5-3
2) Data
VLAN
A data VLAN is a VLAN dedicated to transferring data packets. Both RRPP ports and non-RRPP
ports can be assigned to a data VLAN.
Node
Each device on an RRPP ring is referred to as a node. The role of a node is configurable. There
are the following node roles:
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Master node: Each ring has one and only one master node. The master node initiates the
polling mechanism and determines the operations to be performed after a change in
topology.
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Transit node: Transit nodes include all the nodes except the master node on the primary
ring and all the nodes on subrings except the master nodes and the nodes where the
primary ring intersects with the subrings. A transit node monitors the state of its
directly-connected RRPP links and notifies the master node of the link state changes, if any.
Based on the link state changes, the master node decides the operations to be performed.
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Edge node: A node residing on both the primary ring and a subring at the same time. An
edge node is a special transit node that serves as a transit node on the primary ring and an
edge node on the subring.
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Assistant-edge node: A node residing on both the primary ring and a subring at the same
time. An assistant-edge node is a special transit node that serves as a transit node on the
primary ring and an assistant-edge node on the subring. This node works in conjunction
with the edge node to detect the integrity of the primary ring and perform loop guard.
As shown in
, Ring 1 is the primary ring and Ring 2 is a subring. Device A is the
master node of Ring 1, Device B, Device C and Device D are the transit nodes of Ring 1. Device
E is the master node of Ring 2, Device B is the edge node of Ring 2, and Device C is the
assistant-edge node of Ring 2.
Primary port and secondary port
Each master node or transit node has two ports connected to an RRPP ring, one serving as the
primary port and the other serving as the secondary port. You can determine the role of a port.
1) In terms of functionality, the difference between the primary port and the secondary port of
a master node is:
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The primary port and the secondary port are designed to play the role of sending and
receiving loop-detect packets respectively.
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When an RRPP ring is in Health state, the secondary port of the master node will logically
deny data VLANs and permit only the packets of the control VLANs.
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When an RRPP ring is in Disconnect state, the secondary port of the master node will
permit data VLANs, that is, forward packets of data VLANs.
2) In terms of functionality, there is no difference between the primary port and the secondary
port of a transit node. Both are designed for transferring protocol packets and data packets
over an RRPP ring.
As shown in
, Device A is the master node of Ring 1. Port 1 and Port 2 are the
primary port and the secondary port of the master node on Ring 1 respectively. Device B,
Device C, and Device D are the transit nodes of Ring 1. Their Port 1 and Port 2 are the primary
port and the secondary port on Ring 1 respectively.