RE: the future of SNMP

"Harrington, David" <[email protected]> Mon, 3 Mar 2003 12:11:58 -0500
Newsgroups gmane.ietf.eos
Message-ID <6D745637A7E0F94DA070743C55CDA9BA489420@NHROCMBX1.ets.enterasys.com>
This is a multi-part message in MIME format.

------_=_NextPart_001_01C2E1A7.FFB2A918
Content-Type: text/plain;
	charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable

Hi,
=20
I guess this as good a place as any to jump into this thread.
=20
#1 For any solution to work effectively, it will need to be supported by =
both the agent and the manager. Fixing it on one side only is not an =
option.=20
=20
#2 It isn't enough to deliver a large blob of data to an NMS; the NMS =
needs to be able to break it out and process it to display and/or =
convert the raw data into information to make the blob of data =
meaningful to an operator. Without that step it is not a useful =
solution.
=20
#3 using another protocol to transport gathered data requires defining =
some mappings to coordinate that usage. It is not as simple as defining =
a mib and then just saying "send it over FTP". What are the possible =
error conditions that could occur, and how should they be handled? There =
have been earlier attempts to send file of gathered data, such as =
RFC2513, and these have not been widely deployed to my knowledge. I =
would assume that if this design brought great beneift to the SNMP =
community, the approach would have been extended for use in other =
scenrios. Do we know why this never gained much acceptance?
=20
#4 As Juergen pointed out, the security mapping between FTP and SNMPv3 =
will be non-trivial. As a vendor, it is difficult for me to convince a =
customer they should buy our products because we have SNMPv3-strength =
security and then suggest they should use a non-secure protocol like FTP =
to ship bulk data. Even if the file could be transported over SSH or SSL =
or a VPN or IPSec, no mappings have been proposed about how to do that =
in a standardized manner, or what rules need to be followed to balance =
the security between the two. Which security precautions must be =
follwoed sending bulk responses to a noAuthNoPriv request? which are =
acceptable for an authPriv response? Can they be mixed into the same =
buffer?
=20
#5 Even if the file can be transported securely using the correct =
message security level, a file-based transfer does not have =
user-specific access control like VACM. I haven't read the mib recently; =
have mechanisms been defined for coexistence with VACM?=20
=20
#6 As Juergen pointed out, adding new protocol additions may require =
nothing more than a recompile, because many agents and applications use =
a toolkit and if the toolkit has the extra functionality the agent and =
manager will get it by default. However, I will point out that #2 still =
applies. Even if I can add a protocol extension with no work, I still =
need to modify my code to take advantage of the feature. For an NMS, =
this will include probing to determine whether the functionality is =
supported by different agents. If the SNMP stack provides the feature if =
a developer calls the appropriate API, then the developers need to be =
educated about the relative benefits of the new solution so they will =
call the new API rather than just continuing to call the getNext() API =
for all devices. It is easier to just call the same API for all tables =
rather than having to test and debug conditional branches of code. I am =
not convinced that GetBulk has seen wide usage by major NMS vendors yet, =
for similar reasons.=20
=20
dbh
=20
 -----Original Message-----
From: Wes Hardaker [mailto:[email protected]]
Sent: Friday, February 28, 2003 10:43 AM
To: B. Levin
Cc: Glenn Waters; [email protected]
Subject: Re: the future of SNMP



>>>>> On Fri, 28 Feb 2003 07:00:45 -0800 (PST), "B. Levin" =
<[email protected]> said:

B> the MIB solution that I proposed could be implemented
B> (at the NMS side) even on a 10 yr antique NMS.

I'm confused at why there is an argument over what the NMS could
support.  That is hardly what I think needs to be optimized for in
this case (certainly it's impacted, but I'm much more concerned about
the 10000 agents that it's speaking with than the 1 NMS box).

--
Wes Hardaker
Network Associates Laboratories




------_=_NextPart_001_01C2E1A7.FFB2A918
Content-Type: text/html;
	charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META HTTP-EQUIV=3D"Content-Type" CONTENT=3D"text/html; =
charset=3Diso-8859-1">
<TITLE>Re: the future of SNMP</TITLE>

<META content=3D"MSHTML 6.00.2800.1106" name=3DGENERATOR></HEAD>
<BODY>
<DIV><SPAN class=3D939301716-03032003><FONT face=3DArial color=3D#0000ff =

size=3D2>Hi,</FONT></SPAN></DIV>
<DIV><SPAN class=3D939301716-03032003><FONT face=3DArial color=3D#0000ff =

size=3D2></FONT></SPAN>&nbsp;</DIV>
<DIV><SPAN class=3D939301716-03032003><FONT face=3DArial color=3D#0000ff =
size=3D2>I=20
guess this as good a place as any to jump into this =
thread.</FONT></SPAN></DIV>
<DIV><SPAN class=3D939301716-03032003><FONT face=3DArial color=3D#0000ff =

size=3D2></FONT></SPAN>&nbsp;</DIV>
<DIV><SPAN class=3D939301716-03032003><FONT face=3DArial color=3D#0000ff =
size=3D2>#1 For=20
any solution to work effectively, it will need to be supported by both =
the agent=20
and the manager. Fixing it on one side only is not an option.=20
</FONT></SPAN></DIV>
<DIV><SPAN class=3D939301716-03032003><FONT face=3DArial color=3D#0000ff =

size=3D2></FONT></SPAN>&nbsp;</DIV>
<DIV><SPAN class=3D939301716-03032003><FONT face=3DArial color=3D#0000ff =
size=3D2>#2 It=20
isn't enough to deliver a large blob of data to an NMS; the NMS needs to =
be able=20
to break it out and process it to display and/or convert the raw data =
into=20
information to make the blob of data meaningful to an operator. Without =
that=20
step it is not a useful solution.</FONT></SPAN></DIV>
<DIV><SPAN class=3D939301716-03032003><FONT face=3DArial color=3D#0000ff =

size=3D2></FONT></SPAN>&nbsp;</DIV>
<DIV><SPAN class=3D939301716-03032003><FONT face=3DArial color=3D#0000ff =
size=3D2>#3=20
using another protocol to transport gathered data requires defining some =

mappings to coordinate that usage. It is not as simple as defining a mib =
and=20
then just saying "send it over FTP". What are the possible error =
conditions that=20
could occur, and how should they be handled? There have been earlier =
attempts to=20
send file of gathered data, such as RFC2513, and these have not been =
widely=20
deployed to my knowledge. I would assume that if this design brought =
great=20
beneift to the SNMP community, the approach would have been extended for =
use in=20
other scenrios. Do we know why this never gained much=20
acceptance?</FONT></SPAN></DIV>
<DIV><SPAN class=3D939301716-03032003><FONT face=3DArial color=3D#0000ff =

size=3D2></FONT></SPAN>&nbsp;</DIV>
<DIV><SPAN class=3D939301716-03032003><FONT face=3DArial color=3D#0000ff =
size=3D2>#4 As=20
Juergen pointed out, the security mapping between FTP and SNMPv3 will be =

non-trivial. As a vendor, it is difficult for me to convince a customer =
they=20
should buy our products because we have SNMPv3-strength security and =
then=20
suggest they should use a non-secure protocol like FTP to ship bulk =
data. Even=20
if the file could be transported over SSH or SSL or a VPN or IPSec, no =
mappings=20
have been proposed about how to do that in a standardized manner, or =
what rules=20
need to be followed to balance the security between the two. Which =
security=20
precautions must be follwoed&nbsp;sending bulk responses to a =
noAuthNoPriv=20
request? which are acceptable for an authPriv response? Can they be =
mixed into=20
the same buffer?</FONT></SPAN></DIV>
<DIV><SPAN class=3D939301716-03032003><FONT face=3DArial color=3D#0000ff =

size=3D2></FONT></SPAN>&nbsp;</DIV>
<DIV><SPAN class=3D939301716-03032003><FONT face=3DArial color=3D#0000ff =
size=3D2>#5=20
Even if the file can be transported securely using the correct message =
security=20
level, a file-based transfer does not have user-specific access control =
like=20
VACM. I haven't read the mib recently; have&nbsp;mechanisms been=20
defined&nbsp;for coexistence with VACM?&nbsp;</FONT></SPAN></DIV>
<DIV><SPAN class=3D939301716-03032003><FONT face=3DArial color=3D#0000ff =

size=3D2></FONT></SPAN>&nbsp;</DIV>
<DIV><SPAN class=3D939301716-03032003><FONT face=3DArial color=3D#0000ff =
size=3D2>#6 As=20
Juergen pointed out, adding new protocol additions may require nothing =
more than=20
a recompile, because many agents and applications use a toolkit and if =
the=20
toolkit has the extra functionality the agent and manager will get it by =

default. However, I will point out that #2 still applies. Even if I can =
add a=20
protocol extension with no work, I still need to modify my code to take=20
advantage of the feature. For an NMS, this will include probing to =
determine=20
whether the functionality is supported by different agents. If the SNMP =
stack=20
provides the feature if a developer calls the appropriate API, then the=20
developers need to be educated about the relative benefits of the new =
solution=20
so they will call the new API rather than just continuing to call the =
getNext()=20
API for all devices.&nbsp;It is easier to just call the same API for all =
tables=20
rather than having to test and debug conditional branches of code. I am =
not=20
convinced that GetBulk has seen wide usage by major NMS vendors yet, for =
similar=20
reasons. </FONT></SPAN></DIV>
<DIV><SPAN class=3D939301716-03032003><FONT face=3DArial color=3D#0000ff =

size=3D2></FONT></SPAN>&nbsp;</DIV>
<DIV><SPAN class=3D939301716-03032003><FONT face=3DArial color=3D#0000ff =

size=3D2>dbh</FONT></SPAN></DIV>
<DIV><SPAN class=3D939301716-03032003></SPAN><FONT face=3DTahoma><FONT =
size=3D2><SPAN=20
class=3D939301716-03032003><FONT face=3DArial=20
color=3D#0000ff>&nbsp;</FONT></SPAN></FONT></FONT></DIV>
<DIV><FONT face=3DTahoma><FONT size=3D2><SPAN=20
class=3D939301716-03032003>&nbsp;</SPAN>-----Original =
Message-----<BR><B>From:</B>=20
Wes Hardaker [mailto:[email protected]]<BR><B>Sent:</B> Friday, =
February 28,=20
2003 10:43 AM<BR><B>To:</B> B. Levin<BR><B>Cc:</B> Glenn Waters;=20
[email protected]<BR><B>Subject:</B> Re: the future of=20
SNMP<BR><BR></DIV></FONT></FONT>
<BLOCKQUOTE dir=3Dltr=20
style=3D"PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px =
solid; MARGIN-RIGHT: 0px"><!-- Converted from text/plain format -->
  <P><FONT size=3D2>&gt;&gt;&gt;&gt;&gt; On Fri, 28 Feb 2003 07:00:45 =
-0800 (PST),=20
  "B. Levin" &lt;[email protected]&gt; said:<BR><BR>B&gt; the MIB =
solution=20
  that I proposed could be implemented<BR>B&gt; (at the NMS side) even =
on a 10=20
  yr antique NMS.<BR><BR>I'm confused at why there is an argument over =
what the=20
  NMS could<BR>support.&nbsp; That is hardly what I think needs to be =
optimized=20
  for in<BR>this case (certainly it's impacted, but I'm much more =
concerned=20
  about<BR>the 10000 agents that it's speaking with than the 1 NMS=20
  box).<BR><BR>--<BR>Wes Hardaker<BR>Network Associates=20
  Laboratories<BR><BR></FONT></P></BLOCKQUOTE></BODY></HTML>

------_=_NextPart_001_01C2E1A7.FFB2A918--