Sync Questions

I have some co-existance questions about syncing with a competitor (See my forum titled “Interference”)

All of my towers have single Canopy radios. As they are all quite some distance from each other (10+ miles) I always had them generating their own sync. The one exception I am passing the sync from the SM to the AP - that repeater is 6 miles from the AP.

My primitive understanding is that if I sync all my AP’s together this would help with self interference but unless I am physically connected to the competitor’s network they would still interfere with me.

The competitor seems to think if I install individual sync pipes at each of my locations all of our equipment will sync - the GPS pulls the information from a Satellite and syncs accordingly.

That would mean that if every WISP was receiving Sync nobody would ever interfere with each other???

Last question, is there a device that will allow me to sync over Ethernet so all my AP’s can receive sync from a central location as opposed to having separate GPS receivers at each tower? If not, is there a device that will at least let my sync to the Ethernet port so I don’t have to run new cables of the towers to the Sync ports?

What the syncing will do is ensure all of your devices transmit at the same time and listen at the same time. You still have to coordinate channels and configure your APs the same to avoid interference (your control slots and downlink percentage come into play).

You can co-exist effectively if your competitor is using Canopy and you are both synced and using similar settings, however if they are using another vendor you will run into issues.

As for the last question, look into the Syncpipe Parisitic from packetflux (www.packetflux.com). You can connect those units to the POE run going up the tower, then you just need to run an ethernet jumper and a timing cable from that unit to your AP. This is rather easy when you locate the syncpipe near your AP.

Yes, they are running Canopy.

So as long as I’m receiving GPS sync and they are receiving GPS sync we don’t need to be connected in any way? I understand about setting the control slots, max range, DL, etc.

Is there a GPS receiver that will allow me to connect to the Ethernet port of the AP and keep the receiver at the base of the tower? I’m trying to avoid a tower climb…

No, you shouldn’t need to be connected to their network or APs in any way.

You could look at injecting your sync through the power. Packetflux also has a unit that does this and will provide sync to up to 4 devices with the ability to daisy-chain and accommodate additional units. You’d need a standard syncpipe and syncinjector from them. The syncpipe could then be installed either on the roof of your shed or at the base of your tower. The syncinjector will replace the Canopy power injector. It’s the same concept at the CMM from Motorola.

Does anyone make a basic sync pipe type device that will connect to the ethernet/power port? The synjector and sync pipe are overkill for my single AP sites…

If you only need to sync a single AP - this is all you need:

http://www.packetflux.com/index.php?mai … e5834f4775

You need to climb the tower or use the SyncInjector/SyncPipe combo

Hey!

Just to clarify: Our your towers interconnected, or do you have independent bandwidth sources feeding each site?

If they were interconnected via backhaul links, you could just kind of daisy-chain the sync along. If the towers aren’t linked, you’d need a seperate sync device at each site.

He’s trying to avoid a tower climb at each site. Every solution I know of other than the syncinjector will require a timing cable be ran.

Hence my comment:

You need to climb the tower or use the SyncInjector/SyncPipe combo

Was directed at newcastle, but yeah.

Some of the towers are interconnected. One in particular I’m wondering because it is a SM feeding an AP. Would it be safe to pass the sync from the SM to the AP or does the Sync Pipe work better?

Also noticed the Packetflux gear is on back order. Advantages/Disadvantages to using the CMMmicro as opposed to the synjector?

I would recommend having a separate sync device at each tower site if at all possible - more reliable and accurate.

As for the CMM micro vs syncinjector - expense is going to be a major factor. The other thing is the syncinjector has no way other than serial connection to check GPS status.

Hey!

I read it as he didn’t want to run new wires up the towers to the sync ports, not that climbing the tower was out, but I guess that’s established. My bad. Seems like it would be cheaper to have some monkey run up there with a five dollar cable, but to each his own. :roll:

I personally would go with a single CMM micro and pass the sync with sync cables from the SM (or whatever) to the AP, on down the line, particularly if the majority of the towers are interconnected.

Having several different GPS points-of-failure, each only accessable through a serial cable, makes me nervous just thinking about it.

Unfortunately the AP in question is on a tower that only the owner’s approved riggers can climb and they charge $2k minimum.

newcastle wrote:
Hey!

I read it as he didn't want to run new wires up the towers to the sync ports, not that climbing the tower was out, but I guess that's established. My bad. Seems like it would be cheaper to have some monkey run up there with a five dollar cable, but to each his own. :roll:

I personally would go with a single CMM micro and pass the sync with sync cables from the SM (or whatever) to the AP, on down the line, particularly if the majority of the towers are interconnected.

Having several different GPS points-of-failure, each only accessable through a serial cable, makes me nervous just thinking about it.


Having a single point of failure makes me even more nervous. If your CMM fails your whole network goes down.

Hey!

OK; lord knows i can stand (and even sit) to be corrected.

This thing;

"The SyncPipe has three jacks in it’s interior - two RJ45’s which act as a PoE passthrough, allowing the SyncPipe to borrow enough power to operate, and a single 6P6C jack which provides sync to the attached radio via a customer-provided 6 Pin Modular (RJ11-like) cable. Additional radios can be connected to this device by using a SyncSplitter (additional cost). This unit is not suitable to provide sync to a SyncInjector without creative wiring."


is basically a GPS antenna that borrows power from the Canopy power over ethernet, and then ‘injects’ sync via the (RJ11-like) cable, which means a phone line into the timing port.

You still have to plug it into the timing port, right? atop the tower, is my point, not trying too hard to be a hardon. Even if it works at ground level, don’t you still have to plug it into the timing port on a unit atop the tower?

It’s a GPS antenna purely, without a graphic user interface or means of remote access, unless you have a server at the tower site to facilitate that kind of connection via a serial link.

If I’m missing something, or leading someone astray, that is not my intent. I get that it’s inexpensive to do the injector. Time has a certain value, as does gasoline. Of course, I have the luxury of never having had a CMM micro fail, and I doubt that’s the norm.

i have no personal experience with the sync injector thing. Can’t say what it takes to hook it to a Canopy unit other than the link i quoted, followed from a previous post. Have many CMM micros with no complaints, some passing sync through two hops in our network chain. I can log into them via IP and see if their GPS is working.

yall rock.

Yes, you run a timing cable from the parasitic to the AP, atop the tower, or in our case, grain legs. We position our units near the AP using an offset bracket.

I guess it all boils down to personal preference.

newcastle wrote:
You still have to plug it into the timing port, right? atop the tower, is my point, not trying too hard to be a hardon. Even if it works at ground level, don't you still have to plug it into the timing port on a unit atop the tower?


Yes, without a syncinjector, you will need to climb the tower.

The parasitic is designed for that situation where you are ok with climbing the tower, but don't want to run another cable.

The only option you really have if you can't climb the tower is something which does Sync over Power, which means SyncInjector+SyncPipe Basic, or the CTM from LMG, or a CMM Micro.

newcastle wrote:
It's a GPS antenna purely, without a graphic user interface or means of remote access, unless you have a server at the tower site to facilitate that kind of connection via a serial link.


If you are connected via the timing port, the AP will show timing status, including number of sats, fix status, and the like, whith the caveat that there's a bug right now with P9 hardware and R8 software where this doesn't work right.

-forrest
(aka forrestc@packetflux.com)
forrestc wrote:
[quote="newcastle":2ogxirm9]You still have to plug it into the timing port, right? atop the tower, is my point, not trying too hard to be a hardon. Even if it works at ground level, don't you still have to plug it into the timing port on a unit atop the tower?


Yes, without a syncinjector, you will need to climb the tower.

The parasitic is designed for that situation where you are ok with climbing the tower, but don't want to run another cable.

The only option you really have if you can't climb the tower is something which does Sync over Power, which means SyncInjector+SyncPipe Basic, or the CTM from LMG, or a CMM Micro.

newcastle wrote:
It's a GPS antenna purely, without a graphic user interface or means of remote access, unless you have a server at the tower site to facilitate that kind of connection via a serial link.


If you are connected via the timing port, the AP will show timing status, including number of sats, fix status, and the like, whith the caveat that there's a bug right now with P9 hardware and R8 software where this doesn't work right.

-forrest
(aka forrestc@packetflux.com)[/quote:2ogxirm9]

My GPS page isn't populated on either the P9s or P10s I have these deployed on.
wifiguy wrote:
My GPS page isn't populated on either the P9s or P10s I have these deployed on.


In order to get the GPS status page populated when using a syncpipe, all of the following have to be true:

1) Rev C or later SyncPipe Deluxe or Parasitic

2) 6p6c Cable which contains at least pins 1,3, and 6 between the timing port on the AP and the 6p6c port on the SyncPipe.

3) AP in timing port timing mode.

4) Release 7.x or earlier, or P10 hardware. P9 hardware running 8.x has an issue where the data is populated, but is corrupt.

-forrest