[TenTec] Omni VII - I feel like such a n00b...

Jim jdunbar28 at mchsi.com
Sat Dec 8 10:56:25 EST 2007


Duane,

Don't feel bad about IP issues, there is a lot to learn about the explosive
increase of TCP / IP users and the increased amount of devices that are now
entering the INTERNET DOMAINS. (ie; Radios that are TCP / IP
enabled)......Think about it, in the future almost everything that you touch
will have an IP address and be networked........That is just the way things
are GOING.....

Just a few comments, FYI, on the IP addressing (DHCP versus Static IP
assignments).

I provide this information from my experience as a former / recent Wide Area
Network and Data Center Design Engineer at Bell Labs / Lucent Technologies

Keep in mind that there are numerous factors as when DHCP is used versus
static IP assignments on Host Client Machines.

Typically, the use of DHCP servers, either serving up IP addresses from a
windows 2000 server that has DHCP configured or a serving up IP addresses
from a Cisco Router that has DHCP enabled, this is primarily a prevalent
practice so that the valid 192.168.x.x private network blocks can be reused
over and over at each of the client sites (company lans or private
individual client sites).

DHCP is just a temporary convenient method to conserve or slow down or
prolong the time that the remaining available Public IP address classes that
are assigned by the Internet Assigned Network Authority (IANA), are fully
depleted. This is why there is such a focus on the future transition to IPV6
and the move away from the current IPV4 for good.

The problem is that in order to switch over to IPV6 which has basically an
unlimited amount of IP addresses available, will require the BIG GUYS
(CISCO, JUNIPER, ETC) that have all of their big core switches and routers
(their layer 2 / layer 3 switch routers) in all of the Nations Data Centers,
as well as all of the carrier Data Centers (AT&T, SBC, Verizon, etc;) These
major players have to make the first move to switch all of these switches
and routers into IPV6. It cost $$ to do this and also effects every core
switch and router in the industry.

This is not a trivial exercise, it is the equivalent to forcing all TV
STATIONS in the United States to convert over to HDTV and be ONLY HDTV
Capable by a certain deadline. Because not only is this a huge expense on
all of the TV stations to completely change out their Antennas,
Transmitters, and Studio designs to totally digital, it also will require
that every home owner get rid of the analog TVs forever, and if you want to
watch TV you will have to have a HDTV capable system. For the short term,
they will allow folks to keep their old TVS, but this will not last forever.

So, this transition to IPV6 is a similar transition, and that is why there
is no HARD date that the entire Internet will be IPV6.

So, as Gary has indicated, you need to be able to be work with both DHCP as
well as Static IP assignments, as there are many devices out there that are
only able to use STATIC IP assignments manually assigned and will not take a
dynamically assigned address from a DHCP server, because their software or
hardware does not support the entire TCP / IP stack, therefore, some of
these devices out there that are put on you network need a static IP
assigned, a subnet mask assigned, and a default gateway assigned, and that's
it.

Also, even though the RFC 1918 provides series of Class C IP addresses
groups in the valid private IP range from 192.168.0.0 up through
192.168.255.255. This does not mean that all of these IP addresses are
assignable to Hosts. The first IP address in the Class C group is a Network
Address only  and the last IP address is a broadcast IP address only. So
therefore, for an IP Class from 192.168.0.0 to 192.168.0.255, there are only
254 IP addresses assignable to a client workstation 192.168.0.1 up through
192.168.0.254. Again, the first and last IP addresses in the class are only
the network and broadcast addresses.

So therefore, is someone attempted to assign 192.168.0.0 to a client
workstation, this WILL NOT WORK.

Finally, even if you are using a DHCP pool of private addresses on your
local lan, these addresses are NOT Routable on the INTERNET, your gateway
router has to perform Network Address Translation (NAT) for all of the
private IP addresses to a single public address in order to go out to the
internet. You can never send a private IP address (192.168.x.x) out on the
internet.

So, in a nutshell, there are huge complex issues for network design
engineers in the heterogeneous interoperability between thousands of
organizations or users going out to the internet...........

As we move further into the future, this is going to force the amateur radio
operators to become much more intelligent in the use of TCP / IP, DNS,
etc;.....

Have Fun,

Jim
K4PV


-----Original Message-----
From: tentec-bounces at contesting.com [mailto:tentec-bounces at contesting.com]On
Behalf Of Gary Hoffman
Sent: Saturday, December 08, 2007 12:52 AM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] Omni VII - I feel like such a n00b...

Good points.

I always assign my IP addresses statically (having been an ISP for years I'm
a nerd about this) so I don't even notice when devices do or don't have DHCP
capability.  This capability is so pervasive these days that one just
expects it to be available, if not by default.  Just shows...never assume
:)

What I said before still goes....no reason the radio should not accept a
zero there.  One would think it a relatively easy fix.

Better still would be DHCP.  People need that, IMHO, if only as an option.
However, adding DHCP might be more of a significant task.

Gary

----- Original Message -----
From: "Bob Cunnings" <bob.cunnings at gmail.com>
To: "Discussion of Ten-Tec Equipment" <tentec at contesting.com>
Sent: Saturday, December 08, 2007 1:42 AM
Subject: Re: [TenTec] Omni VII - I feel like such a n00b...


> Actually, DHCP isn't involved. The Omni VII ip address is statically
> assigned, by the user, as a member of the class C network behind the
> router. See:
>
> http://rfsquared.com/file_download/180
>
> The user must discover the router's ip address, and then construct an
> appropriate address for the Omni VII, by modifying the last octet. In
> the (unlikely ?) event that the network behind the router isn't the
> typical (private) class C 192.168.1.0 address, this could be a
> problem. Per RFC 1918, the range of private class C network addresses
> is is from 192.168.0.0 to 192.168.255.255 (per RFC 1918) so
> 192.168.0.0, requiring a zero in the 3rd octet, may actually be
> encountered in real life. Apparently the Omni VII doesn't have DHCP
> client functionality...
>
> Bob NW8L
>
> On Dec 7, 2007 10:36 PM, Duane Calvin <ac5aa1 at gmail.com> wrote:
> > Agreed, but the radio is most likely getting assigned an IP via DHCP in
the
> > router, and most folks don't change the default settings.  Then again,
maybe
> > I'm way off on this - I don't have an Omni VII and don't know what is
> > required for the setup other than it's expected to reside behind a
router in
> > the user's environment.
> >
> >         73, Duane
> >
> > Duane Calvin, AC5AA
> > Austin, Texas
> > www.ac5aa.com
> >
> _______________________________________________
> TenTec mailing list
> TenTec at contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
>


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