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IPC configuration
IPC overview
Inter-Process Communication (IPC) is a reliable communication mechanism among processing units,
typically CPUs. It is typically used on a distributed device or in an IRF fabric to provide reliable inter-card
or inter-device transmission. The following are the basic IPC concepts.
Node
An IPC node is an independent IPC-capable processing unit, typically, a CPU. Typically, distributed
devices and IRF fabrics have multiple IPC nodes, because each card or device in them has at least one
CPU.
Link
An IPC link is a connection between any two IPC nodes. There is one and only one link for packet
sending and receiving between any two nodes. All IPC nodes are fully connected.
IPC links are created when the system is initialized: When a node starts up, it sends handshake packets
to other nodes. It the handshake succeeds, a connection is established.
The system uses link status to identify the link connectivity between two nodes. An IPC node can have
multiple links, each having its own status.
Channel
A channel is a communication interface used by an upper layer application module of a node to
communicate with an application module of a peer node. Each node assigns a locally unique channel
number to each upper layer application module to identify this module.
Data of an upper layer application module is sent to the IPC module through a channel, and the IPC
module sends the data to a peer node through the link. The relationship between a node, link and
channel is as shown in