2.4 Overlay Topology Design
| Field |
Value |
| Document Title |
Overlay Topology Design |
| Section Number |
2.4 |
| Version |
1.0 |
| Last Updated |
December 30, 2025 |
| Author |
Network Architecture Team |
| Classification |
Internal Use |
2.4.1 Overlay Topology Overview
Purpose and Scope
The overlay topology design defines the logical network structure that operates on top of the physical transport infrastructure. This design enables Abhavtech.com to create a secure, policy-driven WAN that abstracts the underlying transport complexity while providing deterministic application performance.
Topology Selection Criteria
| Criterion |
Hub-and-Spoke |
Partial Mesh |
Full Mesh |
Selected |
| Branch Count Support |
Excellent |
Good |
Limited |
Hub-and-Spoke |
| DC/Hub Traffic Pattern |
Optimal |
Good |
N/A |
Hub-and-Spoke |
| Branch-to-Branch Direct |
No |
Yes |
Yes |
Partial Mesh |
| Control Plane Scale |
Minimal |
Moderate |
High |
Partial Mesh |
| Tunnel Count |
Low |
Moderate |
High |
Partial Mesh |
| Management Complexity |
Low |
Moderate |
High |
Partial Mesh |
| Bandwidth Efficiency |
Lower |
Higher |
Highest |
Partial Mesh |
Selected Topology: Hierarchical Partial Mesh
OVERLAY TOPOLOGY - ABHAVTECH.COM
+==============================================================================+
| REGIONAL HUB LAYER |
| (Full Mesh Between Hubs) |
+==============================================================================+
| |
| +------------------+ +------------------+ |
| | MUMBAI DC |==========| CHENNAI DR | |
| | Primary Hub | IPsec | Secondary Hub | |
| | C8500-12X4QC | Mesh | C8500-12X4QC | |
| +--------+---------+ +--------+---------+ |
| | | |
| +----------+----------+ +----------+----------+ |
| | | | | | | |
+===|==========|==========|=======|==========|==========|======================+
| | | | | |
+===|==========|==========|=======|==========|==========|======================+
| | REGIONAL HUB LAYER | | REGIONAL HUB LAYER | |
+===|==========|==========|=======|==========|==========|======================+
| | | | | |
v v v v v v
+-------+ +-------+ +-------+ +-------+ +-------+ +-------+
|LONDON | |FRANK- | |NEW | |DALLAS | |BANGA- | |DELHI |
|Hub | |FURT | |JERSEY | |Hub | |LORE | |Branch |
|C8300 | |Hub | |Hub | |C8300 | |Branch | |C8200L |
+---+---+ |C8300 | |C8300 | +---+---+ |C8200L | +-------+
| +---+---+ +---+---+ | +-------+ |
| | | | | |
+====EMEA==+ +===AMER===+ +==INDIA===+
Hub Mesh Hub Mesh Spoke Only
|
+----+----+
| NOIDA |
| Branch |
| C8200L |
+---------+
+==============================================================================+
| TOPOLOGY SUMMARY |
+----------------------+-------------------------------------------------------+
| Hub-to-Hub | Full IPsec mesh (Mumbai, Chennai, London, Frankfurt, |
| | New Jersey, Dallas) = 15 tunnel pairs per transport |
+----------------------+-------------------------------------------------------+
| Hub-to-Branch | Hub-and-spoke (Bangalore, Delhi, Noida to nearest |
| | regional hub) = 6 tunnel pairs per transport |
+----------------------+-------------------------------------------------------+
| Branch-to-Branch | On-demand via regional hub (no direct tunnels) |
+----------------------+-------------------------------------------------------+
| Total Tunnels | 63 per transport × 3 transports = 189 tunnels |
+----------------------+-------------------------------------------------------+
2.4.2 Tunnel Architecture
Tunnel Types and Characteristics
| Tunnel Type |
Encapsulation |
Use Case |
MTU |
Overhead |
| IPsec (GRE) |
GRE over IPsec |
Standard tunnels |
1400 |
62 bytes |
| IPsec (IPSEC) |
Native IPsec |
High-performance |
1442 |
58 bytes |
| TLOC Extension |
Layer 2 |
DC interconnect |
1400 |
62 bytes |
| SIG Tunnel |
IPsec to cloud |
SASE/SIG |
1400 |
62 bytes |
Tunnel Color Assignment
TRANSPORT COLOR MAPPING
+==============================================================================+
| |
| COLOR TRANSPORT TYPE PREFERENCE SLA CLASS |
| ───── ────────────── ────────── ───────── |
| mpls Private MPLS WAN Primary Business |
| biz-internet Business-grade Internet Secondary Default |
| public-internet Consumer Internet Tertiary Bulk |
| lte LTE Cellular Backup Emergency Real-Time |
| 5g 5G Cellular (Future) Emergency Real-Time |
| private1 AWS Direct Connect Cloud-Pref Business |
| private2 Azure ExpressRoute Cloud-Pref Business |
| |
+==============================================================================+
SITE COLOR AVAILABILITY MATRIX
+-------------+------+------+--------+-----+----+----------+----------+
| Site | MPLS | Biz | Public | LTE | 5G | Private1 | Private2 |
+-------------+------+------+--------+-----+----+----------+----------+
| Mumbai DC | ✓ | ✓ | ✓ | ✓ | - | ✓ | ✓ |
| Chennai DR | ✓ | ✓ | ✓ | ✓ | - | ✓ | ✓ |
| London | ✓ | ✓ | - | ✓ | - | ✓ | ✓ |
| Frankfurt | ✓ | ✓ | - | ✓ | - | ✓ | ✓ |
| New Jersey | ✓ | ✓ | - | ✓ | - | ✓ | ✓ |
| Dallas | ✓ | ✓ | - | ✓ | - | ✓ | ✓ |
| Bangalore | ✓ | ✓ | ✓ | ✓ | - | - | - |
| Delhi | ✓ | ✓ | ✓ | ✓ | - | - | - |
| Noida | - | ✓ | ✓ | ✓ | - | - | - |
+-------------+------+------+--------+-----+----+----------+----------+
TLOC Configuration
Hub Site TLOC Definition (Mumbai DC)
! Mumbai DC WAN Edge 1 - TLOC Configuration
system
system-ip 10.1.100.1
site-id 100
organization-name "Abhavtech-SD-WAN"
vbond 13.234.xxx.xxx port 12346
!
! MPLS Transport TLOC
interface GigabitEthernet0/0/0
description MPLS-Transport-to-Provider
ip address 172.16.1.2 255.255.255.252
tunnel-interface
encapsulation ipsec weight 1
color mpls restrict
max-control-connections 2
no allow-service all
allow-service dhcp
allow-service dns
allow-service icmp
allow-service sshd
allow-service netconf
allow-service ntp
allow-service stun
allow-service bfd
!
!
! Business Internet Transport TLOC
interface GigabitEthernet0/0/1
description Business-Internet-Primary
ip address dhcp
tunnel-interface
encapsulation ipsec weight 1
color biz-internet
carrier Tata-Communications
max-control-connections 2
vmanage-connection-preference 5
no allow-service all
allow-service dhcp
allow-service dns
allow-service icmp
allow-service stun
!
!
! Public Internet Transport TLOC
interface GigabitEthernet0/0/2
description Public-Internet-Backup
ip address dhcp
tunnel-interface
encapsulation ipsec weight 1
color public-internet
carrier Airtel-Broadband
max-control-connections 1
no allow-service all
allow-service stun
!
!
! LTE Backup Transport TLOC
interface Cellular0/2/0
description LTE-Emergency-Backup
ip address negotiated
tunnel-interface
encapsulation ipsec weight 1
color lte
carrier Jio-4G
max-control-connections 0
no allow-service all
allow-service stun
low-bandwidth-link
!
Branch Site TLOC Definition (Noida)
! Noida Branch WAN Edge - TLOC Configuration
system
system-ip 10.1.105.1
site-id 105
organization-name "Abhavtech-SD-WAN"
vbond 13.234.xxx.xxx port 12346
!
! Business Internet Transport TLOC
interface GigabitEthernet0/0/0
description Business-Internet-Primary
ip address dhcp
tunnel-interface
encapsulation ipsec weight 1
color biz-internet
carrier Tata-Communications
max-control-connections 2
vmanage-connection-preference 5
no allow-service all
allow-service dhcp
allow-service dns
allow-service icmp
allow-service stun
!
!
! Public Internet Transport TLOC
interface GigabitEthernet0/0/1
description Public-Internet-Backup
ip address dhcp
tunnel-interface
encapsulation ipsec weight 1
color public-internet
carrier Airtel-Broadband
max-control-connections 1
no allow-service all
allow-service stun
!
!
! LTE Backup Transport TLOC
interface Cellular0/1/0
description LTE-Emergency-Backup
ip address negotiated
tunnel-interface
encapsulation ipsec weight 1
color lte
carrier Jio-4G
max-control-connections 0
no allow-service all
allow-service stun
low-bandwidth-link
!
2.4.3 Site Types and Roles
Site Classification Matrix
| Site Type |
Role |
Tunnel Behavior |
Route Preference |
Examples |
| Data Center |
Primary Hub |
Full mesh to all hubs, attract all traffic |
Highest (0) |
Mumbai |
| DR Site |
Secondary Hub |
Full mesh, standby for DC |
High (100) |
Chennai |
| Regional Hub |
Transit Hub |
Full mesh to other hubs, hub for branches |
Medium (200) |
London, NJ |
| Large Branch |
Spoke |
Hub-and-spoke to regional hub |
Default (500) |
Bangalore |
| Small Branch |
Spoke |
Hub-and-spoke, single WAN Edge |
Default (500) |
Noida |
| Remote Worker |
Edge |
Direct to cloud or hub |
Lowest (1000) |
Future |
Site-ID and System-IP Allocation
SITE IDENTIFICATION SCHEME
+==============================================================================+
| |
| REGION SITE SITE-ID SYSTEM-IP RANGE WAN EDGES |
| ────── ──── ─────── ─────────────── ───────── |
| |
| INDIA-DC Mumbai DC 100 10.1.100.1-2 2 (HA Pair) |
| INDIA-DR Chennai DR 200 10.1.200.1-2 2 (HA Pair) |
| INDIA Bangalore 103 10.1.103.1-2 2 (HA Pair) |
| INDIA Delhi 104 10.1.104.1-2 2 (HA Pair) |
| INDIA Noida 105 10.1.105.1 1 (Single) |
| |
| EMEA London 300 10.1.300.1-2 2 (HA Pair) |
| EMEA Frankfurt 301 10.1.301.1-2 2 (HA Pair) |
| |
| AMERICAS New Jersey 400 10.1.400.1-2 2 (HA Pair) |
| AMERICAS Dallas 401 10.1.401.1-2 2 (HA Pair) |
| |
+------------------------------------------------------------------------------+
| SITE-ID NUMBERING CONVENTION |
| ───────────────────────────── |
| 1xx = India Region (100=DC, 103-199=Branches) |
| 2xx = India DR Region (200=DR, 203-299=DR Branches) |
| 3xx = EMEA Region (300=Primary Hub, 301-399=Sites) |
| 4xx = Americas Region (400=Primary Hub, 401-499=Sites) |
+==============================================================================+
Hub Site Configuration
! Mumbai DC - Hub Site Role Configuration
policy
control-policy HUB-ROLE
sequence 10
match route
site-list BRANCH-SITES
!
action accept
set
tloc-action primary
preference 0
!
!
!
sequence 20
match route
site-list HUB-SITES
!
action accept
set
preference 100
!
!
!
default-action accept
!
!
apply-policy
site-list DC-SITES
control-policy HUB-ROLE out
!
!
lists
site-list DC-SITES
site-id 100
!
site-list DR-SITES
site-id 200
!
site-list HUB-SITES
site-id 100
site-id 200
site-id 300
site-id 301
site-id 400
site-id 401
!
site-list BRANCH-SITES
site-id 103
site-id 104
site-id 105
!
2.4.4 Topology Policies
Control Policy for Hub-and-Spoke
! Control Policy - Hub Preference for Branch Traffic
policy
control-policy BRANCH-TO-HUB
sequence 10
match route
site-list INDIA-BRANCHES
prefix-list CORPORATE-PREFIXES
!
action accept
set
tloc-list INDIA-HUBS-TLOC
tloc-action strict
!
!
!
sequence 20
match route
site-list EMEA-SITES
prefix-list CORPORATE-PREFIXES
!
action accept
set
tloc-list EMEA-HUBS-TLOC
tloc-action strict
!
!
!
sequence 30
match route
site-list AMERICAS-SITES
prefix-list CORPORATE-PREFIXES
!
action accept
set
tloc-list AMERICAS-HUBS-TLOC
tloc-action strict
!
!
!
default-action accept
!
!
lists
site-list INDIA-BRANCHES
site-id 103-105
!
site-list INDIA-HUBS
site-id 100
site-id 200
!
site-list EMEA-SITES
site-id 300-399
!
site-list AMERICAS-SITES
site-id 400-499
!
tloc-list INDIA-HUBS-TLOC
tloc 10.1.100.1 color mpls encap ipsec
tloc 10.1.100.2 color mpls encap ipsec
tloc 10.1.200.1 color mpls encap ipsec
tloc 10.1.200.2 color mpls encap ipsec
!
tloc-list EMEA-HUBS-TLOC
tloc 10.1.300.1 color mpls encap ipsec
tloc 10.1.300.2 color mpls encap ipsec
tloc 10.1.301.1 color mpls encap ipsec
tloc 10.1.301.2 color mpls encap ipsec
!
tloc-list AMERICAS-HUBS-TLOC
tloc 10.1.400.1 color mpls encap ipsec
tloc 10.1.400.2 color mpls encap ipsec
tloc 10.1.401.1 color mpls encap ipsec
tloc 10.1.401.2 color mpls encap ipsec
!
prefix-list CORPORATE-PREFIXES
ip-prefix 10.0.0.0/8 le 32
ip-prefix 172.16.0.0/12 le 32
ip-prefix 192.168.0.0/16 le 32
!
Topology Policy for Regional Affinity
! Control Policy - Regional Affinity
policy
control-policy REGIONAL-AFFINITY
sequence 10
match route
site-list INDIA-ALL
prefix-list ALL-PREFIXES
!
action accept
set
affinity-group preference 1 2
affinity-group 1
!
!
!
sequence 20
match route
site-list EMEA-ALL
prefix-list ALL-PREFIXES
!
action accept
set
affinity-group preference 3 4
affinity-group 3
!
!
!
sequence 30
match route
site-list AMERICAS-ALL
prefix-list ALL-PREFIXES
!
action accept
set
affinity-group preference 5 6
affinity-group 5
!
!
!
default-action accept
!
!
! Affinity Group Definitions
! Group 1: India DC (Mumbai)
! Group 2: India DR (Chennai) + India Branches
! Group 3: EMEA Primary (London)
! Group 4: EMEA Secondary (Frankfurt)
! Group 5: Americas Primary (New Jersey)
! Group 6: Americas Secondary (Dallas)
2.4.5 Tunnel Restrict and Preferences
Color Restrict Configuration
TUNNEL COLOR RESTRICTIONS
+==============================================================================+
| |
| USE CASE CONFIGURATION BEHAVIOR |
| ──────── ───────────── ──────── |
| |
| MPLS-Only Corporate color mpls restrict Only MPLS peers |
| Internet Breakout color biz-internet All colors peer |
| LTE Last Resort color lte Peer when needed |
| Cloud Direct Connect color private1 restrict Only cloud peers |
| |
+==============================================================================+
TLOC Preference and Weight
! TLOC Preference Configuration - Mumbai DC
interface GigabitEthernet0/0/0
tunnel-interface
color mpls restrict
preference 100 ! Highest preference for MPLS
weight 1
!
!
interface GigabitEthernet0/0/1
tunnel-interface
color biz-internet
preference 50 ! Medium preference for business internet
weight 1
!
!
interface GigabitEthernet0/0/2
tunnel-interface
color public-internet
preference 25 ! Lower preference for public internet
weight 1
!
!
interface Cellular0/2/0
tunnel-interface
color lte
preference 10 ! Lowest preference for LTE
weight 1
low-bandwidth-link ! Limit control connections
!
Tunnel Group Configuration
! Tunnel Groups for Load Balancing
sdwan
tunnel-group MPLS-GROUP
tunnel 10.1.100.1 color mpls
tunnel 10.1.100.2 color mpls
!
tunnel-group INTERNET-GROUP
tunnel 10.1.100.1 color biz-internet
tunnel 10.1.100.2 color biz-internet
tunnel 10.1.100.1 color public-internet
tunnel 10.1.100.2 color public-internet
!
tunnel-group ALL-TRANSPORTS
tunnel 10.1.100.1 color mpls
tunnel 10.1.100.2 color mpls
tunnel 10.1.100.1 color biz-internet
tunnel 10.1.100.2 color biz-internet
!
2.4.6 Tunnel Count Analysis
Per-Site Tunnel Calculation
TUNNEL COUNT ANALYSIS
+==============================================================================+
| |
| SITE TYPE PEER COUNT TRANSPORTS TUNNELS/PEER TOTAL |
| ───────── ────────── ────────── ──────────── ───── |
| |
| DC/DR HUBS |
| Mumbai DC 7 hubs 4 2 (HA) 56 |
| 3 branches 4 1-2 18 |
| ─── |
| Mumbai Total: 74 |
| |
| Chennai DR 7 hubs 4 2 (HA) 56 |
| 3 branches 4 1-2 18 |
| ─── |
| Chennai Total: 74 |
| |
| REGIONAL HUBS |
| London 7 hubs 3 2 (HA) 42 |
| Frankfurt 7 hubs 3 2 (HA) 42 |
| New Jersey 7 hubs 3 2 (HA) 42 |
| Dallas 7 hubs 3 2 (HA) 42 |
| |
| BRANCHES |
| Bangalore 2 hubs 3 2 (HA) 12 |
| Delhi 2 hubs 3 2 (HA) 12 |
| Noida 2 hubs 3 1 (Single) 6 |
| |
+------------------------------------------------------------------------------+
| OVERLAY SUMMARY |
| ─────────────── |
| Total Tunnel Endpoints: 17 WAN Edges |
| Hub-to-Hub Tunnels: 42 pairs × 3 transports = 126 |
| Hub-to-Branch Tunnels: 10 pairs × 3 transports = 30 |
| Total IPsec Tunnels: 156 (bi-directional counted once) |
| Effective Tunnel Count: 312 (counting both directions) |
+==============================================================================+
Tunnel Scale Limits
| Component |
Current |
Year 1 |
Year 3 |
Platform Limit |
| WAN Edges |
17 |
22 |
30 |
10,000 |
| IPsec Tunnels |
156 |
200 |
300 |
8,000 per vSmart |
| OMP Routes |
500 |
750 |
1,500 |
500,000 |
| Control Connections |
68 |
90 |
120 |
6,000 per vSmart |
2.4.7 Overlay Verification
Tunnel Status Verification
! Verify BFD Sessions
Mumbai-DC-WAN1# show sdwan bfd sessions
SOURCE TLOC REMOTE TLOC DST PUBLIC DST PUBLIC
SYSTEM IP SITE ID STATE COLOR COLOR SOURCE IP IP PORT ENCAP MULTIPLIER TIMEOUT(msec) UPTIME
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
10.1.100.2 100 up mpls mpls 172.16.1.2 172.16.1.6 12346 ipsec 7 7000 45:12:33
10.1.200.1 200 up mpls mpls 172.16.1.2 172.17.1.2 12346 ipsec 7 7000 45:12:30
10.1.200.2 200 up mpls mpls 172.16.1.2 172.17.1.6 12346 ipsec 7 7000 45:12:28
10.1.300.1 300 up mpls mpls 172.16.1.2 172.18.1.2 12346 ipsec 7 7000 45:12:25
10.1.300.2 300 up mpls mpls 172.16.1.2 172.18.1.6 12346 ipsec 7 7000 45:12:22
10.1.100.2 100 up biz-internet biz-internet 103.21.xxx.1 103.21.xxx.5 12346 ipsec 7 7000 45:10:15
10.1.200.1 200 up biz-internet biz-internet 103.21.xxx.1 203.0.113.10 12346 ipsec 7 7000 45:10:12
10.1.103.1 103 up biz-internet biz-internet 103.21.xxx.1 103.22.xxx.1 12346 ipsec 7 7000 45:08:45
10.1.103.2 103 up biz-internet biz-internet 103.21.xxx.1 103.22.xxx.5 12346 ipsec 7 7000 45:08:42
OMP Peer Verification
! Verify OMP Peer Status
Mumbai-DC-WAN1# show sdwan omp peers
DOMAIN OVERLAY SITE
PEER TYPE ID ID ID STATE UPTIME
---------------------------------------------------------------------------------
10.255.255.1 vsmart 1 1 0 up 45:15:22
10.255.255.2 vsmart 1 1 0 up 45:15:20
10.255.255.3 vsmart 1 1 0 up 45:15:18
10.255.255.4 vsmart 1 1 0 up 45:15:15
TLOC Table Verification
! Verify TLOC Table
Mumbai-DC-WAN1# show sdwan omp tlocs
-----------------------------------------------------------------------------------------------------------------
TLOC RECEIVED VIA ENCAP PREF WEIGHT ORIGINATOR COLOR STATUS BFD-STATUS
-----------------------------------------------------------------------------------------------------------------
10.1.100.1
mpls ompv2 ipsec 100 1 10.1.100.1 mpls C,Red up
biz-internet ompv2 ipsec 50 1 10.1.100.1 biz-internet C,Red up
public-internet ompv2 ipsec 25 1 10.1.100.1 public-internet C,Red up
lte ompv2 ipsec 10 1 10.1.100.1 lte C,Red up
10.1.100.2
mpls ompv2 ipsec 100 1 10.1.100.2 mpls R up
biz-internet ompv2 ipsec 50 1 10.1.100.2 biz-internet R up
public-internet ompv2 ipsec 25 1 10.1.100.2 public-internet R up
lte ompv2 ipsec 10 1 10.1.100.2 lte R up
10.1.200.1
mpls ompv2 ipsec 100 1 10.1.200.1 mpls R up
biz-internet ompv2 ipsec 50 1 10.1.200.1 biz-internet R up
10.1.103.1
mpls ompv2 ipsec 100 1 10.1.103.1 mpls R up
biz-internet ompv2 ipsec 50 1 10.1.103.1 biz-internet R up
public-internet ompv2 ipsec 25 1 10.1.103.1 public-internet R up
2.4.8 Topology Design Decisions
Design Decision Matrix
| Decision Point |
Options Considered |
Selected Option |
Rationale |
| Hub Connectivity |
Full mesh / Partial |
Full mesh |
6 hubs, manageable tunnel count, optimal latency |
| Branch Connectivity |
Direct mesh / Hub-spoke |
Hub-and-spoke |
Simpler management, policy enforcement at hub |
| Transport Priority |
MPLS first / Internet first |
MPLS primary |
SLA guarantee, existing investment |
| Color Restriction |
Restrict / No restrict |
Restrict for MPLS |
Keep private traffic on private network |
| Tunnel Encapsulation |
GRE/IPsec / Native IPsec |
GRE over IPsec |
Compatibility, multicast support |
| Regional Affinity |
Enable / Disable |
Enable |
Optimize regional traffic patterns |
Future Topology Considerations
| Enhancement |
Timeline |
Impact |
| On-demand branch mesh |
Phase 2 |
Enable direct branch-to-branch for latency-sensitive apps |
| 5G integration |
Year 2 |
Add 5G color for enhanced mobility |
| Cloud gateway sites |
Phase 3 |
Add cloud-based hub sites for SaaS optimization |
| Remote worker topology |
Year 2 |
Integrate remote access VPN with overlay |
2.4.9 Appendix: Overlay Topology Diagrams
Regional View - India
INDIA REGION OVERLAY TOPOLOGY
+==============================================================================+
| |
| +------------------+ |
| | vSMART-1,2 | |
| | Mumbai Cluster | |
| +--------+---------+ |
| | |
| | OMP Sessions |
| | |
| +-------------------+-------------------+ |
| | | | |
| v v v |
| +----------+ +----------+ +----------+ |
| | MUMBAI |========| CHENNAI |========| REGIONAL | |
| | DC HUB | IPsec | DR HUB | IPsec | HUBS | |
| | WAN1/WAN2| Mesh | WAN1/WAN2| Mesh | (4 sites)| |
| +----+-----+ +----+-----+ +----------+ |
| | | |
| | Hub-Spoke | Hub-Spoke |
| | | |
| +----+--------+-----+----+ |
| | | | |
| v v v |
| +--------+ +--------+ +--------+ |
| |BANGALORE| | DELHI | | NOIDA | |
| |Branch | |Branch | |Branch | |
| |WAN1/2 | |WAN1/2 | |WAN1 | |
| +--------+ +--------+ +--------+ |
| |
| LEGEND: |
| ======== Full Mesh IPsec Tunnels |
| -------- Hub-and-Spoke Tunnels |
| |
+==============================================================================+
Global View
GLOBAL OVERLAY TOPOLOGY
+==============================================================================+
| |
| CONTROL PLANE |
| +--------+ +--------+ +--------+ +--------+ |
| |vSmart-1| |vSmart-2| |vSmart-3| |vSmart-4| |
| |Mumbai | |Mumbai | |Chennai | |Chennai | |
| +---+----+ +---+----+ +---+----+ +---+----+ |
| | | | | |
| +-----+-----+-----+-----+-----+-----+ |
| | | |
| v v |
| +===================DATA PLANE - FULL MESH HUBS===================+ |
| | | |
| | MUMBAI<==========>CHENNAI<==========>LONDON<=======>FRANKFURT | |
| | ^ ^ ^ ^ | |
| | | | | | | |
| | +========+========+ +======+========+ | |
| | | | | |
| | NEW JERSEY<=========================>DALLAS | |
| | | |
| +==================================================================+ |
| | |
| v |
| +=================BRANCH SITES (HUB-SPOKE)=================+ |
| | | |
| | BANGALORE -----> MUMBAI/CHENNAI | |
| | DELHI -----> MUMBAI/CHENNAI | |
| | NOIDA -----> MUMBAI/CHENNAI | |
| | | |
| +===========================================================+ |
| |
+==============================================================================+
Document Control
| Version |
Date |
Author |
Changes |
| 1.0 |
December 30, 2025 |
Network Architecture Team |
Initial release |
This document is part of the Abhavtech.com SD-WAN Documentation Suite
Confidential - Internal Use Only