surprise

Hello Folks,
It’s really a marvel in the world of canopy, i was called by a provider to do an alignment of his BH’s but to my surprise he’s not using reflectors for his BH, i have not done that before, i am used to REFLECTORS with BH’s and if that’s not a enough in his IP ADDRESS he has no GATEWAY IP ADDRESS just 0.0.0.0 , is that meant to be his GATEWAY ? But i could not get the two BH’s registered , i did ask him to get REFLECTORS.
If i am not wrong about all this, i just want the forum to put me through if it is ok to do BH without Reflectors or no gateway on ADDRESS.
I look forward to your useful advice
Blink

if the distance is under 2 miles that should be fine. you would only need reflectors if its over 2.5 miles


if he receives his IP via dhcp or dynamic then it could be possible to have a 0.0.0.0 ip address if he is not registered to the backhaul that has the dhcp server. for example


customer —> backhaul ----> <----backhaul -----dhcp server and internet

if the backhaul link is broken then he wouldnt have access to the dhcp server.

Hi Vince,
The provider never gave me the whole details bcos i just called to align the BH’s, he said they were working for a longtime before they just did a reinstallation. But i found out that it is an office they were giving the connection to but want to extend this connection to another site using 2 BH’s. the diagram is just like this office site with internet connection backhaul -------> backhaul 2.
i even thought if this guy dont have a gateway then he must be using the mastre as the gateway for the slave which i tried but it is not still working.
The 2 BH’s are seeing each but they are not registering, i thought of interference but i did a scan but the interference is not strong .
I have strongly thought reflectors can come in handy.
Thanks for yourt advice
Blink

what is the fade margin? What is the noise floor and the rx signal at both ends? If you are not above the noise floor more then 6 to 10 db then add the dishes. As far as the gateway address this is only for management traffic. On a single link no gateway is fine.

we dont put gateways in our infrastructure equipment, what would make that neccessary? our entire infrastucture is bridged.

If you have a flat network I cannot see a need to require the gateway, however once you start breaking up and routing your network you will need it in order to get your management traffic to where it is supposed to go.

Remember, large flat networks (or broadcast domains) are a bad thing!


Remember, large flat networks (or broadcast domains) are a bad thing!


tell me about it
thatoneguysteve wrote:

Remember, large flat networks (or broadcast domains) are a bad thing!


tell me about it


Imagine for a moment you have a network that only has one router, and several switches. Now, let's say you have a client on your system who gets infected with a worm or other malware of that nature. This worm begins broadcasting looking for more hosts to infect. This broadcast message goes to everything on your network - every server, ap, sm, computer. When these devices receive the broadcast, they in turn send out another broadcast of their own, to every node on your network. With every broadcast a node receives, it sends out another response in the form of a broadcast. You basically have a snowball effect.

What ends up happening is these broadcasts, if uncontrolled, will eventually consume all of your network resources so that legitimate traffic can no longer flow smoothly. One infected Windows box can take down a whole network - we actually learned this the hard way early on.

One way you can alleviate the issue for the short term is put a router on every customer site or put their SMs in NAT mode. What this effectively does is segments their network from you. Routers do not pass broadcast traffic, so you can help mitigate the effects with the use of it. A well designed network will keep its broadcast domains as small as feasibly possible - that way if a broadcast storm does occur, it will only effect a small portion of the network, rather than disrupting the whole network.

The other downside to flat networks on a large scale is they are very inefficient. Routed networks only pass traffic where it needs to go, keeping the junk traffic off of your backhauls and other backbone infrastructure.

Hope that helped explain it a bit.

I agree with Wifiguy. We originally started out with one large broadcast domain, what we found was that when one person started storm broadcasting because of a virus the entire systems health and integriity was down.

We have adopted since our first woes a routed and very segmented network topology.

We have 27 tower locations as of today, each tower gets a Cisco 1605R or 1711. Up until a month ago we were handing out RFC1918 DHCP assignments from the routers at each tower in the 172.16.x.x networks, recently we have changed to public routable IP space assignments via DHCP at each tower router.

All equipment on our network whether Motorola, Alvarion or otherwise is assigned 192.168.x.x ip space for management and monitoring only.

What this has done for us, is allow us to troubleshoot more effectively any problems, isolate those problems to one small segment of the network and ultimately because each tower is in itself it’s own network reduce our support calls and truck rolls.

The largest broadcast domains I allow are no larger than /26 networks, with the exception of 3 DHCP pools which are /25’s.

The additional positive to this, is the customers have also noticed lower latency and increased throughput to there desktops.

–SDH