and the selected final path.

Abstract: Systems and methods to implement load balancing of connections to a server computer in a server collection are described. The server collection receives connection requests from remote clients over a network. A session broker evaluates one or more load parameters of the server computers in the server collection and, based on those load parameters, determines load associated with each server computer. The session broker redirects the connection requests to the server computer which has a lesser load.

Abstract: A communication system is disclosed comprising a communication network and a communication device. The communication device reads machine-readable information from a card, wherein the information on the card corresponds to data hosted by a content provider in the communication network. The communication device processes the information to locate the content provider, and transmits a request for the data and the information to the communication network. The communication network processes the information to translate the data hosted by the content provider to a format suitable for the communication device. The communication network also processes the information to handle a financial transaction for the data.

Abstract: A method and apparatus for updating a shortest path graph or a shortest path tree are disclosed. For example, an arc weight is changed for an arc in the network, where a plurality of affected nodes in the network is determined. The distance of each of the affected nodes is determined, where a subset of the plurality of affected nodes is then placed in a heap. One aspect of the present invention is that not all the affected nodes are placed in the heap. In one embodiment, the present reduced heap approach only applies the Dijkstra's algorithm to those affected nodes whose distances change in a smaller amount that the change in the arc weight. In turn, the shortest path graph or the shortest path tree is updated in accordance with the affected nodes placed in the heap.

Abstract: In one embodiment, a first request is received for a probe link from a client that has downloaded a page. The request is received from an application. A test may be performed to determine a server that could optimally service a content request from the client. After receiving the request, the content router sends a re-direct to the client where the re-direct causes the client to follow the re-direct to the server. The server then sends a re-direct back to the client, which the client follows by sending a second request to the content router. The second request is associated with the client and the round-trip time is calculated for the server. It is then determined if the location for the server should be designated as the content deliverer to the client based on the calculated round-trip time.

Abstract: A method and system are disclosed for creating portfolios of requests so as to reduce or minimize the variance in the workloads generated by those requests. The invention also takes into account the throughput of the servers that are servicing the requests. In a preferred embodiment, the method comprises the steps of establishing a set of system parameters; using said parameters to generate a model, said model including a defined optimization problem; and solving said optimization problem to output a set of mixing weights. The set of parameters and said mixing weights are used to generate a task; and the service requests are distributed to different service teams according to the generated task. Also, for example, the distributing may be done by distributing requests of type i to team j with weight proportional to wij.

Abstract: A data streaming system comprises: one or more streaming sources, one or more streaming clients, a network connecting said streaming sources and said clients, and a level of service selector able for each data stream to monitor the network, the respective streaming source and the respective streaming client to control streaming to the respective streaming client to define a level of service of the data stream. For a video stream the level of service may define the frame rate, the resolution, the overall quality or a level of masking used.

Abstract: A method, a system, an apparatus, and a computer program product are presented for a fragment caching methodology. Within the request path from a client to a server, a first computing device may attach to a request message a message header that indicates that the first computing device supports fragment processing; a second computing device within the request path processes this request message. When the second computing device receives a response message corresponding to the request message, it can check for a message header directive that indicates that it should cache the response message's fragment only if the response path does not have at least one computing device that supports the processing of fragments; if so, then it forwards the response message without caching its contained fragment.

Abstract: Disclosed are a method and system for establishing a session, via the Internet, between a user and an application. The method comprises the steps of providing a plurality of instances of the application, each of the instances having a respective Internet address; and the user accessing one of said instances, via the Internet, by means of the Internet address of said one instance. That accessed one instance selects one of the instances, according to a defined procedure, for a session with the user, and sends to the user an identifier, such as an URL, for accessing said selected one instance. The user accesses the selected one instance, via the Internet, by using said identifier.

Abstract: In a network, a user can configure host-level policies usable for load balancing traffic to servers of a domain. A global server load balancing (GSLB) switch provides load balancing to the servers, and is configured with the GSLB host-level policies. Users can define a host-level policy (alternatively or additionally to a globally applied GSLB policy) and apply the host-level policy to hosts in domains configured on the GSLB switch. Thus, the user can enable different policies for different hosts. This allows the user to have the flexibility to control metrics used for selection of a best address for querying clients, as well as the metric order and additional parameters used in the GSLB process, at the host level.

Abstract: A flexible mechanism and method for routers to select the egress point for each destination comprises identifying a plurality of points of egress from an autonomous system, ranking the plurality of points of egress according to a metric having variable and fixed terms, selecting a point of egress having the smallest rank, and transmitting packets from a point of ingress via a path to the selected point of egress. The metric is across a plurality of destinations and respective possible points of egress from the autonomous system and the metric is m(i, p, e) equaling ?(i, p, e)·d(G,i,e)+?(i, p, e) where a and ? are configurable values, i is the identity of the router, p is the destination, G is an undirected weighted graph, the d function is the interior gateway protocol distance and e is a point of egress.

Abstract: A system and method for sending long distance telephone calls over the Internet utilizes cost and quality of service data to optimize system performance and to minimize the cost of completing the calls. The system utilizes a network of gateways connected to the Internet. The gateways receive calls from various service providers and convert the analog calls into data packets which are then placed onto the Internet. Similarly, the gateways take data packets off the Internet, convert the data packets back into analog format, and provide the analog telephone calls to the same or another service provider. The system periodically checks the quality of communications between each of the gateways, and uses this information, in combination with cost information, to determine how to route the calls over the Internet. Special addressing protocols can be used by a system embodying the invention to reduce or eliminate unnecessary signaling between gateways as call setup procedures are carried out.

Abstract: A computer system and computer program product for optimizing an aspect of an Information Technology (IT) structure of an IT system. The aspect of the IT structure is optimized with respect to at least one control parameter. The IT structure includes a plurality of elements. Each element independently is a hardware element, a software element, or a combination of a hardware element and a software element. Each control parameter has a value that is specific to each element of the IT structure.

Abstract: The invention relates to methods for selection of packet transmission routes between two network sites in a case, in which the sites are connected to the rest of the network via a plurality of connections each. According to the invention, the source network site is arranged to select which connection is used at the source end and which connection is used at the destination end, and base the selections at least partly on the basis of a round trip time value and a packet success rate value. The selection criteria can advantageously be time dependent.

Abstract: Methods, systems, and computer program products for multipath Shortest-Path-First (SPF) computations and distance-based interface selection for VoIP traffic are disclosed. According to one method, a multi-path router instance associated with a plurality of network interfaces in a source IP device is provided. A cost is assigned to each of a plurality of internal segments between the multi-path router instance and the network interfaces associated with the multi-path router instance. An aggregate cost is calculated for each of a plurality of traffic paths originating at the multi-path router instance in the source IP device and extending through each of the network interfaces associated with the multi-path router instance to a destination IP device in the network. A list of IP paths is generated, and the paths in the list are ranked based on the calculated cost. Traffic is sent from the source IP device over at least one of the paths in the list.

Abstract: Provided is a computer system which includes computers and a storage system coupled to the computers. The storage system includes a first load measuring module that measures a first access load for each channel adaptor. At least one of the computers includes a path management module that manages paths through which the computers access logical units. The path management module includes a second load measuring module that measures a second access load imposed by access from the computer to the logical unit, and an active path setting module that selects one of the channel adaptors based on the first access and the second access load measured by the first and second load measuring modules, and setting an active path passing through the channel adaptor. Thus, a load on an entire system is balanced, thereby improving performance while a cache hit rate of a storage system is maintained.