Difference Between RSTP and PVST (With Table)

The multicast routing protocol has two versions: RSTP and PVST. Computers are the only ones who use the spanning-tree method. It guarantees a loop-free architecture and avoids bridge loops and the resulting broadcasting radiation as a protocol stack. In the event of an operational link breakdown, the protocol’s architecture provides spare connections as an automated backup.

Hence, the two versions are sometimes difficult to bifurcate. This article will help you understand the significance and functioning of RSTP and PVST based on their differences and mechanical assembly.

RSTP vs PVST

The difference between RSTP and PVST is that RSTP aka Rapid Spanning Tree Protocol (RSTP) enables much quicker spanning-tree resolution following a topology change when compared to PVST which is custom owned by Cisco. The RSTP is an improvement in the spanning tree protocol (STP) whereas the PVST follows the same STP principles with in-built Cisco enhancements.

RSTP stands for Rapid Spanning Tree Protocol and is a network management protocol for Ethernet connections that assures a loop-free architecture. Implementing redundant networking in important systems like Energy, Aviation, or Factory Automation is a common approach nowadays. The IEEE 802.1Q-2014 standard includes this interface.

IEEE 802.1D is the specification for RSTP. Within a grid range of interconnected layer-2 bridges, STP produces a tree structure. Ethernet exchanges are commonly used as layer-2 gateways.

PVST on the other hand stands for Per VLAN Spanning Tree is a Cisco closed source that dates back to the company’s inception. For each unique VLAN established in the system, it maintains a binary tree instance. It basically affects each VLAN separately. It employs Cisco’s patented ISL trunking technology and is built on the 802.1D specification.

Comparison Table Between RSTP and PVST

Parameters of ComparisonRSTPPVST
MeaningRSTP is a loop-free network protocol for Ethernet networks.PVST is a kind of solitary Spanning Tree Network. It maintains a distinct instance of Spanning Tree Protocol (STP) for each unique VLAN.
Full FormRapid Spanning Tree Protocol.Per-VLAN Spanning Tree
Proprietary ofThe IEEE 802.1Q-2014 standard includes this interface to run RSTP.PVST is only compatible with Cisco protocols. It itself is proprietary of Cisco.
Used inLAN (Local Area Network)VLAN (Virtual Local Area Network)
ExtensionsNo extensions available.Extensions of Cisco are available for VLANs with PVST.

What is RSTP?

Rapid Spanning Tree Protocol is the abbreviation of RSTP which is a loop-free network protocol for Ethernet networks. Rapid Spanning Tree Protocol (RSTP) enables much quicker spanning-tree resolution following a topology change when compared to PVST which is custom owned by Cisco.

The IEEE 802.1Q-2014 standard includes this interface. When infrastructure changes take place, RSTP delivers speedup over 802.1D STP. RSTP describes five port roles: root, authorized, auxiliary, backup, and deactivated, as well as three-port states: discarding, understanding, and pushing.

IEEE 802.1D is the guideline for RSTP. Within a mesh range of interconnected layer-2 bridges, STP produces a tree structure. Ethernet adapters are commonly used as layer-2 gateways. STP disables non-spanning tree connections, leaving just one active channel between any two nodes in the network.

RSTP also provides for the inclusion of spare and/or high availability in a network architecture. In the event that an active connection breaks, these provide automated backup pathways. Without the risk of bridge cycles or the requirement for periodic enabling/disabling of something like the fallback links, these spare links are incorporated.

What is PVST?

Spanning Tree Protocol (STP) is a kind of singularly mounted Spanning Tree Network which is usually dealt with when running the PVST compatibility with various VLANs. In large switched Frequent Spanning Tree (CST) networks, delays in receiving BPDUs are conventional. The time it takes to receive BPDUs might cause issues such as cluster formation.

PVST (Per-VLAN Spanning Tree) is a solution to these issues. Developed by Cisco Path Selection Protocol, Per-VLAN Spanning Tree (PVST) maintains a distinct instance of Spanning Tree Protocol (STP) for each unique VLAN. Each VLAN may be set up individually and function better with a change slightly of Spanning Tree Protocol (STP).

They can’t be utilized on most 3rd party routers since they’re Cisco’s patented implementation of the Spanning Tree Protocol. PVST+ is just another Cisco interface (Per-VLAN Spanning Tree Plus). PVST only operates with Cisco’s proprietary VLAN encoding technology, ISL. This one is due to the inherent Path selection ID in ISL, which is the based standardized protocol IP on ISL-capable Cisco switches.

This Cisco device can communicate with other PVST devices’ bridging trees, but never with IEEE 802.1Q computers. All of the ports on an IEEE 802.1Q device run on a single tree structure and the PVST is fully compatible with Cisco patented devices only.

Main Differences Between RSTP and PVST

  1. RSTP is compatible with all IEEE 802.1 router networks whereas PVST is only compatible with Cisco protocols.
  2. RSTP stands for Rapid Spanning Tree Protocol whereas PVST stands for Per-VLAN Spanning Tree.
  3. The RSTP is an enhancement on the multicast routing protocol, and it is an IEEE standard spanning tree, whereas the PVST is a Cisco patented spanning tree protocol.
  4. RSTP does not have any extensions whereas PVST is aided by Cisco to be compatible with other spanning tree setups.
  5. RSTP is mostly used in LANs whereas PVSTs are used in VLANs i.e. Virtual Local Area Network.

Conclusion

The spanning tree protocol is divided into two types: RSTP and PVST. The Path Selection is a network management protocol that is used in virtually every bridged Internet local network (LAN). In an Ethernet Network, STP provides a loop-free architecture. It accomplishes this by avoiding bridge loops and disseminating the resulting energy.

Cisco’s proprietary implementation of the Spanning Tree Protocol is the PVST. PVST enables each VLAN to have its spanning tree. PVST, rather than RSTP, which is commonly used in LANs, might be an excellent alternative for handling several networks at once.

References

  1. https://docs.commscope.com/bundle/fastiron-08090-l2guide/page/GUID-F9905D20-F2BB-4286-B606-49BC36596CF1.html
  2. https://www.accuenergy.com/support/reference-directory/rapid-spanning-tree-protocol-rstp/
x
2D vs 3D