Network Help for ePMP

ninedd · May 21, 2016, 4:10am

Hi. This might seem like a bit of a strange question - but let me explain.

Our existing network consists of over 100 Access Points, and most of those Access Points are multi-port StarOS (Linux based) boards with up to 4 radio cards - each being a backhaul or a sector or an omni - so probably 300(ish) antennas. Each of those boards has complete routing (OLSR, OSPF, RIP, Static, etc) and so for us - the Access Points ARE the network hardware as well. Many of those boards have 2 or 3 or 4 Ethernet ports in them, so even on towers where there may be 10 antennas in play, that might consist of 3 of these StarOS/Linux/Router boards - and often the boards are all connected to each other via Ethernet. So in many cases, there are no other routers involved - and if there is a switch, its usually JUST a switch, with no smarts or routing ability. All our experience is with that design. So when we go to add a new sector, we hang the antenna and connect the board - and the board itself does the DHCPing, the routing, etc.

Now that we are transitioning to ePMP, the AP's are basically bridges. We have been putting them up and plugging them into our existing StarOS boards and then using StarOS to hand out DHCP numbers and to route the data and so on. That's working for now - BUT we've been doing this for 20 years and much of the network is frankly patched together and consists of different generations and fixes and duct tape and binder twine.

SO - as we continue to transition to ePMP, I want to do it ''right'' and rather than re-inventing the wheel by ourselves. So, I want to get some advice on what's in the shed and what people are using for their network routers and re-learn the 'basics' of how to build the network. We have a TON of experience with the RF side of things, but since our old RF boards also contain all the networking boards, we'll have to change our way of doing things . AND, since I have dozens and dozens of towers to do, I don't want to break the bank by doing it wrong and doing it over either.

giuseppe4 · May 21, 2016, 4:03pm

Hi ninedd,

In my company, we had the same issue before transitioning to ePMP.

We had a bridged network using all MikroTik AP and simple switches on the tower.

While we increased our users base, we understood that we had to switch to a routed, and better organized, network.

We had to think about the good "design" of each tower, and basically what we're doing now is:

1 main router (we use MikroTik for routing, it's very powerfull) in each tower. We're using CCRs which are powerfull enough for the most part of the towers. In the router we do all the network decision and we set up each port to have a specific use. For example:

Port 1: Backbone

Port 2: Backup Backbone

Port 3: Cambium APs

Port 4: MikroTik APs

And so on...

So we can put switches in each port when we have lots of APs on one tower.

Each Cambium AP works as a bridge, so the routing and auth is in the router.

To better manage the network, all APs have a static IP, so no DHCP.

Each tower is now following this scheme, so it's very simple to add new towers and new APs.

I think there isn't "a good way" and "a wrong way" to design your network. You have to choose the right thing based on your experience and your towers.

My advice is: try to find a good configuration, and use it on all your network, so everyone can look into and understand what you did.