1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
|
Network Working Group Y. Bernet
Request for Comments: 2872 R. Pabbati
Category: Standards Track Microsoft
June 2000
Application and Sub Application Identity Policy Element for
Use with RSVP
Status of this Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2000). All Rights Reserved.
Conventions used in this document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
Abstract
RSVP [RFC 2205] signaling messages typically include policy data
objects, which in turn contain policy elements. Policy elements may
describe user and/or application information, which may be used by
RSVP aware network elements to apply appropriate policy decisions to
a traffic flow. This memo details the usage of policy elements that
provide application information.
1. Overview
RSVP aware network elements may act as policy enforcement points
(PEPs). These work together with policy decision points (PDPs) to
enforce QoS policy. Briefly, PEPs extract policy information from
RSVP signaling requests and compare the information against
information stored by a PDP in a (possibly remotely located) policy
database or directory. A policy decision is made based on the results
of the comparison.
Bernet & Pabbati Standards Track [Page 1]
^L
RFC 2872 Application Identifiers for RSVP June 2000
One type of policy information describes the application on behalf of
which an RSVP signaling request is generated. When application policy
information is available, network administrators are able to manage
QoS based on application type. So, for example, a network
administrator may establish a policy that prioritizes known mission-
critical applications over games.
This memo describes a structure for a policy element that can be used
to identify application traffic flows. The policy element includes a
number of attributes, one of which is a policy locator. This policy
locator includes the following hierarchically ordered sub-elements
(in descending levels of hierarchy):
1. identifier that uniquely identifies the application vendor
2. identifier of the application
3. version number of the application
4. sub-application identifier
An arbitrary number of sub-application identifiers may be included in
the policy locator. An example of such an identifier is 'print
transaction'.
This memo specifies the structure of the application policy element
and proposes keywords for the sub-elements at each level of the
hierarchy. It does not enumerate specific values for the sub-
elements: such an enumeration is beyond the scope of this memo.
2. Simple Application Identity Policy Element Structure
General application identity policy elements are defined in
[RFC2752]. These are policy elements with a P-type of AUTH_APP.
Following the policy element header is a list of authentication
attributes.
The first authentication attribute is of the A-type POLICY_LOCATOR.
The sub-type of the POLICY_LOCATOR attribute is of type ASCII_DN
[RFC1779] or UNICODE_DN. The actual attribute data is formatted as an
X.500 distinguished name (DN), representing a globally unique
identifier, the application, version number and sub-application in a
hierarchical structure. The POLICY_LOCATOR attribute contains
keywords as described in section 2. For further details on the format
of the POLICY_LOCATOR attribute, see [RFC2752].
The second authentication attribute is of the A-type CREDENTIAL. The
sub-type of the CREDENTIAL attribute is of type ASCII_ID or
UNICODE_ID. The actual attribute data is an ASCII or Unicode string
representing the application name. This structure is illustrated in
the following diagram:
Bernet & Pabbati Standards Track [Page 2]
^L
RFC 2872 Application Identifiers for RSVP June 2000
0 1 2 3
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PE Length (8) | P-type = AUTH_APP |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Attribute Length | A-type = | Sub-type = |
| | POLICY_LOCATOR| ASCII_DN |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Application policy locator attribute data in X.500 DN format |
| (see below) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Attribute Length | A-type = | Sub-type = |
| | CREDENTIAL | ASCII_ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Application name as ASCII string |
| (e.g. SAP.EXE) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The following keywords are recommended although others MAY be used:
Key Attribute
--------------
GUID Globally Unique Identifier (optional)
APP Application Name
VER Application Version Number
SAPP Sub Application (optional)
The following are examples of conformant policy locators:
"APP=SAP, VER=1.1, SAPP=Print"
"GUID=http://www.microsoft.com/apps, APP=MyApplication, VER=1.2.3"
The APP, VER and SAPP attributes SHOULD describe the application to a
human reader in as unique and unambiguous a way as possible. The GUID
attribute MAY be used when absolute uniqueness of application
identification is required and its contents MUST be an identifier
from a globally-unique source (e.g. domain names as assigned by the
corresponding registration authorities). Note that publication of the
chosen identifiers in a suitable format is strongly encouraged.
Bernet & Pabbati Standards Track [Page 3]
^L
RFC 2872 Application Identifiers for RSVP June 2000
3. Security Considerations
The proposed simple policy element does not guarantee that element is
indeed associated with the application it claims to be associated
with. In order to provide such guarantees, it is necessary to sign
applications. Signed application policy elements may be proposed at a
future date. Note that, typically, the application policy element
will be included in an RSVP message with an encrypted and
authenticated user policy element. A level of security is provided by
trusting the application policy element only if the user policy
element is trusted.
All RSVP integrity considerations apply to the message containing the
application policy element.
4. References
[RFC2205] Braden, R., Zhang, L., Berson, L., Herzog, S. and S. Jamin,
"Resource Reservation Protocol (RSVP) - Version 1
Functional Specification", RFC 2205, September 1997.
[RFC1779] Kille, S., "A String Representation of Distinguished
Names", RFC 1779, March 1995.
[RFC2752] Yadav, S., Yavatkar, R., Pabbati, R,. Ford, P., Moore, T.
and S. Herzog, "Identity Representation for RSVP", RFC
2752, January 2000.
[ASCII] Coded Character Set -- 7-Bit American Standard Code for
Information Interchange, ANSI X3.4-1986.
[UNICODE] The Unicode Consortium, "The Unicode Standard, Version
2.0", Addison-Wesley, Reading, MA, 1996.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
5. Acknowledgments
Thanks to Tim Moore, Shai Mohaban, Andrew Smith, Ulrich Homann and
other contributors to the IETF's RAP WG for their input.
Bernet & Pabbati Standards Track [Page 4]
^L
RFC 2872 Application Identifiers for RSVP June 2000
6. Authors' Addresses
Yoram Bernet
Microsoft
One Microsoft Way
Redmond, WA 98052
Phone: (425) 936-9568
EMail: yoramb@microsoft.com
Ramesh Pabbati
One Microsoft Way
Redmond, WA 98052
EMail: rameshpa@microsoft.com
Bernet & Pabbati Standards Track [Page 5]
^L
RFC 2872 Application Identifiers for RSVP June 2000
7. Full Copyright Statement
Copyright (C) The Internet Society (2000). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
Bernet & Pabbati Standards Track [Page 6]
^L
|