Important things I should know .

[RadDave]

I have...
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Well, as already pointed out, you have just a basic modem only offering a non-firewall public connection to the internet - I hope that you have turned on the firewall in the Mac OS, i.e. System Preferences -> Security & Privacy -> Firewall.

SO, get ye a router! As suggested, your options are: 1) Checking w/ TW to replace your current modem w/ a 'combo' modem/router or 2) Purchase a 'wireless' router yourself - your modem's ethernet cable will go to the WAN input on the router and then a LAN cable connected to your computer (unless you want a wireless connection).

The router will have its own built-in firewall and offer a personal home network using the DHCP & NAT protocols; plus you can setup a wireless Wi-Fi home network (if so be sure to activate security, such as WPA2) which offers many possibilities. Good luck - Dave

 

[dotdotdot]

^Or just turn on the iMac's firewall?!

 

[MacInWin]

Yes, that would suffice, but if you have the funds, or if TW will give you a true router to replace the modem, that does offer some additional protection. With the modem, you are directly connected to the Internet, with your IP address directly visible. If you had a router, in addition to the firewall, there is some slight added anonymity provided through the DHCP service of the router. (Or at least I've been told that. I'm NOT a network engineer.)

 

[lclev]

lclev, I will disagree with what you said, gently. Most of the pure modems I have seen are just that, a modem. IF, as Raz0rEdge says, it's also a router, then it will have more than one Ethernet port on the back and some sort of DHCP function internally. However, the typical modem I have seen has ONE ethernet port, which is unprotected by any firewall. Now, if your ISP provides a modem/WiFi Router combination, then yes, there is most likely a firewall function. It's dangerous to assume that every device provides that function, however.

I don't disagree. ;D I did however, look up the modem model he has and I edited my post to reflect that the modem does not seem to indicate it has a firewall there for suggesting he needs a router. The install guide is very devoid of information - imaging that. His model seems to be very simple and only offer the one ethernet port.

The one my son has from Time Warner has WiFi and a firewall so the model does make a difference.

But that said, if dotdotdot is concerned a good router with a firewall is in order. Now for the commercial .... I like Cisco/Linksys routers. Just my preference.

Lisa

 

[RadDave]

^Or just turn on the iMac's firewall?!

Hi Dot...... - not sure if you're reacting to my comment on making sure that your Mac OS firewall is turned on w/ you only modem connection to the web, but was wondering about the '^ ?!' symbols -

Not sure if you read the first page of this thread but the discussion involved having a router w/ its own firewall and then whether to turn on the Mac OS X firewall, i.e. having both active @ the same time - a link that I gave in an earlier post was to another thread w/ a similar discussion.

But, if you're not planning on obtaining a router (which I would still strongly recommend), then go into 'System Preferences' and simply turn on your Mac OS firewall, if not already done - attached is a 'screen capture' from my MBPro showing the firewall ON. Let us know if you have other questions - Dave
.

 

[dotdotdot]

I did just turn it on -- can't see buying yet more electronic equipment when I have the "free" firewall.

Also, this entire issue is surprising and a bit alarming to me given that Apple is reputed to be secure and free of anything bad unlike You-Know-Who.

 

[RadDave]

I don't disagree. ;D I did however, look up the modem model he has and I edited my post to reflect that the modem does not seem to indicate it has a firewall there for suggesting he needs a router. The install guide is very devoid of information - imaging that. His model seems to be very simple and only offer the one ethernet port.

The one my son has from Time Warner has WiFi and a firewall so the model does make a difference.

But that said, if dotdotdot is concerned a good router with a firewall is in order. Now for the commercial .... I like Cisco/Linksys routers. Just my preference.

I also looked up that manual and was 'bare bones' and simply a modem stating only an ethernet connection for a Mac OS. My IT son also has TW @ home and tried their 'combo' device and was not happy (he has a much more complicated home network than me, so maybe an issue?) and went back to his Apple router.

When I was on Windows PCs, I started w/ a Linksys router, 802.11 b (a while ago!), then upgraded to Linksys g and to Cisco n - then I switched to Apple last spring and could not get the Cisco router to behave w/ my new iMac - sure I could have figured it out but became frustrated (and my spouse was complaining - which was the most important stimulus - ) - so just went out and bought a Apple Airport Extreme which worked immediately - I miss the browser configuration setup - have to use the Airport Utility, but have been happy w/ my now fourth router - Dave

 

[vansmith]

Also, this entire issue is surprising and a bit alarming to me given that Apple is reputed to be secure and free of anything bad unlike You-Know-Who.

It's good practice to be critical of anything that says "unlike every other product in our category, we have no flaws that you should concern yourself with." Apple devices are no different - they all run software designed by people who make exploitable mistakes. OS X and iOS most certainly fall into this category and it's good practice to remain vigilant while keeping this in mind.

 

[lclev]

Yikes! I regressed to my former Windows self! (Told you we need a 12 step program for former Window-a-holics.)

I should have recommended an Apple AIrport extreme. We have one at work that we use to stream music from an iPad to a soundboard. It also allows the musicians to set their ear bud volume on the soundboard and some other things (not a musician, I just make the network part work.) I found it easy to setup once I got the hang of the Airport Utility.

I will say we bought a second Airport Extreme for our other soundboard - same manufacturer, different model. We had to take the AIrport Extreme back and change to a Linksys router. We called the manufacturer and they told us that for some reason, that model of soundboard would not work with the Airport Extreme. Really strange.

Lisa

 

[RadDave]

I did just turn it on -- can't see buying yet more electronic equipment when I have the "free" firewall.

Also, this entire issue is surprising and a bit alarming to me given that Apple is reputed to be secure and free of anything bad unlike You-Know-Who.

Hi again - LOL! Yes, now that your OS X firewall is ON, you are quite safe, but I'm not sure you saw the last paragraph of one of my earlier posts (quoted below) - a 'wireless' router will allow you to setup a Wi-Fi home network which offers so many options, if you are interested - don't know?

For myself, my wife is on our cabled iMac; I'm in the den @ the moment on my MBPro connected to the internet via Wi-Fi, as I type this post; we both have Wi-Fi iPads which we can use throughout the house (being now retired, I check my email in bed every morning on my iPad for an initial 'flushing out' the junk - ). We have Roku devices in the den (for me) and the main bedroom for my wife (we don't watch the same films) - can stream movies from Amazon & Netflix, music from Pandora, and other 'wireless' options - plus, some of my more recent electronic equipment (i.e. HDTV & Blu-ray player) are Wi-Fi capable - there are many other considerations in a home, including your HVAC & appliances - see the attached pic - home Wi-Fi is really an amazing experience - so think about it? Dave

P.S. also print over the wireless network to either our Canon ink jet or Brother laser printers!

The router will have its own built-in firewall and offer a personal home network using the DHCP & NAT protocols; plus you can setup a wireless Wi-Fi home network (if so be sure to activate security, such as WPA2) which offers many possibilities.

.

 

[dotdotdot]

Hi again - LOL! Yes, now that your OS X firewall is ON, you are quite safe, but I'm not sure you saw the last paragraph of one of my earlier posts (quoted below) - a 'wireless' router will allow you to setup a Wi-Fi home network which offers so many options, if you are interested - don't know?

Only device I have is the iMac, so there is nothing to be gained with WiFi (OK, maybe the extra security). Also, I like the reliability and security of a hard wire link and I believe a wired connection can be faster than a WiFi one.

 

[chas_m]

This is exactly why I say people have a very poor understanding of firewalls and what they do. One is not "perfectly safe" behind one, except from DDOS (denial of service) attacks. It doesn't stop malware, it doesn't stop viruses (for PCs). Let's not give someone a false sense of security.

At the same time, I don't mean to alarm anyone. Being on a Mac, you are automatically protected from most malware through your built-in software, and as you've heard Macs don't have viruses. Barring deliberate actions from you, you're extremely unlikely to get any sort of malware. In the OP's particular case, the software firewall is a good idea, but it's not a panacea for anything. As I stated earlier, having double firewalls can cause problems. It doesn't always, but it can, and they are devilishly difficult to diagnose when they do.

How Firewalls Work - HowStuffWorks

 

[MacInWin]

But, chas_m, he can certainly use two firewalls safely (as I do) and then IF he sees any strange stuff, just turn off the software firewall to see if it's some interaction. It's not hard at all to diagnose, as long as you know you have two firewalls. I've never had any problems and all my systems have three firewalls (one the the modem/router from my ISP, one in the Airport Extreme and the software firewall that I have turned on in all of them--two MBPs, an iMac and a Mini).

 

[chas_m]

Jake, I completely agree with your post -- but in the real world, a LOT of people forget they have the second one turned on after a while, or forget to mention it when reporting the problem. Had way, way, way too many examples of this to ever recommend turning on the software firewall short of situations like the OP's or if one finds oneself in a dodgy Internet cafe in Mos Eisley.

 

[MacInWin]

But I heard the Mos Eisley computer security task force had taken care of all the Internet cafe's. I seem to have heard, distinctly, "These are not the viruses we seek."

 

[chas_m]

That's just the company line from G'eeque Squad, the contractor for the computer security task force, they're a division of Jabba "the Whacken" Hut Corp. Don't trust them.

 

[dotdotdot]

Doesn't an ISP filter some of the bad stuff? I get how the nut behind the keyboard can do stupid things, but I'd like to believe an ISP is proactive in catching something.

 

[lclev]

Doesn't an ISP filter some of the bad stuff? I get how the nut behind the keyboard can do stupid things, but I'd like to believe an ISP is proactive in catching something.

No, not really. Your ISP provides a connection. They provide protection for themselves mostly. In my area the ISP's try to get you to install their anit-malware suite that is "free" and updated by them. Most of those suites are resource hogs and designed for Windows.

Home router/modem firewalls are designed to filter out potential malware and the higher the level they are set at, can provide a stealth mode that prevents your modem being visible to others on the internet.

Truthfully, it can all be a bit confusing and if you are worried, setting the firewall to "on" on your iMac should be adequate.

Lisa

 

[Raz0rEdge]

Doesn't an ISP filter some of the bad stuff? I get how the nut behind the keyboard can do stupid things, but I'd like to believe an ISP is proactive in catching something.

Your ISP might provide SPAM filtering if you use their servers, but beyond that they are just the tunnel through which your packets travel. The idea of Net Neutrality is that the ISPs have little say on WHAT those packets are doing and where they are going.

So, as a consumer of the Internets, we can't demand a keep-your-hands-off attitude from the ISPs and then expect them to protect us from us as well..

 

[ankhseeker]

Many block ports as well.