What is firmware, and why might I need to upgrade it?

Q. What is firmware, and why might I need to upgrade it?
Any consumer electronics device is governed by software that’s seated in
onboard chip memory storage. When you turn on the device, it checks this
memory for what to do and loads the software in that area. This turns the
device on.
This firmware, as it’s referred to, can be updated through a process that’s
specific to each manufacturer. Often you’ll see options in your software configuration
program for checking for firmware upgrades.
Some folks advocate never, ever touching your firmware if you don’t need to.
Indeed, reprogramming your firmware can upset a lot of the logical innards of
your device that you struggled so hard to get right in the first place. In fact,
you might see this advice on a vendor site (like this is from the D-Link site):
“Do not upgrade firmware unless you are having specific problems (“If it ain’t
broke, don’t fix it”). Upgrading firmware will reset the settings to default
which means you will lose all your settings. You cannot use the backup settings
feature and apply it to the newer firmware. Do NOT upgrade firmware
with a wireless connection. You will damage the router.” Although not all
vendor firmware upgrades will reset your settings to default, many do. Be
careful!
Okay, we don’t necessarily disagree with any of that except to say, “Never say
never.” The standards in the wireless arena are changing, particularly in the
802.11a and 802.11g areas. One of the key ways that you can keep current
with these standards is by upgrading your firmware. You will find over time
that your wireless network will fall out of sync with these standards, and
you’ll have to upgrade at some point. When you do so, follow all the manufacturer’s
warnings.
In Chapter 10, we discuss a forthcoming security enhancement for 802.11
LANs called Wi-Fi Protected Access (WPA). Many existing APs and network
adapters will be able to use WPA but only after they’ve had their firmware
upgraded.
Q. Isn’t NAT the same as a firewall?
If you finding networking confusing, you’re not alone. (If it were so easy, we’d
have no market for our books!) One area of a lot of confusion is Network
Address Translation (NAT). And no, NAT is not the same as a firewall. It’s
important to understand the difference, too, to make sure that you set up
your network correctly. Firewalls provide a greater level of security than a
NAT router, and as a result, are generally more expensive than simple routers.
Often you’ll hear the term firewall used to describe a router’s ability to protect
LAN IP addresses from Internet snoopers. But a true firewall actually
goes deeper than this, using SPI. This allows the firewalls to look at each IP
address and domain requesting access to the network; the administrator can
specify certain IP addresses or domain names that are allowed to be let in
while blocking any other attempt to access the LAN. (Sometimes you’ll hear
this called filtering.)
Firewalls can also add another layer of protection through a Virtual Private
Network (VPN). This enables remote access to the private network through
the use of secure logins and authentication. Finally, firewalls can help protect
your family from unsavory content by enabling you to block content from
certain sites.
So firewalls go well beyond NAT, and we highly recommend that you have a
firewall in your home network. Check out Chapter 10 for more information on
firewalls.
Q. How can I find out my IP address?
Well, first off, you have two IP addresses: your public IP address and your private
IP address. There are instances where you need to know one or the
other (or both) of these.
Your private IP address is your IP address on your LAN so that your router
knows where to send traffic in and among LAN devices. If you have a LAN
printer, that device will have its own IP address, as will any network device
on your LAN.
The address that these devices have, however, is rarely the public IP address
(the address is the “Internet phone number” of your network) mostly
because public IP addresses are becoming scarce. Your Internet gateway has
a public IP address for your home. If you want to access a specific device
that’s on your home network but from a public location, you typically have to
enable port forwarding and address that port on your public IP address,
something like 68.129.5.29:80, where 80 is the port.
You can usually find out your wide area network (WAN; public IP address) and
LAN (private IP address) from within your router configuration software. You
might see a Status screen; this is a common place where it shows your present
IP addresses and other key information about your present Internet connection.
If you have Windows 2000 or XP, you can find your computer’s private IP
address by choosing Start➪Run. When the Run dialog box pops up, type cmd
and then click OK. In the window that opens, type ipconfig at the command
prompt and then press Enter. You’ll see your IP address and a few other network
parameters.
This IP address is your internal or private IP address, not the public address
that people on the Internet use to connect to your network. So if you try to
give this to someone (perhaps so that they can connect to your computer to
do some videoconferencing or to connect to a game server that you’re hosting),
it won’t work. You need the public IP address that you’ll find in the configuration
program for your access point/router.
Q. If everything stops working, what can I do?
The long time that it can take to get help from tech support these days actually
does lead a lot of people to read the manual, check out the Web site, and work
hard to debug their present situation. But what happens if you’ve tried everything,
and it’s still a dead connection — and tech support agrees with you?
In these instances, the last resort is to do a reset of the system back to the
factory defaults and literally start over. If you do this, be sure to upgrade
your firmware while you’re at it because it will reset your variables, anyway.
And who knows, the more recent firmware update might resolve some issues
that could be causing the problems.
Resetting your device is considered a pretty drastic action and taken only
after you’ve tried everything else. Make sure that you at least get a tech support
person on the phone to confirm that you have tried everything else and
that a reset makes sense.