Cisco Technology, Inc.

M Frans Kaashoek

James O'Toole

Kirk Johnson

Gang Lu

Barbara Liskov

John J Jannotti

Content servers are directed to send messages to network nodes which are used to obtain IP addresses and to receive responses from the network nodes. The responses provide network service information. The content servers collect data based on the responses and feed the data to a routing server. Based on the data fed to the routing server, respective choices of content servers are selected and provided to the network nodes to respond to clients requesting content server addresses from the network nodes.

Content server selection for accessing content in a content distribution network

In one embodiment, a subnet mask is automatically determined by a first network node attached to a subnet in a packet communication network. The first network node issues plural communication packets from plural source addresses to at least one address known to be used in the subnet to evoke responses, and based on the presence or absence of responses from the network nodes at the known addresses, the first network node determines the subnet mask which represents the subnet.

Method and apparatus for determining a subnet mask based on presence or absence of responses to plural communication packets issued during a search iteration

In one embodiment, a first network node in a subnet retrieves a network configuration from a second network node located outside the subnet. The first network node communicates with at least one other network node to collect information from inter-node communication packets containing network address information other than an address assignment to the first network node. The first network node determines an available network address based on the network address information contained in the collected inter-node communication packets. The first network node is assigned the available network address and locates a network address for at least one subnet router. The network node accesses the second network node located outside the subnet, using the located network address for the at least one subnet router, for an available network configuration from a list of network configurations. The first network node is assigned the available network configuration.

Method and apparatus for retrieving network configuration from a remote network node

A system and method of routing requests received from client computers. The client computer processor is redirected to a router for which the address is within the preferred coverage zone. If a router is not identified for which the address is within a preferred coverage zone, but a router other than the router that received the request is identified for which the address is within a regular coverage zone, the processor is redirected to the router for which the address is within the regular coverage zone. If a message is transmitted from a router behind a firewall to a router outside the firewall, and then a request for data is received from a processor behind the firewall, the processor is redirected to the address of the router. Routers register themselves dynamically into a hierarchy. In another alternative embodiment, a service request from a particular client computer is serviced immediately by the root router rather than redirected to another router. The root router then attempts to find the best source server for the client computer. The next service request from the client computer is dispatched directly by the root router to this best router.

Registration of routers in a hierarchy of routers

The present invention may be used for determining a topology of a network in the presence of network address translation. From an active client behind a translating device, communications are initiated that effect the network address translation. The communications are monitored beyond the translating device to infer partitioning of servers into equivalence sets relative to the network topology induced by the network address translation. Active clients behind the translating device may include a respective actual sending address in a message sent to a server beyond the translating device. The server beyond the translating device distinguishes between communications affected by and not affected by network address translation, which may include comparing an apparent source address of a message against an actual address provided in the message by the active client behind the translation device. The external server may also distinguish between active and passive client messages. The server server may cause a message to a passive client to be redirected to an active client; the active client, in turn, communicates to the external server. The external server stores addresses of devices in translated address sets, which may be maintained in a database and managed in a database manager.

Method and apparatus for determining a network topology in the presence of network address translation

The present invention includes a method and apparatus for automatically assigning a network address to a network device in an electronic communications network carrying inter-device communication packets to and from electronic devices located at assigned network addresses. The network device, also referred to as an appliance, communicates with at least one other network device to collect information from inter-device communication packets, which contain network address assignment information. From the network address assignment information in the communication packets, the appliance determines an available network address. The appliance assumes the available network address. The appliance may access a remote network device to retrieve an available, permanent, network configuration, including IP address.

Method and apparatus for automatic network address assignment

Methods and apparatus for routing requests in a network

A network appliance is capable of remote booting and obtaining its configuration information from a source located far away. The network appliance can be shipped to a business location or office environment without requiring a local boot server in that location or environment and without requiring the presence of a person who is familiar with and highly skilled in configuring the appliance. The invention allows for booting and the obtaining of configuration information, and therefore allows for the functioning of the appliance, regardless of whether there is a local server in the local network environment, such as a DHCP server or a boot server, that has been set up and configured to provide to the appliance the booting and configuration information it requires.

Methods and apparatus for remote configuration of an appliance on a network

A network appliance is capable of remote booting and obtaining its configuration information from a source located far away. The network appliance can be shipped to a business location or office environment without requiring a local boot server in that location or environment and without requiring the presence of a person who is familiar with and highly skilled in configuring the appliance. The invention allows for booting and the obtaining of configuration information, and therefore allows for the functioning of the appliance, regardless of whether there is a local server in the local network environment, such as a DHCP server or a boot server, that has been set up and configured to provide to the appliance the booting and configuration information it requires. Self-organizing distributed appliances (SODAs) according to the invention augment the Internet by providing a self-organizing network that efficiently distributes big data items, i.e., data items that cannot be downloaded timely (on demand) over today's networks. One application of self-organizing distributed appliances is the distribution of high-quality video (a half-hour MPEG-1 movies is about one Gbyte). The SODA network alleviates network bottlenecks.

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Lexington, MA, United States of America

M Frans Kaashoek