4. September 2010 by admin.

Internet Protocol version 6 is becoming more and more important as the IPv4 space dwindles away to nothing. The IPv4 space that we’ve all been so comfortable with is … running out. I almost don’t need to say that. The NEW WORLD will be quite a new situation to see. A sight for sore eyes to coin a phrase. Or not? Because everyone is so used to the IP addresses that have been the IPv4 space … the Internet World as it were. NAT has been a big champion for both saving IPv4 space as well as something called “Security by Obscurity”. In other words if you sit behind a NAT to local (RFC 1918) IP Addresses then it’s much harder to find you and explioit or compromise your computer.

IPv6 promises to make that much more difficult. There are a lot of details as to why but I’ll leave that to others to describe. YOU WILL be on IPv6 soon. Wether you choose to or like it or not. Many Cellular Companies are already using it. Which is why I had a question to my suppliers as to IF our gear was IPv6 capable. Not just from the simplest form … but on the ISP Connection level. If our Cellular ISP starts wanting to connect us using IPv6 Addresses can our gear handle that???? I haven’t got the right answer yet. I think it needs to come from higher up.

IPv4 used nice decimal - dotted - addresses. And we studied that for years to learn how to deal with that , including subnetting and superneting and CIDR as it came along. But IPv6 kind of changes the game a bit. A binary bit. A hexadecimal bit.

IPv4 addresses have been 32 bit. IPv6 addresses will be 128 bits. That’s twice the size of the current 64-bit personal computers computing size. Not that this is a problem. It is just a comparison.

IPv6 addresses will be given and discussed in Hexadecimal. Not many people, including some networking technicians are used to discussing things that way. Older programmers and some C and such programmers don’t see this as a problem.

I have been going back to school. Not because the kids have also went back to school after the summer. But because I needed to refresh my knowledge of numbering systems and re-understand hexadecimal.

So I have been going retro … back to the past … or back to the future … however you look at it. I have been playing around with some Altair 8800 and Imsai 8080 simulators. The reason is not purely for geek enjoyment, although the history of Apple Computer Co. and Microsoft Co. (Micro-Soft back then) is interesting, but the going back to the basics - hardware and software - of those simple machines just might make it easier to understand things like Octal and Hexadecimal. They just might be a good and cool and interesting tool to help with getting ready for IPv6. And they have totally been that for me.

Altair 32 Emulator in Windows and the latest Z80pack in Ubuntu Linux - with Altair and Imsai which includes and uses something called “FrontPanel”, are great places to start on such a journey. I didn’t say this was all easy either … but for the geek that wants to go retro, like I did, to freshen up on Hexadecimal (and Binary and Octal) to help them with IPv6 it just might be worthwhile.

Did I just say “Ooh Nix” instead of Unix?

—
Alan Spicer Marine Telecom
http://www.marinetelecom.net and http://www.wifiyacht.net
+1 954-683-3426
communications @ marinetelecom.net

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4. September 2010 by admin.

I thought this was interesting as well … also received via a ham radio email group message. I already knew that sea water made a very good ground plane (counterpoise) or whatever for antenna systems. This becomes very important at HF / SSB Radio frequencies on boats. The ground / counterpoise that is. Anyway here we go…

—
Alan Spicer Marine Telecom
http://www.marinetelecom.net and http://www.wifiyacht.net
+1 954-683-3426
communications @ marinetelecom.net

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4. September 2010 by admin.

I like to give a little bit back to my marine / yachting customers. Many captains and engineers on yachts are very intelligent individuals. I’m a ham radio operator as well as working in marine communications and Internet Systems. I ran across a video on a ham radio related email list today. It was for a Do It Yourself VHF Marine Antenna. I thought that was a novel concept … ham radio operators often make (some) of their own antennas.

Most yachts have an engine room and engineering work spaces. With sufficient tools and such.

So what about a scenario? Now in every day practice your not going to make your own VHF antenna for marine. It’s just not practical. But what if something happened to your VHF antenna and you just had to transmit? What if your whole VHF Radio (or radios?) went bad. Not likely? What if a lightning strike occured?

So could you put yourself and your vessel back on the air? I say yes.

If you kept the appropriate measurements (see the video to follow) around safely somewhere, and some RG58 or better coax cable. Could you make an emergency antenna? I say yes again.

Another thought is … there are often handheld VHF marine radios onboard a vessel. So what’s the antenna connection for  those? I ask that question because you would need to. Is it BNC? Is it SMA? If you ran into a scenario where you had to make a better antenna (for better range) and the only radios that you had working were handheld VHF marine walkie talkies… then that would be what you had to use.

So having the correct adaptors around for the handheld VHF marine radios and the coax cable - some feet of that? maybe a small roll. And the correct connectors (and a soldering iron?) You could make an emergency communications system for your vessel. See the following video:

Now I didn’t make this video. But it seems fairly competent. And it could be used … for an emergency replacement antenna on a vessel or related support craft (work boat) to provide longer range VHF Marine Communications than a handheld walkie talkie could provide.

—
Alan Spicer Marine Telecom
http://www.marinetelecom.net and http://www.wifiyacht.net
+1 954-683-3426
communications @ marinetelecom.net

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