Fortinet, Inc.

Gregory Lockwood

Rajesh I Balay

Girish Bhat

Rama Krishnam Nagarajan

Rama Krishnan Nagarajan

Zahid S Hussain

Tim Millet

Naveed Alam

Joseph Cheng

Samir Jain

Ram Nagarajan

Methods, apparatus and data structures are provided for managing multicast IP flows. According to one embodiment, a router identifies active multicast IP sessions. A data structure is maintained by the router that contains information regarding the active multicast IP sessions and includes multiple pairs of a source field and a group field ({S, G} pairs), a first pointer associated with each of the {S,G} pairs and a set of slots. Each of the {S, G} pairs defines an active multicast IP session. The source field defines a source of a multicast transmission of the multicast IP session and the group field defines a group corresponding to the multicast IP session. The first pointer points to a dynamically allocated set of outbound interface (OIF) blocks. Each slot has stored therein a second pointer to a transmit control block (TCB) data structure that services users participating in the multicast IP session.

Scalable IP-services enabled multicast forwarding with efficient resource utilization

Methods, apparatus and data structures are provided for managing multicast IP flows. According to one embodiment, a network switch module includes a memory and multiple processors partitioned among multiple virtual routers (VRs). Each VR maintains a data structure containing therein information regarding the multicast sessions, including a first value for each of the multicast sessions, at least one chain of one or more blocks of second values and one or more transmit control blocks (TCBs). Each first value is indicative of a chain of one or more blocks of second values. Each second value corresponds to an outbound interface (OIF) participating in the multicast session and identifies a number of times packets associated with the multicast session are to be replicated. The TCBs have stored therein control information to process or route packets. Each second value is indicative of a TCB that identifies an OIF of the network device through which packets are to be transmitted.

Methods, apparatus and data structures are provided for managing multicast IP flows. According to one embodiment, active multicast IP sessions are identified by a network device. A data structure is maintained by the network device and contains therein information regarding the multicast sessions, including a first value for each of the multicast sessions, at least one chain of one or more blocks of second values and one or more transmit control blocks (TCBs). Each first value is indicative of a chain of one or more blocks of second values. Each second value corresponds to an outbound interface (OIF) participating in the multicast session and identifies a number of times packets associated with the multicast session are to be replicated. The TCBs have stored therein control information to process or route packets. Each second value is indicative of a TCB that identifies an OIF of the network device through which packets are to be transmitted.

Methods, apparatus and data structures are provided for managing multicast IP flows. According to one embodiment, active multicast IP sessions are identified by a router. A data structure is maintained by the router and contains therein information regarding the multicast sessions, including a first pointer for each of the multicast sessions, at least one chain of one or more blocks of second pointers and one or more transmit control blocks (TCBs). Each first pointer points to a chain of one or more blocks of second pointers. Each second pointer corresponds to an outbound interface (OIF) participating in the multicast session and identifies a number of times packets associated with the multicast session are to be replicated. The TCBs have stored therein control information to process or route packets. Each second pointer points to a TCB that identifies an OIF of the router through which packets are to be transmitted.

Methods, apparatus and data structures are provided for managing multicast IP flows. According to one embodiment, a network switch module includes a memory and multiple processors partitioned among multiple virtual routers (VRs). Each VR maintains a data structure including information relating to multicast sessions handled by the VR and including a first pointer for each multicast session, a chain of blocks of second pointers and one or more TCBs. Each first pointer points to a chain of blocks of second pointers. Each second pointer corresponds to an OIF of the VR participating in the multicast session defined by the first pointer and defines how many times to replicate packets associated with the multicast session. The TCBs store control information relevant to processing or routing packets. Each second pointer points to a TCB, which identifies the OIF out which packets of the multicast session are transmitted from the VR.

Methods and apparatus are provided for managing multicast Internet Protocol (IP) flows. According to one embodiment, a multicast IP flow is identified at an interface of a network device using information from a packet header. For any newly identified multicast IP flow, if flow-specific services are required, a new first transmit control block (TCB), which includes one or more attributes relating to flow-specific services required by the newly identified multicast IP flow, is created for the newly identified multicast IP flow. Otherwise, if flow-specific services are not required by the newly identified multicast IP flow, a default second TCB, which excludes any attributes relating to flow-specific services and which includes one or more attributes related to a virtual interface (VI) serving as an outbound interface (OIF) for the newly identified multicast IP flow, is used.

Methods, apparatus and data structures are provided for managing multicast IP flows. According to one embodiment, a memory of a router has stored therein a data structure, which includes information relating to multicast sessions being handled by the router and including a first pointer for each multicast session, at least one chain of blocks of second pointers and one or more TCBs. Each first pointer points to a chain of blocks of second pointers. Each second pointer corresponds to an OIF of the router participating in the multicast session defined by the first pointer and defines how many times packets associated with the multicast session are to be replicated. The TCBs are configured to store control information relevant to processing or routing packets. Each second pointer points to a TCB and each TCB identifies the OIF out which packets of the multicast session are transmitted from the router.

This document describes, among other things, a router providing service-enabled multicast forwarding for a flow-based architecture. Services are enabled using inbound/outbound policies from Access Control Lists (ACLs). In a first mode, per-flow services are not enabled, and flows are aggregated for efficiency. In a second mode, per-flow services are enabled, and control information for an outbound interface (OIF) is shared across all multicast flows that do not have per-flow service enabled. A flow management scheme for these modes allows dynamic multicast membership updates while reducing disruption of active flows. This supports a large multicast OIF list and a high rate of multicast 'Joins' and 'Leaves'. This provides scalability and performance, such as desired for deploying multicast for broadband subscriber applications.

A method for routing packets in a router includes establishing a flow data structure identifying a packet flow through a virtual router in the router. Next, a system executing the method receives a packet, said packet having at least one packet header. The method then compares a subset of the at least one packet header to a subset of the flow data structure. If the subset of the at least one packet header matches the subset of the flow data structure, then the packet can be hardware accelerated to a network interface. Otherwise, the packet can be either dropped, or forwarded to a general purpose processor for processing.

Growing community of inventors

Redwood City, CA, United States of America

Gregory Lockwood