EGVRP/GVRP Simulation IEEE 802.1 May 2004 Guyves Achtari Paul Bottorff

1. EGVRP/GVRP SimulationIEEE 802.1 May 2004Guyves AchtariPaul Bottorff

2. EGVRP Basic Concepts • S-VLAN Distribution Protocol for Provider Bridges • Supports large S-VLAN address spaces up to 224 • Uses a network wide address size parameter to determine the number of active bits from 12 to 24 • Maintains hard state to scale better • Supports a “Dense” protocol mode for startup • Supports a “Sparse” protocol mode for add/change updates • Normal carrier operation would only use “spare” mode

3. index range 4095 16773120 … 16777217 2^^24 ……. 5 20482 … 24577 2^^15 4 16386 … 20481 2^^15 3 12290 … 16385 2^^14 2 8195 …. 12289 2^^14 1 4098 …. 8193 2^^13 0 1 ….. 4097 2^^12 EGVRP’s dense mode 224 S-VLANs require 4095 fully populated frames of 4096 dense packed attributes to update the entire database. MIB: Unified Address Size index:4095 header 4096 encoded vlans type =2 index One Applicant engine per index dense mode index:0 Each 4096 S-VLANs are grouped together. Each group is represented by an array of 4096 state machines. Up to 4096 indexed arrays correspond to 224 S-VLANs. Applicant engine: 1 global Transmit PDU Registrar engine: 1 leave timer per vlan

4. EGVRP model index:4095 index:4095 One Applicant engine per index One Applicant engine per index index:0 index:0 Applicant engine: ONE global Transmit timer for all VLANs Registrar engine: 1 leave timer per VLAN Applicant engine: ONE global Transmit timer for all VLANs Registrar engine: 1 leave timer per VLAN GIP MAC Relay Entity Leave timers are internal timers. They do not regulate transmissions. Only one Transmit timer per index per port regulates all transmissions for a set of S-VLANs header 4096 encoded vlans type =2 index dense mode header Attribute List type =1 sparse mode

5. EGVRP/GVRP Simulator • Written in ‘C’ code • Allows creation of any bridge topology • Creates a model with asynchronous operation of each bridge modeled in the topology • Simulates EGVRP and GVRP state machines • Simulator is new and still under test. All results are preliminary and still being verified.

6. Bridge Node of Simulation Model Propagation delay Port 0 Port 1 Port 2 State machine update delay (per vlan) State machine update delay (per vlan) State machine update delay (per vlan) Code Calculation delay ( dense mode, per vlan) Code Calculation delay ( dense mode, per vlan) Code Calculation delay ( dense mode, per vlan) Pack/unpack delay Pack/unpack delay Pack/unpack delay link delay link delay link delay

7. Simulated Bridge Assumptions • Bridge’s control plane can process 10K EGVRP frames/second • Order of magnitude faster than today’s Bridge control planes • Simulation times are normalized to GVRP rates • Bridge’s S-VLAN database can be updated fast enough to keep up with the EGVRP frames/sec processing rate • Allows including the database update times into the packet processing time

8. 19 nodes Network Under Simulation • Simulation of a tree topology with 19 nodes • -The 10 edge nodes contain static initial S-VLAN databases • - Each initial S-VLAN database is different from all other initial databases • All S-VLANs are configured in at least 2 edge nodes • - Convergence is achieved when all S-VLAN databases in all nodes are identical

9. Preliminary Simulation ResultEGVRP With 212 to 223 S-VLANs Convergence Time Normalized To GVRP For 212-2 VLANs EGVRP GVRP 212-2 S-VLANs ~221 Simulation shows convergence time is almost flat for increasing S-VLANs address spaces

10. Future Work • Perform simulations which vary the relationship between the protocol processing time and database update time for large S-VLAN spaces. • It is believed the simulations results are heavily dominated by the 200 msec transmit timer. We will investigate alternate timer values to determine the impact on the convergence time. • Perform simulations over more varied topologies including rings of trees and larger populations up to 100 node networks. • Investigate the relative performance of EGVRP to GVRP with large S-VLAN spaces. • Further simulations will be done to determine if dense mode EGVRP really provides a significant performance advantage.

11. Backup

12. Simulation model for protocol delays (dense mode) Maximum protocol cost at start-up, when each sub-set of a set provokes two join declarations In compact mode 4096 S-VLANs are packed in a frame. Worst case: happens when sub-sets of a set of S-VLANs can not merge their declarations before the transmit timer for that set expires Example below: If different sub-sets of the same set reach a bridge while the timer for that set has not expired, declarations can be merged and sent together 4096 encoded vlans header type =2 1 1 20-40 4097 header type =2 1 1 40-60 4097 case 1: see explanation in notes time case 2: see explanation in notes time Transmit timer time leaf1 leaf2 case 3: see explanation in notes

13. Tree topology: same load, expanded network 9 nodes Node specifications (Same as before) 19 nodes 39 nodes

14. Simulation results:This chart shows convergence time in a tree topology network with 9,19 and 39 nodes time nodes