One document matched: draft-ietf-rap-cops-ds-00.txt
COPS Usage for Differentiated Services August 1998
Network Working Group Francis Reichmeyer
Internet Draft Kwok Chan
Draft-ietf-RAP-COPS-DS-00.txt Bay Networks, Inc.
Expiration Date: January 1999 David Durham
Raj Yavatkar
Intel
Silvano Gai
Keith McCloghrie
Cisco Systems, Inc.
Shai Herzog
IPHighway
August 1998
COPS Usage for Differentiated Services
Status of this Memo
This document is an Internet-Draft. Internet-Drafts are working
documents of the Internet Engineering Task Force (IETF), its areas,
and its working groups. Note that other groups may also distribute
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To learn the current status of any Internet-Draft, please check the
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ftp.isi.edu (US West Coast).
Abstract
There is a clear need for relatively simple and coarse methods of
providing differentiated classes of service for Internet traffic, to
support various types of services, and specific business
requirements. The IETF has chartered the Differentiated Service WG to
define the differentiated services architecture and a common language
for differentiated services.
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COPS Usage for Differentiated Services August 1998
In parallel, the IETF RSVP Admission Policy (RAP) WG has defined the
COPS (Common Open Policy Service) protocol [COPS].
This document describes enhancements to the Common Open Policy
Service (COPS) protocol to support policy services in a
Differentiated Services (diff serv) environment. Further
modifications to COPS for diff serv may be proposed in the future,
but what is presented here is thought to be the minimum necessary
additions.
Table of contents
1. Terminology ......................................................3
2. Introduction ..........................Error! Bookmark not defined.
2.1 Basic Model...................................................6
3. The definition of the Policy Tree ................................7
3.1 Description of the Policy Tree................................8
3.2 Operations Supported On a PI..................................8
3.3 An example of a PIB...........................................8
4. COPS Diff Serv Client Data ......................................10
4.1 Policy Identifier (PID)......................................11
4.2 XDR Encoded Policy Instance Data (XPD).......................11
4.3 Diff Serv Decision Data......................................12
4.4 Diff Serv Request Data.......................................12
4.5 Diff Serv Report Data........................................12
4.5.1 Commit Data .............................................13
4.5.2 No Commit Data ..........................................13
4.5.3 Accounting Data .........................................13
5. Message Content .................................................13
5.1 Request (REQ) PEP -> PDP...................................13
5.2 Decision (DEC) PDP -> PEP..................................14
5.3 Report State (RPT) PEP -> PDP..............................15
6. Common Operation ................................................15
7. Fault Tolerance .................................................17
8. Security ........................................................17
9. References ......................................................17
10. Author Information .............................................18
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1. Terminology
o ACL: Access Control List.
o COPS (Common Open Policy Service): client/server model for
supporting policy control [COPS];
o Instance Identifier: one or more of the PC attributes the values of
which are used as part of the identification of a PI.
o Object: this term is used in the same sense as in COPS
specification. An object is identified by its C-num and C-type.
o PC (Policy Class): a type of policy data item. In object oriented
terminology this is equivalent to a class. It inherits from PC. A
PC defines a vector of attributes. Each attribute has a syntax type
that is either primitive or refined. It also overrides the READ and
WRITE methods and defines new error sub-codes.
o PI (Policy Instance): an instance of a PC. Potentially there are
multiple instances of the same PC. The value of a PI consist of a
vector of values, one value for each attribute in the PC's vector
of attributes.
o PDP (Policy Decision Point): a network entity where policy
decisions are made
o PEP (Policy Enforcement Point): network device where policy
decisions are enforced.
o PIB (Policy Information Base): policy objects are accessed via a
virtual information store, termed the Policy Information Base or
PIB. Objects in the PIB are defined using Abstract Syntax Notation
One (ASN.1) [ASN1].
o PID (Policy IDentifier): the name which identifies a particular PI
or PC. It has a hierarchical structure of the form 1.3.4.2.7, where
the first part identifies the PC (i.e., 1.3.4) and the last part is
the value of the PII (Policy Instance Identifier), which identifies
the instance (i.e. 2.7). The PII is null in the case of a PC.
o XPD: XDR Encoded Policy Instance Data.
2. Introduction
The Common Open Policy Service (COPS) protocol is a query response
protocol used to exchange policy information between a network policy
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server and a set of clients [COPS]. COPS is being developed within
the RSVP Admission Policy Working Group (RAP WG) of the IETF,
primarily for use as a mechanism for providing policy-based admission
control over requests for network resources [RAP].
The underlying assumption in the RAP framework is that applications
or endsystems use the RSVP [RSVP] signaling protocol to communicate
Integrated Services (int serv) reservation requests to the network
nodes along the path of a flow. These reservation requests carry
necessary flow specifications and requests for a flow to receive one
of the defined Integrated Services, Controlled Load or Guaranteed. In
the int serv model, the RSVP messages themselves contain all the
necessary information needed at the networking device to classify and
service the flow [RSVP]. This information includes the session
identifier (source and destination addresses, port numbers, and
transmission protocol), flowspec token bucket parameters, and
requested service.
As shown I Figure 1, the network device contacts a policy decision
point (PDP) to make the policy-based admission control decision.
Then, the policy server (PDP) is simply required to return a
Decision, such as "accept" and the network device acts as a policy
enforcement point (PEP) and uses the session information and intserv
srvice parameters to classify and service the packets belonging to
the flow.
(router, switch) policy server
.
_ ---------------- ________ --------______
| | | | ______
.
| Network Node | | |
.
| ----- ___ | | |
| | | | | |
.
| | PEP |<-----|------->| PDP |
.
| |_____| | |_____ |
.
| ----- | | |
.
|________________| | |
---------------- --------
Figure 1: Under the RAP framework, network elements such as a
router or a switch contact the PDP for policy-based admission control
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when a resource reservation request is received.
Providing policy services in a diff serv environment requires some
different assumptions about the admission control mechanisms used in
the network. First, there may be no explicit signaling from sources
of traffic requesting a particular service as in the case of an
intserv network. Second, requests for allocation of resources to
differentiated services may arrive at the policy server from entities
other than a PEP. Examples of such sources include attached users
requesting network services via a web interface into a central
management application, or H.323 servers requesting resources on
behalf of a user for a video conferencing application. Requests of
this sort require some policy decision to be made to ensure the
requesting user/application has permission to use the requested
services and that the resources are available. Once the decision is
made, the PDP must configure one or more PEPs to provision necessary
resources for services requested. In addition, the PDP may also pass
to the PEP provisioning decisions about resources related to flows of
a more static nature, such as long-term SLAs established across
boundaries of adjacent ISP networks.
In summary, the interaction between the PDP and PEP is different in
at least two respects from that in the case of the intserv
environment. First, the resource provisioning requests may originate
at places other than a PEP. Second, once the PDP makes a policy
decision to allocate resources for a service class or a flow
aggregate, it must pass on the sufficient information (such as packet
classification filters, traffic shaper parameters) to the PEPs so
that PEPs can implement policy decisions. This draft describes the
usage of the COPS protocol for communicating this information between
diff serv clients (PEPs) and the policy servers.
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2.1 Basic Model
Figure 2 shows a sample network configuration for a diffserv
environment. Edge routers and boundary routers are located at the
boundary of diffserv domains as described in [draft-nichols-diff-
serv-arch-00.txt]. The BB is responsible for admission control
functions and resource provisioning. In the COPS model, the PDP is
part of the bandwidth broker that manages resources within a diffserv
domain. Both edge routers and boundary routers act as PEPs and
communicate with BBs using COPS for exchange of policy information.
The internal organization of the BB and policy functionality may
vary: the policy server and BB may be separate entities in which case
the BB, upon receiving COPS messages from the PEP, consults the
policy server to make its decision.
---- ----
| BB | | BB |
| | | |
_---- ----
^ ^
| /
| /
| |
.
/ Stub \ / Transit \ / Stub \
.
/ Network \ / Network \ / Network \
|---| | |---| |---| |---| |---| | |---|
|Tx |-| |ER1|---|BR1| |BR2|---|ER2| |-|Rx |
|---| | |-- | |---| |---| |---| | |---|
\ / \ / \ /
\ / \ / \ /
Figure 2: A sample Network Configuration in which
Edge Routers (ER) and Boundary routers (BR) in the stub and transit
networks communicate with the corresponding bandwidth brokers in
their domain.
To allow for use of COPS for diff-serv specific communication and to
distinuish diff-serv specific communication from other uses of COPS,
we have added a new client type to COPS (client type = DiffServ
client). In an environment where a stub network uses intserv/RSVP
signaling for admission control and uses diffserv-based policy server
for managing resources to a transit network, use of two different
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COPS Usage for Differentiated Services August 1998
client types (RSVP vs diffserv) may require a method that correlates
the two admission control decision. The issue of combining int serv
and diff serv to provide an end-to-end QoS solution is currently
being studied [E2E]. Also, the RSVP WG is currently planning on
addressing the use of RSVP within the differentiated services QoS
model.
3. The definition of the Policy Tree
This section defines data format for the diff serv client specific
information carried in the Decision, Request ClientSI, and Report
ClientSI objects. Diff serv client specific data may be defined for
the other objects in the future.
The policy tree is based on SMI and MIBs. COPS for RSVP does not need
a policy tree, since the information exchanged has a simple format.
However, the COPS protocol does not preclude the use of data,
represented in such a way, with RSVP. COPS for DiffServ needs much
more structure, since it needs to represent policies, mappings, ACLs,
interfaces etc.
The policy tree is structured in the following way:
-------+-------+----------+---PC--+--PI
| | | +--PI
| | +---PC-----PI
| +---PC--+--PI
| | +--PI
| | +--PI
| | +--PI
| | +--PI
| +---PC-----PI
+---PC---PI
Figure 1: Example of a Policy Tree
PIs (Policy Instances) and s
PC (Policy Classes) have names (PIDs:
Policy Identifiers). Names have a hierarchical structure of the form
1.3.4.2.7, where the first part identifies the PC (e.g., 1.3.4) and
the last part identifies the instance (e.g. 2.7).
The policy tree names all the policy data classes and instances and
this creates a common view of the policy organization between the
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client (PEP) and the server (PDP). Therefore, when the PEP receives
data from the PDP, the data itself specifies what a PEP is supposed
to do with the data. The current granularity of access, i.e., the
atomicity of replacement, is proposed as a vector of values.
Note that the PCs/PIs in the above diagram are each a vector of
values. This proposal is that the hierarchy of PCs/PIs is for benefit
of human understanding, not for programmatic understanding, or
inheritance.
3.1 Description of the Policy Tree
The Policy Tree is described using SMI and PIBs. SMI and PIBs are
defined based on the ASN.1 data definition language [ASN1]. This does
not imply that the representation of the policy information on the
wire must follow ASN.1: on the contrary, the proposal it to follow
COPS conventions and to define a new objects (XDR Encoded Policy
Instance Data, see Section 4.2) which contains an XDR encoding. XDR
is a standard [RFC1832] for the description and encoding of data.
3.2 Operations Supported On a PI
The following operations are supported on a PI:
o Install - creates a new instance of a PC, i.e. a new PI, or
modifies an existing instance. The instance is automatically
enabled. Parameters to this operation are a PID (see Section 4.1)
and an "XPD (XDR encoded policy instance Data)" containing the
value to assign to the new PI see (Section 4.2). The XPD specifies
all the attributes of the new PI.
o Delete - This operation is used to delete an instance of a PC. The
parameter is a PID (see Section 4.1).
o Enable. This operation is used to enable a PI.
o Disable. This operation is used to disable a PI.
3.3 An example of a PIB
This section contains a simple example of a PIB describing a simple
set of filters for IP packets. Each filter is able to match either
the source IP address, the destination IP address or both. This
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example is provided only for the benefit of understanding how a PIB
is structured. It is not supposed to describe any actual policy data.
policyFilterPIB OBJECT IDENTIFIER ::= { policyPIB 1 }
ipHeaderFilterTable OBJECT-TYPE
SYNTAX SEQUENCE OF IpHeaderFilterEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION "This table contains a simple ACL, i.e. one or
more IP filters."
::= {policyFilterPIB 1}
ipHeaderFilterEntry OBJECT-TYPE
SYNTAX IpHeaderFilterEntry
MAX-ACCESS write-only
STATUS current
DESCRIPTION "Each row of the table has four columns. The
ipHeaderFilterIndex uniquely identifies a particular IP
filter. The ipHeaderFilterMatchType specifies the type of
match (source only, destination only, source and destination).
The ipHeaderFilterSourceAddress and
ipHeaderFilterDestinationAddress contain the source and
destination IP addresses."
INDEX {ipHeaderFilterIndex}
::= {ipHeaderFilterTable 1}
IpHeaderFilterEntry ::= SEQUENCE {
ipHeaderFilterIndex INTEGER,
ipHeaderFilterMatchType BITS,
ipHeaderFilterSourceAddress IpAddress,
ipHeaderFilterDestinationAddress IpAddress
}
ipHeaderFilterIndex OBJECT-TYPE
SYNTAX INTEGER
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION "The index of the table, used to identify each
individual IP filter"
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::= {ipHeaderFilterEntry 1}
ipHeaderFilterMatchType OBJECT-TYPE
SYNTAX BITS {
matchSource (0),
matchDestination (1)
}
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION "This field indicates which one or more of the
addresses are required to match the corresponding addresses
of the IP packet."
::= {ipHeaderFilterEntry 2}
ipHeaderFilterSourceAddress OBJECT-TYPE
SYNTAX IpAddress
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION "IP source address to be matched against the
packet in the event the ipHeaderFilterMatchType has the
corresponding bit set.
::= {ipHeaderFilterEntry 3}
ipHeaderFilterDestinationAddress OBJECT-TYPE
SYNTAX IpAddress
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION "IP destination address to be matched against the
packet in the event the ipHeaderFilterMatchType has the
corresponding bit set.
::= {ipHeaderFilterEntry 4}
4. COPS Diff Serv Client Data
The COPS-DS extensions define a new client type:
Client Type = 2; Diff Serv Client
Diff serv specific information is sent in a COPS message containing a
Common Header with the Diff Serv Client type specified:
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0 1 2
3
+----------------+----------------+----------------+----------------+
| Version| //// | Op Code | Client Type = 0x02 |
+----------------+----------------+----------------+----------------+
| Message Length |
+----------------+----------------+----------------+----------------+
The COPS protocol specification defines several objects which may
carry client specific information between PDP and PEP:
Context Object (Context)
Reason Object (Reason)
Decision Object (Decision)
Error Object (Error)
Client Specific Information Object (ClientSI) which includes:
Request ClientSI
Report ClientSI
Client-Open ClientSI
4.1 Policy Identifier (PID)
This object is used to carry the PID of the Policy Data Instance to
be installed or deleted.
0 1 2 3
+----------------+----------------+----------------+----------------+
| Length | Type = PID |
+----------------+----------------+----------------+----------------+
| Policy Identifier |
+----------------+----------------+----------------+----------------+
4.2 XDR Encoded Policy Instance Data (XPD)
This object is used to carry the value of a Policy Data Instance to
be installed, It contains an XDR coding of the Policy Data Instance
[RFC1832].
0 1 2 3
+----------------+----------------+----------------+----------------+
| Length | Type = "XDR type" |
+----------------+----------------+----------------+----------------+
| XDR Encoded PI Value |
+----------------+----------------+----------------+----------------+
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4.3 Diff Serv Decision Data
The diff serv Client Specific Decision Data is composed of one or
more bindings. Each binding associates a PID object and an XPD
object. The XPD object contains the value to be assigned to the PI
that is created or updated.
The diff serv specific decision data has the following format:
C-Num = 7
C-Type = 4
<Client Specific Decision Data> ::= <Install> |
<Delete> |
<Enable> |
<Disable>
<Install> :: = <Binding(s)>
<Binding(s)> ::= <Binding> <Binding(s)> |
<Binding>
<Binding> ::= <PID> <XPD>
<Delete> ::= <PI(s)>
<Enable> ::= <PI(s)>
<Disable> ::= <PI(s)>
<PI(s)> ::= <PI> <PI(s)> |
<PI>
4.4 Diff Serv Request Data
The diff serv request ClientSI data has the following format:
<diff serv request datat> ::= <Binding(s)>
4.5 Diff Serv Report Data
Diff serv specific report data is used in the RPT message. The format
of the report data is dependant on the value of the accompanying COPS
Report Type object.
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4.5.1 Commit Data
When used with the "commit" report type, the diff serv specific
report data has the following format:
<diff serv report data> ::= [<PID(s)>]
4.5.2 No Commit Data
When used with the "no commit" report type, the diff serv specific
report data has the following format:
<diff serv report data> ::= <Binding(s)>
4.5.3 Accounting Data
TBD
5. Message Content
This section describes the COPS messages exchanged between a PEP and
PDP for use with diff serv policy services.
5.1 Request (REQ) PEP -> PDP
The REQ message is used by COPS diff serv clients for issuing a
config request from the to the PDP, as described in the COPS
protocol. The Client Handle is associated with request state
originated by the PEP and the PEP is responsible for notifying the
PDP when the Handle is no longer in use and can be deleted.
The diff serv request data, defined above, may be included in the
config request form PEP to PDP. Currently, the request data is
defined for carrying configuration/feature negotiation information
from the PEP. This provides the server with information on the types
of policy that the interface can enforce and the types of policy data
the PEP can install.
The config request message serves as a request from the PEP to the
PDP for any diff serv configuration data which the PDP may have pre-
defined for the PEP device, such as access control lists, etc., and
any future access data or updates. The pre-configured and any
asynchronous diff serv configuration data can then be sent to the PEP
over time via responses, as decided by the PDP. The configuration
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information supplied by the PDP is of the consistent client specific
format defined above. The PDP responds to the config request with a
DEC message containing any available configuration information.
<Request> ::= <Common Header>
<Client Handle>
<Context = config request>
<interface>
<diff serv request data>
5.2 Decision (DEC) PDP -> PEP
The DEC message is sent from the PDP to a diff serv client in
response to a config REQ received from the PEP. The Client Handle
must be the same Handle that was received in the REQ message. The
Client Specific Decision Data for diff serv clients, to be used in
the DEC message, is defined above.
The DEC message is sent as an immediate response to a config request,
used to carry pre-defined configuration information set in the PDP,
to the PEP. Subsequent DECs may also be sent at any time after the
original DEC message to continue supplying the PEP with
additional/updated policy information. The state carried in the DEC
message is referred to in the PDP and PEP by the Client Handle and
the PID information.
The PEP performs the operation specified in the Decision Flags object
on the decision data. If no configuration state is available when the
config REQ is processed by the PDP, a DEC is sent with the "No
Configuration Data" decision flag set.
The "Install", "Delete", "Enable", and "Disable" decision flags are
used by the PEP and PDP to manage the policy data transactions. In
response to a DEC message, the diff serv client sends a RPT back to
the PDP to inform the PDP of the actual action taken. For example, in
response to a DEC with the "Install" flag (only) set, the PEP informs
the PDP if the decision data can be installed, based on the other
policy data on the device (are there conflicts, etc.). Then when the
PDP determines the policy should be enabled, based on the transaction
associated with the policy data, a subsequent DEC message may be sent
with the "Enable" flag set.
<Decision> ::= <Common Header>
<Client Handle>
<Decision Flags>
[< diff serv Specific Decision Data>]
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5.3 Report State (RPT) PEP -> PDP
The RPT message is sent from the diff serv client to the PDP to
report accounting information from PEP to PDP on request state
installed at the PEP. It is also used as a mechanism to inform the
PDP about the action taken at the PEP, in response to a DEC message.
The diff serv report data format, as defined above, depends on the
Report Type included in the RPT message.
<Report State> ::= <Common Header>
<Client Handle>
<Report Type>
[<diff serv report data>]
6. Common Operation
This section describes, in general, typical exchanges between a PDP
and diff serv COPS client.
First, a connection is established between the PEP and PDP and the
PEP sends a Client-Open message with the Client-Type = 2, Diff Serv
client. If the PDP supports the Diff Serv client, the PDP responds
with a Client-Accept (CAT) message. If the client type is not
supported, a Client-Close (CC) message is returned by the PDP to the
PEP, possibly identifying an alternate server that is known
(believed?) to support the policy for the diff serv client.
Once the CAT message is accepted, the client can send requests to the
server. The first request a COPS Diff Serv client sends to the server
is for configuration information, that is a REQ with "Configuration
Request" set in the context object that identifies a specific
interface/module and any relevant client specific information. The
config request message serves two purposes in COPS-DS. First, it is a
request from the PEP to the PDP for any diff serv configuration data
which the PDP may have pre-defined for the PEP device, such as acces
control lists, etc. Also, the config request is a request to the PDP
to send asynchronous diff serv configuration data to the PEP, as it
is received by the PDP. This asynchronous data may be new policy data
or an update to policy data sent previously.
If the PDP has diff serv QoS policy configuration information for the
client, that information is returned to the client in a DEC message
containing the Diff Serv client policy data within the COPS Decision
object. If no filters are defined, the DEC message will simply
specify that there are no filters using the "No Configuration"
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Decision Flags object. The handle associated with the request state
is the Client Handle sent in the original configuration REQ from the
PEP. This is to prevent the PEP from timing out the REQ and deleting
the Client Handle.
The PDP can then add new policy data or update existing state by
sending subsequent DEC message(s) to the PEP, with the same Client
Handle. The PEP is responsible for removing the Client handle when it
is no longer needed, for example when the interface goes down, and
informing the PDP that the handle is to be deleted.
For diff serv purposes, access state, and access requests to the
policy server can be initiated by other sources besides the PEP.
Examples of other sources include attached users requesting network
services via a web interface into a central management application,
or H.323 servers requesting resources on behalf of a user for a video
conferencing application. When such a request is accepted, the edge
device affected by the decision (the point where the flow is to enter
the network) must be informed of the decision. Since the PEP in the
edge device did not initiate the request, the specifics of the
request, e.g. flowspec, packet filter, and PHB to apply, must be
communicated to the PEP by the PDP. This information is sent to the
PEP using the Decision message containing Diff Serv client specific
data objects in the COPS Decision object as specified. Any updates to
the state information, for example in the case of a policy change or
call tear down, is communicated to the PEP by subsequent DEC messages
containing the same Client Handle and the updated diff serv request
state. Updates can be specify to delete, install, enable or disable
existing policy data.
The PEP acknowledges the DEC message and action taken by sending a
RPT message with a "Commit" Report-Type object. This serves as an
indication to the PDP that the requestor (e.g. H.323 server) can be
notified that the request has been accepted by the network. If the
PEP needs to reject the DEC operation for any reason, a RPT message
is sent with a Report-Type of value "No Commit" and optionally a
Client Specific Information object specifying the policy data that
was rejected. The PDP can then respond to the requestor accordingly.
The PEP can report to the PDP the local status of any installed
request state when appropriate. This information is sent in a Report-
State (RPT) message with the "Accounting" flag set. The state being
reported on is referenced by the Client Handle associated with the
request state and the client specific data identifier.
Finally, Client-Close (CC) messages are used to cancel the
corresponding Client-Open message. The CC message informs the other
side that the client type specified is no longer supported.
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7. Fault Tolerance
When communication is lost between PEP and PDP, the PEP attempts to
re-establish the TCP connection with the PDP it was last connected
to. If that server cannot be reached, then the PEP attempts to
connect to a secondary PDP, assumed at this time to be manually
configured at the PEP.
When a connection is finally re-established, either with the primary
PDP or a secondary PDP, the PDP may request the PEP to re-synch its
current state information (SSQ message). If after re-connecting, the
PDP does not request the synchronization, the client can assume the
server recognizes it and the current state at the PEP is correct. Any
changes state changes which occurred at the PEP while connection was
lost must be reported to the PDP in a RPT message.
While the PEP is disconnected from the PDP, the request state at the
PEP is to be used for policy decisions. If the PEP cannot re-connect
in some pre-specified period of time (some multiple of the keep-alive
time? - TBD), the request state is to be deleted and the associated
Handles removed. The same holds true for the PDP; upon detecting a
failed TCP connection, the time-out timer is started for the request
state associated with the PEP and the state is removed after the
specified period without a connection.
8. Security
The use of COPS for diff serv introduce no new security issues over
the base COPS protocol. The use of IPSEC between PDP and PEP, as
described in [COPS] is sufficient.
9. References
[COPS] Boyle, J., Cohen, R., Durham, D., Herzog, S., Raja,n R.,
Sastry, A., "The COPS (Common Open Policy Service)
Protocol", IETF <draft-ietf-rap-cops-02.txt>, March 1998.
[RAP] Yavatkar, R., et al., "A Framework for Policy Based
Admission Control",IETF <draft-ietf-rap-framework-00.txt>,
November, 1997.
[E2E] Bernet, Y., Yavatka,r R., Ford, P., Bake,r F., Nichols, K.,
Speer, M., "A Framework for End-to-End QoS Combining
Reichmeyer, Ho Chan, Durham, Gai, McCloghrie [Page
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COPS Usage for Differentiated Services August 1998
RSVP/Intserv and Differentiated Services", IETF <draft-
ietf-diffserv-rsvp-00.txt>, March 1998.
[RSVP] Braden, R., Zhang, L., Berson, S., Herzog, S., and Jamin,
S., "Resource Reservation Protocol (RSVP) Version 1
Functional Specification", IETF RFC 2205, Proposed
Standard, September 1997.
[ASN1] Information processing systems - Open Systems
Interconnection, "Specification of Abstract Syntax Notation
One (ASN.1)", International Organization for
Standardization, International Standard 8824, December
1987.
[RFC1832] R. Srinivasan, "XDR: External Data Representation
Standard.", RFC 1832, August 1995.
10. Author Information
Francis Reichmeyer
Bay Networks, Inc.
3 Federal Street
Billerica, MA 01821
Phone: (978) 916-3352
Email: freichmeyer@BayNetworks.COM
Kwok Ho Chan
Bay Networks, Inc.
600 Technology Park
Billerica, MA 01821
Phone: (978) 916-8175
Email: khchan@BayNetworks.COM
David Durham
Intel
2111 NE 25th Avenue
Hillsboro, OR 97124
Phone: (503) 264-6232
Email: david.durham@intel.com
Raj Yavatkar
Intel
2111 NE 25th Avenue
Hillsboro OR 97124
Phone: (503) 264-9077
Email: yavatkar@ibeam.intel.com
Reichmeyer, Ho Chan, Durham, Gai, McCloghrie [Page
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COPS Usage for Differentiated Services August 1998
Silvano Gai
Cisco Systems, Inc.
170 Tasman Dr.
San Jose, CA 95134-1706
Phone: (408) 527-2690
email: sgai@cisco.com
Keith McCloghrie
Cisco Systems, Inc.
170 Tasman Dr.
San Jose, CA 95134-1706
Phone: (408) 526-5260
email: kzm@cisco.com
Shai Herzog
IPHighway
2055 Gateway Place, Suite 400
San Jose, CA 95110
Phone: (408) 451-3923
Email: herzog@iphighway.com
...........
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