Bay Area Backbone

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Bay Area Backbone, Goal 2024.png

The goal of the Bay Area Backbone Project is to provide a fast, IP microwave based networking between amateur high sites in the Bay Area. The backbone provides IP connectivity within the network and can provide public IPv4 address for full Internet connectivity.

The network is available to any amateur operator needing connectivity to, from or between supported sites.

We provide an Internet as last resort for many locations.



Want to become part of the network? We'll provide everything you need to get connected.


American Registry for Internet Numbers


Points of Contact


Autonomous System Numbers


The subnet allocation is kindly provided by the ARDC.


Federal Communications Commision

  • FRN: 0031037245

Experimental Licenses

A number of the backbone links operate with experimental 6GHz licenses in the U-NII-5 band.

Network Structure


A minimal backbone endpoint consists of two radios providing a point-to-point link between two sites. Ideally a site provides at least two links so the network can be extended from that point. In some places we use point-to-multipoint radios to provide additional shared links from a single site. We currently deploy the following:


Any router capable of supporting OSPF can be used to support the radios. We currently deploy the following:


The backbone network runs OSPF


More details description of typical site hardware.


A typical backbone node provide the following services:

  • Private IPv4 address: A subnet of 100.100.X.X/24 is assigned to the router. Addresses from this range can be automatically or statically allocated to devices connected to the router. All addresses can be routed to the Internet (but not from the Internet). The subnet is allocated to VLAN 1100 internally. A router may choose to restrict this using a firewall.
  • Public IPv4 address: Specific public IP address from the subnet or can be allocated to specific routers and/or ports. Traffic to these addresses can be routed to and from the Internet. Addresses are managed using policy based routing. No traffic is routed into the network for an address which is not allocated.
  • Public IPv6 address: A subnet of 2620:B8:A000::/64 is assigned to the router. Addresses are allocated to a device using SLAAC. Traffic to these addresses can be routed to and from the Internet. A router may choose to restrict this using a firewall or choose to not participate in IPv6 routing at all.






IP Transit and Internet Exchanges

Hurricane Electric

The backbone network's IP Transit is provided by Hurricane Electric at the Fremont 2 location.

Internet Exchanges

Detailed peering information can be found on PeeringDB or

Our peering policy is here.


ARIX is an internet exchange point for licensed amateur radio operators for the use of networking research, development, and education.

  • PeeringDB
  • Authorization
  • BAM IPv4:
  • BAM IPv6: 2602:801:30ff::20/64
  • ARIX IPv4: &
  • ARIX IPv6: 2602:801:30ff::253 & 2602:801:30ff::254


EVIX is an Experiment Virtual Internet Exchange.



FCIX is the Fremont Cabal Internet Exchange.

  • PeeringDB
  • Authorization
  • BAM IPv4:
  • BAM IPv6: 2001:504:91::172/64
  • FCIX IPv4: &
  • FCIX IPv6: 2001:504:91::253 & 2001:504:91::254


FREMIX is the Fremont Internet Exchange.

  • PeeringDB
  • Authorization
  • BAM IPv4:
  • BAM IPv6: 2001:504:125:e0::67/64
  • FREMIX IPv4: &
  • FREMIX IPv6: 2001:504:125:e0::1 & 2001:504:125:e0::2

We directly peer with additional networks via FREMIX:

Old Transit

The backbone network previously used two IP Transit points to facilitate access to and from the public Internet using BGP.


The first backbone link, between Fish Ranch and San Bruno Mountain, was installed on the 23rd November, 2021 and became operational on 3rd September, 2022. The goal was to provide a solid connection across the Bay which the AREDN network could use. It had been observed by the AREDN network builders in Southern California, that a better quality and more stable network could be constructed by creating a solid, well engineered backbone, to which local community AREDN networks could connect.


Bay Area Mesh on the Backbone

Using the Bay Area Backbone to support the Bay Area Mesh has a number of advantages for the Mesh:

  • It easier to connect high sites to other high sites, especially when we're trying to connect different neighborhoods while avoiding mountain ridges.
  • High sites are often backed up with generator power. We provide battery backup ourselves, but that will only last so long.
  • High sites will be there when the Ham moves on. Because these are generally commercial sites with long histories of ham involvement, we are not a the whims of someones current housing situation or - in some cases - employment situation.
  • It's often easier for a neighborhood to connect up to a high site (or more than one) as they're less obstructed.


The current health of the backbone is monitored here (internet)


The mesh operates on the Backbone by creating point-to-point connections between mesh sites (these are called xlinks - see below). Mikrotik hAP ac2 nodes provide the the mesh endpoint hardware. The traffic is routed between the specified IP addresses of the xlink. The underlying network may encapsulate this traffic if desired. We often use VLANs.


XLINKS are custom connections between sites which feed directly into the AREDN router. Think of them as DtD links, but only point-to-point. By default we use VLANs 1100, 1101, 1102, etc. for all XLINKs.

Backbone links appear in the mesh labeled as xlink but are no different from any other link in the network from AREDN's perspective.

WB6ECE Repeater Group Interconnect

WB6ECE Repeater Group operates a network on about a dozen sites south of the Bay Area. The interconnect project aims to share networks to provide greater redundancy and reduce duplicated effort.

The ultimate goal of the Interconnect project is to provide a BGP connection between the two. For the moment the networks are interconnected by each providing the other with IP addresses on their respective networks.

Interconnect Points

San Bruno Mountain (Building 7)

Routers at San Bruno Mountain are connected via a 1 Gbps link.

Forward Link

  • BAB IP:
  • WB6ECE IP:
  • Subnet:
  • Routes:

Reverse Link

  • WB6ECE IP:
  • Subnet:
  • Routes:

Black Mountain (Site 4)

Router at Black Mountain is connected to Site 5 via a 60 GHz link.

Forward Link

  • BAB IP:
  • WB6ECE IP:
  • Subnet:
  • Routes:

Reverse Link

  • WB6ECE IP:
  • Subnet:
  • Routes:

Mount Allison

Forward Link

  • BAB IP:
  • WB6ECE IP:
  • Subnet:
  • Routes: -

Reverse Link


Interconnect Links


  • Tim Wilkinson - KN6PLV -