GigaPro features the ability to use a 2+0 link (two sets of links on the same path) to double the bandwidth without the use of an external switch.
2+0 Dual Modem Configuration – This is a double capacity link which utilizes two ODUs at each end of the link connected to a single IDU, combined on a single antenna (shown) or on separate antennas if desired. Each ODU pair forms a single RF link carrying up to 375 Mbps Full Duplex, for a total capacity of up to 750 Mbps Full Duplex.
- The Ethernet traffic is split between the two ODUs by the internal switch and then reassembled at the far end, enabling a single Ethernet port to be used if desired. Link aggregation mode is used to do this, with the hashing being done on both source and destination MAC and IP addresses. At least two flows to different MAC or IP destinations will be required to utilize the full capacity of the link.
- The 2 RF channels (F1 and F2) may be assigned in any frequency or polarization combination except on the same RF channel (co-channel). In addition, multiple channel bandwidths may be used if desired due to frequency congestion. Link reliability enhancement is in the form of hitless ACM on both active links, working independently such that frequency selective fading only affects one link. If one of the two links is disabled, the critical traffic is moved to the remaining link based on QoS rules.
- A license key is required to enable Modem 2 for two IDUs. Up to 4 ports of GigE copper, 32 ports of T1/E1 and 2 Optical ports (GigE fiber or STM-1/OC3) traffic may be used. (STM-1 and GigE Fiber ports are multiplexed)
- License keys are required for T1/E1 and STM-1/OC-3 operation

To activate 2+0 mode on the GigaPro, once the license key is loaded for dual modem operation, the sysconfig must be set to 2+0, the config saved and the system rebooted. Both RF links should be setup independently. Once both links are established, the GigaPro will split the traffic across the two modems/links based on source and destination MAC address (using standard LACP). The streams will be reassembled on the other end of the link.
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Dear,
Is there any command or thing to do to make the traffic be split into the 2 radios? Here we setup as shown, but when we make traffic between 2 computer connected to the ETH1 on each IDU, we can that only the Radio1 traffic (similar when we use ETH3 of each modem). Sysconfig 2+0 has been had been applied successfully in both modem, and all license are OK.
With only one computer on each side of the link in testing, you will only see the traffic go over one modem. You will need to have at least two computers on each side of the link for the MAC address hashing to work. At the simplest level, assume that all odd source MAC addresses go over modem one and even source MAC addresses go over modem two. The actual hashing method is more complex than this, but hopefully this example will help illustrate how it works.
At the basic level, you need multiple MAC addresses on each side for the traffic to be split accordingly. The more MAC addresses that are present on each side, the more evenly traffic can be split between the two modems.
You could probably simulate this with virtual machines (as long as the virtual networking is setup in a bridge mode where the unique MAC addresses come through) if you don't have multiple physical computers to test with.
So is that means routing traffic, like we are trying to do (we are using GigaPRO to connect to internet fiber of our internet provider, 2 BGP router communication), can not benefit from this 2+0 capability?
I'm told that the GigaPro will also do the hashing based on IP address, so it should work as long as you have multiple flows going across the link.
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