Mesh Wireless (HWMP+)

Mesh Wireless (HWMP+)

Version Info

RouterOS 7.16 | Min: v6.0+ | :clock1: 25 minutes | :red_circle: Advanced

Tested on: 7.16 7.14

Version-specific notes

• All versions: HWMP+ requires legacy wireless driver - does NOT work with wifiwave2 (WiFi 6)

TL;DR (quick start)

For the impatient: create a basic wireless mesh between two nodes.

On all mesh nodes:

# Configure WDS on wireless
/interface wireless set wlan1 mode=ap-bridge wds-mode=dynamic-mesh \
    wds-default-bridge=none frequency=5180 ssid=mesh-network

# Create mesh interface
/interface mesh add name=mesh1 disabled=no

# Add wireless to mesh
/interface mesh port add interface=wlan1 mesh=mesh1

Verify:

/interface mesh fdb print
/interface wireless registration-table print

Overview

What this does: HWMP+ (Hybrid Wireless Mesh Protocol Plus) provides Layer 2 routing for wireless mesh networks. Based on IEEE 802.11s draft standard, it creates self-healing, loop-free paths between mesh nodes without requiring spanning tree.

When to use this:

• Outdoor wireless backbone networks (4-6 nodes)
• Temporary event coverage
• Rural/remote area connectivity
• Building-to-building links with redundancy

When NOT to use this:

• WiFi 6 (802.11ax) devices - HWMP+ doesn’t work with wifiwave2
• Networks larger than 4-6 nodes - scaling issues
• Networks requiring multicast/OSPF - poor multicast support
• Enterprise deployments - use CAPsMAN instead

Two Operating Modes:

Mode	Description	Best For
Reactive	On-demand path discovery via PREQ flooding	Mobile nodes, intra-mesh traffic
Proactive	Portal announces routes via RANN	Gateway/internet traffic

Prerequisites:

• Devices with legacy wireless driver (not wifiwave2)
• Same SSID, frequency, and security on all nodes
• WDS-capable wireless configuration

Common Mistakes

• Don’t use HWMP+ with wifiwave2/WiFi 6 devices - it won’t work
• Don’t scale beyond 4-6 nodes - protocol becomes unstable
• Don’t run OSPF or other multicast protocols over mesh - causes storms

Configuration steps

Step 1: configure WDS on wireless

WDS (Wireless Distribution System) enables multi-hop forwarding with four-address frames:

/interface wireless set wlan1 \
    mode=ap-bridge \
    wds-mode=dynamic-mesh \
    wds-default-bridge=none \
    frequency=5180 \
    ssid=mesh-network \
    security-profile=default

WDS Modes:

• dynamic-mesh - Auto-create WDS links, optimized for mesh (recommended)
• dynamic - Auto-create WDS on any compatible peer
• static - Manual WDS links only

Step 2: create mesh interface

/interface mesh add name=mesh1 disabled=no

Step 3: add ports to mesh

# Add wireless interface
/interface mesh port add interface=wlan1 mesh=mesh1

Step 4: repeat on all nodes

Configure identical settings on all mesh participants. They will automatically discover each other and form mesh paths.

Portal configuration (proactive mode)

For networks where most traffic goes to/from a gateway:

On gateway node (portal):

/interface mesh add name=mesh1 disabled=no mesh-portal=yes
/interface mesh port add interface=wlan1 mesh=mesh1
/interface mesh port add interface=ether1 mesh=mesh1

On internal nodes:

/interface mesh add name=mesh1 disabled=no mesh-portal=no
/interface mesh port add interface=wlan1 mesh=mesh1

The portal announces itself via RANN messages. Internal nodes learn default route to portal and forward unknown destinations there.

Mixed WDS and ethernet

Include wired links in the mesh:

/interface mesh add name=mesh1 disabled=no
/interface mesh port add interface=wlan1 mesh=mesh1 port-type=wds
/interface mesh port add interface=ether2 mesh=mesh1 port-type=ethernet path-cost=5

Lower path-cost makes Ethernet preferred over wireless.

Bridge local clients

Connect local clients to the mesh network:

# Create bridge for local clients
/interface bridge add name=bridge-local

# Add local interfaces
/interface bridge port add interface=ether2 bridge=bridge-local
/interface bridge port add interface=wlan2 bridge=bridge-local

# Add bridge to mesh
/interface mesh port add interface=bridge-local mesh=mesh1

Mesh properties

Interface properties

Property	Default	Description
mesh-portal	no	Act as gateway for proactive mode
reoptimize-paths	no	Periodically revalidate paths
hwmp-default-hoplimit	32	Maximum hop count
hwmp-prep-lifetime	5m	Route lifetime
hwmp-rann-interval	10s	Portal announcement interval

Port properties

Property	Default	Description
path-cost	10	Routing cost (lower = preferred)
port-type	auto	wds, ethernet, or wireless
hello-interval	10s	HWMP+ hello frequency

Verification

# Mesh interface status
/interface mesh print

# Mesh ports and neighbors
/interface mesh port print detail

# Forwarding database (learned MACs)
/interface mesh fdb print

# Trace path through mesh
/interface mesh traceroute mesh1 00:11:22:33:44:55

# WDS peer connections
/interface wireless registration-table print

FDB Entry Types:

• local - MAC on directly connected port
• neighbor - MAC reachable via mesh neighbor
• mesh - MAC reachable via multiple hops
• outsider - MAC outside mesh (via portal)

Troubleshooting

Symptom	Cause	Solution
Mesh unstable after few minutes	HWMP+ instability with many nodes	Limit to 4-6 nodes
No WDS peers connecting	Wrong WDS mode or SSID mismatch	Check wds-mode=dynamic-mesh, same SSID
Ethernet stuck as “outsider”	Port type detection issue	Set port-type=ethernet explicitly
WiFi 6 devices don’t mesh	wifiwave2 not supported	Use legacy wireless driver only
Traffic doesn’t use better path	Cost-based routing limitation	Manual intervention; accept limitation
High CPU usage	ANI issues	Disable: adaptive-noise-immunity=none
Multicast storms	No optimized L2 multicast	Avoid multicast; don’t run OSPF over mesh

Community Tips

• Keep mesh networks small (4-6 nodes max) - protocol has scaling limitations
• For larger deployments, use Layer 3 routing (OSPF) instead
• WDS + RSTP is simpler alternative if you don’t need optimal routing
• CAPsMAN is better choice for managed WiFi 6 deployments

HWMP+ vs alternatives

Feature	HWMP+ Mesh	WDS + RSTP	CAPsMAN
Optimal routing	Yes	No (loop prevention only)	N/A
Scalability	4-6 nodes	6+ nodes	Many APs
Self-healing	Yes	Yes	Yes
Multicast	Poor	Better	Good
WiFi 6 support	No	No	Yes
Configuration	Medium	Simple	Medium

Limitations

• Does NOT work with wifiwave2 (WiFi 6) interfaces
• Scaling issues beyond 4-6 nodes
• Poor multicast/broadcast support
• Cost-based routing may not function properly
• Ethernet ports may get stuck as “outsider”
• No interface hopping for dual-radio mesh

Common Mistakes

• Don’t expect mesh to scale like enterprise WiFi - it’s designed for small deployments
• Don’t run multicast protocols (OSPF, mDNS) over mesh - causes network instability
• Don’t mix wifiwave2 and legacy wireless in the same mesh

Related topics

WiFi alternatives

• CAPsMAN - centralized management for enterprise WiFi (recommended)
• WiFi Basic Setup - single AP configuration

Network infrastructure

• Bridge Configuration - connecting local clients to mesh
• VLAN Configuration - segment mesh traffic
• Ethernet Interfaces - wired mesh ports

Routing

• OSPF - Layer 3 alternative for large networks
• Static Routes - manual routing through mesh

Security

• Firewall Basics - protect mesh traffic
• User Management - wireless authentication

Monitoring

• IP Neighbors - discover mesh devices
• Torch - analyze mesh traffic

Reference

• MikroTik HWMP+ Documentation
• IEEE 802.11s - Wireless Mesh Networking Standard