Port 631 (IPP Printer sharing) off?

hisara · 10-09-2006, 06:46 AM

NetBarrier X4 shows "udp(4) local port 631 (ipp printer sharing)" in Monitoring>Services. I have in OS X Sharing Preference Pane: Personal File Sharing off and Firewall on (all Allow check boxes off) and Internet Sharing off.

I dont want to share printer. What process causes this and where i can turn it permanately off?

I noticed that NewBarrier shows also 2 rows: "udp(4) 123 (ntp - network time protocol)" ALL the time. Is this normal?

benwiggy · 10-09-2006, 07:31 AM

The Network Time Protocol is probably because you have it set in the Date & Time System Preference to check the time from a network time server.

This is normal!

You don't mention whether Printer Sharing is off in the Sharing preference.

I don't know your setup, and I don't want to seem glib about security, but I doubt you will get anyone intruding through 631 or 123.

hisara · 10-09-2006, 08:11 AM

Printer Sharing is off.

Glib???

Thanks

hisara · 10-16-2006, 02:12 AM

I still have in NetBarrier>Monitoring>Services:

Protocol: UDP(4)
Local Port: 631 (IPP - printer sharing)
Remote Port: (empty)
Remote Address: (empty)
State: (empty).

What process creates this? I want to stop it.

gsahli · 10-16-2006, 08:20 AM

CUPS (process cupsd). You can stop it if you don't want to print.

hisara · 10-18-2006, 03:22 AM

I presume you mean this:
/usr/sbin/cupsd

I added to LittleSnitch rule to deny all connections by cupsd. What default firewall rule allows cupsd to go network?

benwiggy · 10-18-2006, 10:57 AM

CUPS uses the network because it controls printing to printers over TCP/IP.
If you kill the process, you won't be able to print.

This is a standard thing. Why are you so obsessed with closing every port?

You already have the Apple Firewall turned on, and NetBarrier, and LittleSnitch. I think you're going to be ok!

elmak · 09-09-2007, 08:02 PM

CUPS reaches out via UDP port 631. It allows you to print to printers on your network, and for your printer to accept print jobs from other computers on the network (only if you have printer sharing on). If you block the port, you won't be able to print to printers elsewhere on your network.

No one can access your machine via that port because the CUPS process runs in a closed enviroment so it cannot interfere with your files or settings. If you really want to mess around with CUPS, you can configure it here.

Quantumstate · 09-09-2007, 08:57 PM

Yes, it is possible to block all UDP in the firewall. (Options)

10-09-2006, 06:46 AM	#1
hisara Triple-A Player Join Date: Mar 2006 Posts: 212	Port 631 (IPP Printer sharing) off? NetBarrier X4 shows "udp(4) local port 631 (ipp printer sharing)" in Monitoring>Services. I have in OS X Sharing Preference Pane: Personal File Sharing off and Firewall on (all Allow check boxes off) and Internet Sharing off. I dont want to share printer. What process causes this and where i can turn it permanately off? I noticed that NewBarrier shows also 2 rows: "udp(4) 123 (ntp - network time protocol)" ALL the time. Is this normal? Last edited by hisara; 10-09-2006 at 07:00 AM. Reason: Added info

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10-09-2006, 07:31 AM	#2
benwiggy MVP Join Date: Aug 2006 Posts: 2,281	The Network Time Protocol is probably because you have it set in the Date & Time System Preference to check the time from a network time server. This is normal! You don't mention whether Printer Sharing is off in the Sharing preference. I don't know your setup, and I don't want to seem glib about security, but I doubt you will get anyone intruding through 631 or 123.

10-09-2006, 08:11 AM	#3
hisara Triple-A Player Join Date: Mar 2006 Posts: 212	Printer Sharing is off. Glib??? Thanks

10-16-2006, 02:12 AM	#4
hisara Triple-A Player Join Date: Mar 2006 Posts: 212	I still have in NetBarrier>Monitoring>Services: Protocol: UDP(4) Local Port: 631 (IPP - printer sharing) Remote Port: (empty) Remote Address: (empty) State: (empty). What process creates this? I want to stop it.

10-16-2006, 08:20 AM	#5
gsahli MVP Join Date: Apr 2004 Location: Chicago Posts: 1,001	CUPS (process cupsd). You can stop it if you don't want to print.

10-18-2006, 03:22 AM	#6
hisara Triple-A Player Join Date: Mar 2006 Posts: 212	I presume you mean this: /usr/sbin/cupsd I added to LittleSnitch rule to deny all connections by cupsd. What default firewall rule allows cupsd to go network?

10-18-2006, 10:57 AM	#7
benwiggy MVP Join Date: Aug 2006 Posts: 2,281	CUPS uses the network because it controls printing to printers over TCP/IP. If you kill the process, you won't be able to print. This is a standard thing. Why are you so obsessed with closing every port? You already have the Apple Firewall turned on, and NetBarrier, and LittleSnitch. I think you're going to be ok!

09-09-2007, 08:02 PM	#8
elmak Registered User Join Date: Sep 2007 Posts: 1	CUPS reaches out via UDP port 631. It allows you to print to printers on your network, and for your printer to accept print jobs from other computers on the network (only if you have printer sharing on). If you block the port, you won't be able to print to printers elsewhere on your network. No one can access your machine via that port because the CUPS process runs in a closed enviroment so it cannot interfere with your files or settings. If you really want to mess around with CUPS, you can configure it here.

09-09-2007, 08:57 PM	#9
Quantumstate Major Leaguer Join Date: Jan 2007 Location: Seattle, Ecotopia Posts: 405	Yes, it is possible to block all UDP in the firewall. (Options)