H3C Technologies H3C S7500E Series Switches - Manual (Page 97)

4-1
4
IPC Configuration
When configuring IPC, go to these sections for information you are interested in:
z IPC Overview
z Enabling IPC Performance Statistics
z Displaying and Maintaining IPC
IPC Overview
Introduction to IPC
Inter-Process Communication (IPC) is a reliable communication mechanism among different nodes.
The following are the basic concepts in IPC.
Node
An IPC node is an entity supporting IPC; it is an independent processing unit. In actual application, an
IPC node corresponds to one CPU.
z One centralized device has only one CPU, therefore corresponding to one node.
z An Intelligent Resilient Framework (IRF) is an interconnection of several centralized devices, with
each member device corresponding to one node. Therefore, an IRF corresponds to multiple
nodes.
z Typically a distributed device is available with multiple boards, each having one CPU, some
boards are available with multiple CPUs. Some distributed devices may be available with multiple
CPUs, for example service CPU and OAM CPU. Therefore, a distributed device corresponds to
multiple nodes.
Therefore, in actual application, IPC is mainly applied on an IRF or distributed device; it provides a
reliable transmission mechanism between different devices and boards.
Link
An IPC link is a connection between any two IPC nodes. There is one and only one link between any
two nodes for packet sending and receiving. 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; a connection is established between them if the handshake succeeds.
The system identifies the link connectivity between two nodes using link status. An IPC node can have
multiple links, each having its own status.
Channel
A channel is a communication interface for 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.
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 Figure 4-1 .