Apple Airport Express + DSP

Re: Apple Airport Express + DSP

The only issue I've had with the Airport Express is that it can't provide DHCP out its ethernet port, which prevents me from using it to create simple networks for system control.
I always set my DSP's IP addresses manually. Never had a problem doing this with the AE. My MBP and iPad get their addresses wirelessly through the DHCP server in the AE.
 
Re: Apple Airport Express + DSP

I really need to learn more about networking ..... Arthur, do you use the Airport Express connected directly to the UX8800? Would you be kind enough to give me a step by step ?
 
Re: Apple Airport Express + DSP

All right, I shouldn't say "prevents". Just "makes it a pain in the ass since I have to deal with every single device and readdress my laptop".

That will obviously take a certain amount of time in a system pieced together every time you use it, but for an owner/operator setting up a production network where all of the devices, including the Airport Express, are in a common network range would only have to be done once. Setting up your laptop to work in that range just for the time you need it is a matter of setting up a different location in your network preferences, also only done once.

Mac
 
Re: Apple Airport Express + DSP

That will obviously take a certain amount of time in a system pieced together every time you use it, but for an owner/operator setting up a production network where all of the devices, including the Airport Express, are in a common network range would only have to be done once. Setting up your laptop to work in that range just for the time you need it is a matter of setting up a different location in your network preferences, also only done once.

Mac

IMHO, static IPs are a nightmare. Maybe in an install situation where nothing will ever change, sure, it might work. But for any gig where a replacement device might need to be brought in, a device would need to be reset, etc, it is a recipe for disaster.

Why?

Because setting a static IP is more than setting the IP, it requires setting the subnet. Sure, everything should be on 255.255.255.0, but will it default to that? Are you going to rely on your guys knowing that at a show when there's an emergency? Are you really going to keep an IP address table handy so you know what to assign that new fancy device to? What if you don't have a list of what's what, and you need to readdress something quickly. Heck, what if you get in a loaner device that is set static and it's not labeled? Now you have to reset the device, check the manual to see what it defaults to, change your computer's static IP to be one in the range of your new static device, change the static device, then change the computer back.

Trust me guys, static IPs are NOT recommended for anything that could change, especially in a time-crunch situation, where the people doing the changing might not have network experience.

Edit: more along the lines of this thread, trying to work around a device that doesn't support DHCP is a waste of time. Throw it out, buy a $50 wireless N router, and call it a day. I do realize there are some devices that have to be static, like Yamaha consoles (I think?). At least the iLive supports DHCP...
 
Re: Apple Airport Express + DSP

Edit: more along the lines of this thread, trying to work around a device that doesn't support DHCP is a waste of time. Throw it out, buy a $50 wireless N router, and call it a day. I do realize there are some devices that have to be static, like Yamaha consoles (I think?). At least the iLive supports DHCP...

Per my original post on this thread, while you can kludge this device to do what you need in an emergency (as long as both devices you are connecting to allow you to set a static IP), but it is NOT the right tool for the job. I can understand living with an annoying workaround when it means you save lots of money, but wireless routers are cheap as chips. You can find working ones lying on street corners. They give them away in Cracker Jack boxes. Why waste your time with a workaround?
 
Re: Apple Airport Express + DSP

Per my original post on this thread, while you can kludge this device to do what you need in an emergency (as long as both devices you are connecting to allow you to set a static IP), but it is NOT the right tool for the job. I can understand living with an annoying workaround when it means you save lots of money, but wireless routers are cheap as chips. You can find working ones lying on street corners. They give them away in Cracker Jack boxes. Why waste your time with a workaround?

Two possible answers-

Brandon already owns it.

Because it's from Apple and anointed by the spooge of Steve Jobs? It just works, right?

/sarcasm & cynicism
 
Re: Apple Airport Express + DSP

lol.

I own one too (I also own a bunch of Linksys WRT54G routers but they are too big to fit in my London rack). I kludged it to get it to work. I cursed it. I cursed it again every time I had to switch back and forth to other networks. I cursed Bill Gates while I was at it I questioned my sanity. I then found a working router lying on the ground in an abandoned building and replaced the Airport Express in my rack. Now the Express again does what it does best: feeding audio from my home network to my living room sound system...
 
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Re: Apple Airport Express + DSP

I really need to learn more about networking ..... Arthur, do you use the Airport Express connected directly to the UX8800? Would you be kind enough to give me a step by step ?
My apologies for the delay in replying, been on the road for the past couple days, this is my first opportunity to respond. I do have my AE with me, but I don't have a UX8800 in front of me, and it's been a while since I've used one, but from memory here's what I think I did to make it work:

1. Set an appropriate IP addresses in the AE. Configuring the AE manually, under the Internet Tab-->TCP/IP I usually set my Airport Express to work well with my home network setup, AE IP address of 192.168.1.2, subnet mask of 255.255.255.0, router address of 192.168.1.1. For Internet tab__>Internet Connection settings I have it set for "Connect Using Ethernet" and for "Connection Sharing" I have it set to "Distribute a range of IP addresses".

2. In the UX8800, I manually set the IP address of the unit, it's important to stay in the same subnet as the AE. So typically for hardware I connect to, I start with 192.168.1.11 or 192.168.1.101 and go up incrementally from there. Subnet mask always 255.255.255.0.

Unless you have a small auto MDX ethernet switch in the rack, you should carry an ethernet crossover cable and likely use it for this connection.

If you're still having trouble, I'll see if I can get my hands on a UX8800 when I get back home. Hope this helps.

Cheers!

Arthur
 
Re: Apple Airport Express + DSP

IMHO, static IPs are a nightmare. Maybe in an install situation where nothing will ever change, sure, it might work. But for any gig where a replacement device might need to be brought in, a device would need to be reset, etc, it is a recipe for disaster.

Why?

Because setting a static IP is more than setting the IP, it requires setting the subnet. Sure, everything should be on 255.255.255.0, but will it default to that? Are you going to rely on your guys knowing that at a show when there's an emergency? Are you really going to keep an IP address table handy so you know what to assign that new fancy device to? What if you don't have a list of what's what, and you need to readdress something quickly. Heck, what if you get in a loaner device that is set static and it's not labeled? Now you have to reset the device, check the manual to see what it defaults to, change your computer's static IP to be one in the range of your new static device, change the static device, then change the computer back.
Point well taken, however if you have your network organized well, and a standard approach for how you set the IP addresses for your DSP's, It shouldn't be that hard to keep things well managed. This implies that every box is labeled with their IP address on the front panel (good practice that I seldom see done), and that your guys have some technical sense to navigate to the appropriate menu to set the IP address. Is it really that hard to do either of these things? Maybe they never set the clock on their VCR's back in the day...I'm sure it's hard to find talent in your neck of the woods...

Trust me guys, static IPs are NOT recommended for anything that could change, especially in a time-crunch situation, where the people doing the changing might not have network experience.
Valid point if your practices are so constantly changing, but honestly, how often do things change that spending an extra 30 seconds to set an IP address is not a good price to pay for a well organized network? Not to nit pick, but when controlling mission critical devices, I'd rather have the security of knowing EXACTLY which box has what IP address, instead of relying on the whims of a DHCP server to determine that for me. This way if an Ethernet cable goes bad, I have eliminated one extra step in troubleshooting the device. This implies good organization in advance of the show. IMHO, DHCP for DSP's or any Professional Audio device is an excuse for a lack of network organization, but that's just me. Ask any network professional worth their pay whether they assign server IP addresses by DHCP? Why should it be any different for mission critical devices in our sound reinforcement systems? Sorry for stepping on any toes here, but I'm a stickler for details, and this is one of them. I can't tell you how many occasions I've come across disorganized networks where it's a pain to get in and do my work.

Edit: more along the lines of this thread, trying to work around a device that doesn't support DHCP is a waste of time. Throw it out, buy a $50 wireless N router, and call it a day. I do realize there are some devices that have to be static, like Yamaha consoles (I think?). At least the iLive supports DHCP...
That's your opinion, I'm sure there are others here who share the same sentiment that the AE is a useful device in my bag, knowing it's limitations. I love the portability, simplicity of setup, cooperates nicely with my home network, and comes in handy when I need a small control network when I'm on the road that my MacBook Pro, iPhone, and iPad connects to effortlessly.
 
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Re: Apple Airport Express + DSP

Valid point if your practices are so constantly changing, but honestly, how often do things change that spending an extra 30 seconds to set an IP address is not a good price to pay for a well organized network? Not to nit pick, but when controlling mission critical devices, I'd rather have the security of knowing EXACTLY which box has what IP address, instead of relying on the whims of a DHCP server to determine that for me. This way if an Ethernet cable goes bad, I have eliminated one extra step in troubleshooting the device. This implies good organization in advance of the show. IMHO, DHCP for DSP's or any Professional Audio device is an excuse for a lack of network organization, but that's just me. Ask any network professional worth their pay whether they assign server IP addresses by DHCP? Why should it be any different for mission critical devices in our sound reinforcement systems? Sorry for stepping on any toes here, but I'm a stickler for details, and this is one of them. I can't tell you how many occasions I've come across disorganized networks where it's a pain to get in and do my work.

+1

DHCP is great until you need to know the IP address of a remote device with an IP assigned by DHCP. Like, say, a headless server or a DSP that you think has fallen off the network. Static IP addresses always work, DHCP works when the server is up and you have other means of discovering a device (broadcast discovery and response, for example).
 
Re: Apple Airport Express + DSP

Sure, static IP always works if you know what you are doing. The reality is that most sound people are not network people, which is where DHCP and ZeroConfig come in as handy tools. What I would be interested in is: How many times does DHCP fail, and in which circumstances? Sure, a broken DHCP server will mess up your network. But other than that? (assuming device discovery is not an issue - that would be a separate subject, but IMHO this should be covered by proper design of the DSP and application)
 
Re: Apple Airport Express + DSP

As has been stated, the Airport express with a single ethernet port cannot provide DHCP over the ethernet port. It can be put into a bridge mode which allows you to connect through to your device in the same way as if you plugged an ethernet cable into the device.

If devices are assigned static IPs, then this will work just fine. If they are not, how were they getting their IPs? From what it sounds like, you plan to just plug in this access point whenever you need to make config changes. It would be the exact same thing as if you would have plugged in your laptop via ethernet without a DHCP server on the network.

For that sort of config, static IPs on your devices makes a huge amount of sense. Assign an address that's unique to each device. Personally, I'd use a class A network so that I can assign devices by type. (subnet 255.0.0.0) Eg, if you use a 10.a.b.c address as your company default, you can assign specific IP addresses to devices based on categories. You can then have 254 of each. Eg, 'a' could represent the company that you installed the gear in, 'b' could represent the type of gear, such as amps, dsp's, printers, etc, and then 'c' represents the number of that device. Your company laptop could then connect to other gear without having to change its IP address when you go to different installs that you put in. Having different company IDs isn't critical, but would be handy if you grabbed a device from one location to take to another in an emergency. It would guarantee no overlap in IP addresses, and devices would still work as expected.
 
Re: Apple Airport Express + DSP

What I would be interested in is: How many times does DHCP fail, and in which circumstances?
When using dhcp you get a lease time for your ip address. Depending on your dhcp server this lease can be anything between nil and weeks.

In some rare circumstances the dhcp client (i.e. your device) will use the old ip address instead of asking for a new one and may therefor become a duplicate address on your currrent network.
 
Re: Apple Airport Express + DSP

Well. As I see it, that would be an incorrect DHCP client implementation. If the lease is about to expire, the client is supposed to renew its lease. What happens if that fails (i.e. no renewal of the existing address and no new IP assignment) falls in the category "DHCP server missing".
 
Re: Apple Airport Express + DSP

Well. As I see it, that would be an incorrect DHCP client implementation. If the lease is about to expire, the client is supposed to renew its lease. What happens if that fails (i.e. no renewal of the existing address and no new IP assignment) falls in the category "DHCP server missing".

A device will start to attempt a lease renewal at 50% of the lease time. So, if you have a lease set at 1 day, in 12 hours, the device will start requesting from the server to renew that lease. If the DHCP server doesn't respond, it will continue to request, in shorter intervals, until which time the lease expires. When that happens, the device will look for other DHCP servers on the network to provide it an IP address. It will continue to use the leased address until it expires, unless manually told to renew. Rebooting a device will trigger a renew of a lease. Some devices will trigger a renew of lease after waking from sleep as well. Many devices will remember their previous DHCP server and try to ask that server first for a renewal, thus maintaining the same IP address. But if it can't find that DHCP server on reboot, it will then accept DHCP offers from any server.

The only real way to end up with network conflicts is to have a device powered up, and then switch the network that it's on without restarting or releasing the existing lease. Not too likely a problem with an audio system setup.
 
Re: Apple Airport Express + DSP

A device will start to attempt a lease renewal at 50% of the lease time. So, if you have a lease set at 1 day, in 12 hours, the device will start requesting from the server to renew that lease. If the DHCP server doesn't respond, it will continue to request, in shorter intervals, until which time the lease expires. When that happens, the device will look for other DHCP servers on the network to provide it an IP address. It will continue to use the leased address until it expires, unless manually told to renew. Rebooting a device will trigger a renew of a lease. Some devices will trigger a renew of lease after waking from sleep as well. Many devices will remember their previous DHCP server and try to ask that server first for a renewal, thus maintaining the same IP address. But if it can't find that DHCP server on reboot, it will then accept DHCP offers from any server.

The only real way to end up with network conflicts is to have a device powered up, and then switch the network that it's on without restarting or releasing the existing lease. Not too likely a problem with an audio system setup.

And you can quite easily set the lease time to be far longer than any show, therefore eliminating any renewal attempts mid-show.