Printing via TCP/IP... outbound ports

[Patrick Fogarty]

I want change the outbound ports for printing using a 'Standard TCP/IP Port'
in LPR mode on my machine.

To my knowledge, the 'Standard TCP/IP Port' is implemented 'in the spirit'
of the LPR spec, but does not necessarily adhere to it. Of specific
interest, among other things, is the outbound ports used by the machine
sending a print-job to the printer/server.

According to RFC 1179
(http://support.microsoft.com/default.aspx?scid=kb;en-us;124734) the
outbound ports should be 721-731. From what I have read it appears that,
during the days of Windows 2000, a solution was manufactured for some
limitations in RFC 1179
(http://support.microsoft.com/default.aspx?scid=kb;en-us;179156). It also
appears that Microsoft has chosen, with XP, not to try to adhere to the RFC
and implement this change as the norm.

My problem with this is that the outbound port range appears not to be
reasonably finite. From my reading the source rules are merely that the
port can be anything above 1024. I need something much smaller for the
purposes of defining secure firewall rules, hence the request for a way to
go back to the LPR spec.

So here are my questions:
1- what are the allowable outbound ports for 'Standard TCP/IP Port' out of
the box?
2- can the range be confined or set to something completely different, i.e.
721-731?



- Patrick

 

[xe77]

You really should close ports above 1024 anyways because
Windows uses ports 1024 to 4999 as the ephemeral port
range and is need to allow applications to return
communication to the clients, so sending from this range
is OK.

 

[Patrick Fogarty]

While I agree with you on this, my reasons for this request are more
specific.

I am working with the RC2 of SP2 for XP. There are problems with
hardware-based print servers and no one is getting any kind of response out
of Microsoft in the beta newsgroups. This has been going on since the beta.
So I'm tackling this one myself. After monitoring all the traffic, I have a
theory but I need to tie the client down to a reasonably finite number of
ports to prove it.


- Patrick



| You really should close ports above 1024 anyways because
| Windows uses ports 1024 to 4999 as the ephemeral port
| range and is need to allow applications to return
| communication to the clients, so sending from this range
| is OK.
|
|
| >-----Original Message-----
| >I want change the outbound ports for printing using
| a 'Standard TCP/IP Port'
| >in LPR mode on my machine.
| >
| >To my knowledge, the 'Standard TCP/IP Port' is
| implemented 'in the spirit'
| >of the LPR spec, but does not necessarily adhere to it.
| Of specific
| >interest, among other things, is the outbound ports used
| by the machine
| >sending a print-job to the printer/server.
| >
| >According to RFC 1179
| >(http://support.microsoft.com/default.aspx?scid=kb;en-
| us;124734) the
| >outbound ports should be 721-731. From what I have read
| it appears that,
| >during the days of Windows 2000, a solution was
| manufactured for some
| >limitations in RFC 1179
| >(http://support.microsoft.com/default.aspx?scid=kb;en-
| us;179156). It also
| >appears that Microsoft has chosen, with XP, not to try to
| adhere to the RFC
| >and implement this change as the norm.
| >
| >My problem with this is that the outbound port range
| appears not to be
| >reasonably finite. From my reading the source rules are
| merely that the
| >port can be anything above 1024. I need something much
| smaller for the
| >purposes of defining secure firewall rules, hence the
| request for a way to
| >go back to the LPR spec.
| >
| >So here are my questions:
| >1- what are the allowable outbound ports for 'Standard
| TCP/IP Port' out of
| >the box?
| >2- can the range be confined or set to something
| completely different, i.e.
| >721-731?
| >
| >
| >
| >- Patrick
| >
| >
| >.
| >