Abstract: In one embodiment, a method comprises transmitting a PING from a network element to a computing device, wherein a static route is between the network element and the computing device. The method also includes causing a distribution of availability of the static route to at least one other network element based on whether the computing device responded to the PING.

Abstract: A machine readable medium for tunneling Ethernet is described. A machine readable medium comprises receiving an Ethernet frame and transmitting the Ethernet frame over a non-homogenous tunnel, the tunnel distinguishing subscriber traffic.

Abstract: A method and apparatus for load balancing and protecting data traffic in an optical ring is described. A method comprises configuring multiple spanning trees in a set of one or more network elements of an optical ring, load balancing with the multiple spanning trees data traffic transmitted in unprotected data channels provisioned through the optical ring, and protecting the unprotected data channels with the multiple spanning trees.

Abstract: A method and apparatus for virtual private networks (VPNs) is described. A computer implemented method comprises determining a set of endpoints for a generic routing encapsulation (GRE) tunnel, determining a key (the key corresponding to a VPN), dynamically establishing the GRE tunnel with the set of endpoints and the key, and processing a set of GRE traffic for the VPN.

Abstract: A method and apparatus for deframing signals is described. In one embodiment of the invention, a computer implemented method comprises receiving a plurality of signals at a first clock rate, synchronizing the plurality of signals to a second clock rate, and deframing the plurality of signals.

Abstract: Methods and apparatuses for providing clientless IP services for subscribers on a network interface that does not require either explicit client subnet configurations or explicit routes from the interface to the client subnets.

Abstract: A network element modifying the DHCP lease timer is described. According to one embodiment, an exemplary method includes maintaining, at a network element, DHCP lease time for one or more clients and in response to a DHCP renewal request from a client, on behalf of a DHCP server, providing DHCP renewal services to the client based on lease time information associated with the client without invoking the DHCP server.

Abstract: A method and apparatus for mesh based protection of an optical network is described. A method comprises protecting a first set of one or more optical sub-channels with automatic protection switching, utilizing a second and third set of one or more optical sub-channels to transmit traffic in accordance with a mesh process to transmit traffic, and transmitting traffic in the third set of optical sub-channels, which would have been transmitted in the second set of optical sub-channels, in accordance with routes determined by the mesh process in response to an alarm indicating a failure affecting the second set of optical sub-channels.

Abstract: Methods and apparatus for rerouting network traffic are described herein. In one embodiment, an example of process includes maintaining as a part of a routing table of a network element information regarding one or more backup links leading to a node using label switched protocols (LSPs), the node being adjacent to the network element, and in response to a failure of a primary link coupling the network element to the node, the network element rerouting network traffic to the node via the one or more backup paths without having to notifying and waiting for a response from a headend node that originates the network traffic. Other methods and apparatuses are also described.

Abstract: A method and apparatus for exception handling in a multi-processor environment are described. In an embodiment, a method for handling a number of exceptions within a processor in a multi-processing system includes receiving an exception within the processor, wherein each processor in the multi-processor system shares a same memory. The method also includes executing a number of instructions at an address within a common interrupt handling vector address space of the same memory. The number of instructions cause the processor to determine an identification of the processor based on a query that is internal to the processor. Additionally, the method includes modifying execution flow of the exception to execute an interrupt handler located within one of a number of different interrupt handling vector address spaces.

Abstract: A method and apparatus for processing out-of-order processing of packets is described. In one embodiment, the method includes receiving a packet, which is in an original position relative to other packets; and attempting, by a primary processing unit, to classify and process the packet. The method also includes determining whether the packet was completely classified and processed by the primary processing unit; and upon determining that the primary processing unit completely classified and processed the packet, bypassing a secondary processing unit. The method also includes transmitting the packet onto a network, the packet being transmitted in its original position relative to the other packets.

Abstract: A method and apparatus for agnostic PPPoE switching is described. A method in a network element comprises converting Point to Point Protocol (PPP) protocol data units (PDUs) encapsulated according to different protocols into PPP PDUs with a uniform encapsulation, and transmitting the uniformly encapsulated PPP PDUs.

Abstract: A method and apparatus for route oscillation reduction is described. A method in a network element comprises advertising to a set of one or more internal peers a best external route if a best overall route is not an external route, wherein external routes are routes communicated from an external peer that is not within the network element's group, wherein said set of internal peers are within the network element's group, and advertising to a set of one or more external peers a best internal route that has been received from an internal peer if the best overall route is not an internal route.

Abstract: A method and apparatus for virtual circuit routes is described. A method in a network element comprises associating a virtual circuit to a layer 3 next hop, the virtual circuit being associated with a layer 2 protocol specific logical circuit, receiving a packet on the logical circuit, processing the packet with configuration information indicated by the virtual circuit, and forwarding the packet to the layer 3 next hop associated with the virtual circuit without processing the packet's layer 3 header.

Abstract: A method an apparatus for multiple contexts and layer 3 virtual private networks is described. A method comprises providing a layer 3 virtual private network (VPN) to a first customer; providing backbone access to a second customer; and maintaining on a single network element a first set of information for the first customer separately from a second set of information for the second customer.

Abstract: A method and apparatus for providing point-to-multipoint label switch paths (LSPs) in a Multi-Protocol Label Switching (MPLS) network is described. In one embodiment, a point-to-multipoint LSP is built in a MPLS network by using Resource Reservation Protocol Traffic Engineering (RSVP-TE) to signal the point-to-multipoint LSP as separate point-to-point LSPs and to merge the separate point-to-point LSPs into the point-to-multipoint LSP.

Abstract: A method and apparatus for the incorporation of any size and location of concatenated SONET frames, which carry packet data, in an SONET signal are described. In an embodiment, a method includes receiving packet data. Additionally, the method includes concatenating the packet data into a Time Division Multiplexing (TDM) Synchronous Optical Network (SONET) signal. The concatenation can be across any locations within the TDM SONET signal, and a size of the concatenation can be in increments of single SONET frames. The method also includes transmitting the TDM SONET signal having the concatenated packet data.

Abstract: A method and apparatus for representing a label switched path. In one embodiment, a computer implemented method comprises representing a label switched path (LSP) with a data structure, the data structure indicating a virtual ingress and an identifier to distinguish the LSP from other LSPs represented with the same virtual ingress.

Abstract: The use of IP address blocks with default interfaces in a router is described herein. According to one embodiment, an exemplary method includes in response to a request for a first IP address received from a first client at an interface of the network element, assigning the first client an IP address from a first block of IP addresses dynamically allocated from an IP address provider separated from a pool of statically preassigned IP addresses, if there is no IP address remained unassigned in the pool of statically preassigned IP addresses, and advertising reachability information in a network with respect to the first block of the IP addresses dynamically allocated from the IP address provider, such that other entities of the network are aware of the first block of the IP addresses. Other methods and apparatuses are also described.

Abstract: Context selection in a network element through subscriber flow switching. According to one embodiment of the invention, authentication, authorization and accounting is performed for a subscriber desiring to connect to a plurality of services on different contexts. In response, bindings are established to a plurality of contexts for the subscriber. In response to receiving a traffic packet from the subscribed, at least certain header information from the traffic packet is accessed. Based on at least the accessed header information, one of the plurality of contexts is selected for that traffic packet.