Have anyone able to use etherWAN from Cambium. Will this really works for link aggregation using combination of PTP650 & PTP500 in parallel.

How much is this device anyway?


EtherWAN is just a brand of hardened switches, you do not have to use them. I have not found too many high bandwidth users whom like them but the temps that they work at is impressive. They are limited in their backplane switching bandwidth (all switches are) not as bad as a soho switch (which has between 2 and 12 Gbps depending on number of ports and intended market) but also not as good as 36Gbps as found on cisco 24port 3650Gā€™s. We made a decision to not use etherWAN equipment because we use cisco switches everywhere else. This saves us from having two different CLI languages and makes keeping spares simple.

We have a couple of epmp ptp links that are doubled up using lacp port channels in active/active mode. What this does is allow us to spread the data streams over both links. But this does not split data streams! Eg: if you have a link that is almost full and add another link beside it, the new link will not get used until the first fails to pass several bpdu packets. By using port channels I can split data streams by MAC addresses. Cisco hardware does this automatically but its behaviour can be controlled.

A better method is to build what looks like a mesh network and use MPLS-TE to spread the load. This allows redundancy and off loading a saturated link through another tower. Its more complicated but the gains and the ability to dedicate bandwidth are worth it. Just make sure you keep a minimum of two ptp links per node tower that feeds a leaf tower and its easy to step a leaf into a node. To double up a link in active/active, just tell the routers at each location that there is a new link; use a different access vlan on each switch port. Eg first link is vlan 10, new link uses vlan 11. The router will automatically add the link into the lable directory as another path to the other router. So first link may be given the link id 35, the second may be 96 but both routers know that they can use either. Now the TE part allows you to specify a path through your nerwork and set aside guaranteed bandwidth for a client and the best part is the path does not have to be the same in each diection! You can choose to setup alternate paths for uplink and downlink.
We are deploying/converting to this setup as it is much more flexible. This also allows spanning tree to do its job and gets rid of our spanning tree blocking that is manditory for port channels to work in active/active mode without killing a link.

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