Znyx Networks bh5700 Manuale Utente
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The PDP sends that policy to the PEP.
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The PEP installs the policy and applies it to future traffic.
As long as COPS is running, a connection between the PEP and PDP should stay open. A PEP
could query a PDP at any time asking for a policy decision. Alternatively, an administrator could
modify the policy on a PDP, which would then push any policy changes to its PEPs.
could query a PDP at any time asking for a policy decision. Alternatively, an administrator could
modify the policy on a PDP, which would then push any policy changes to its PEPs.
Protocol Architecture
The COPS protocol is broken into several components. The base layer is the COPS protocol
itself, which defines the messaging format. This protocol defines how communication is handled
without specifying the details of the message data.
itself, which defines the messaging format. This protocol defines how communication is handled
without specifying the details of the message data.
The base COPS protocol is then used by different client types. These client types apply the COPS
messaging scheme to particular types of data. The currently standardized client types deal with
the RSVP model (COPS-RSVP) and provisioning model (COPS-PR).
messaging scheme to particular types of data. The currently standardized client types deal with
the RSVP model (COPS-RSVP) and provisioning model (COPS-PR).
The COPS-RSVP scheme is designed around the requirement that a PEP will have to query a
PDP in response to events. An RSVP PEP is constantly listening for resource reservation requests
and relaying those requests to its PDP.
PDP in response to events. An RSVP PEP is constantly listening for resource reservation requests
and relaying those requests to its PDP.
By contrast, the provisioning model is based on longer lasting policy. The expectation is that
policy should be administratively defined at the PDP and pushed to the PEPs as needed.
OpenArchitect is a COPS-PR client.
policy should be administratively defined at the PDP and pushed to the PEPs as needed.
OpenArchitect is a COPS-PR client.
The most common use of COPS-PR is for distributing Differentiated Services (Diffserv) policy.
Diffserv is concerned with such Quality of Service elements as queues and schedulers.
Diffserv is concerned with such Quality of Service elements as queues and schedulers.
OpenArchitect PEP
The OpenArchitect PEP implementation is known as pepd. The pepd utility is based on:
RFC 2478: Common Open Policy Service (COPS)
RFC 3084: COPS Usage for Policy Provisioning
RFC 2478: Common Open Policy Service (COPS)
RFC 3084: COPS Usage for Policy Provisioning
RFC 3159: Structure of Policy Provisioning Information
RFC 3289: Management Information Base (MIB) for the Differentiated Services Architecture
Internet Draft: Differentiated Services Quality of Service Policy Information Base (latest version
draft-ietf-diffserv-pib-09)
draft-ietf-diffserv-pib-09)
Internet Draft: Framework Policy Information Base (latest version draft-ietf-rap-frameworkpib-
09)
09)
A Policy Information Base (PIB) defines the representation of a particular data set. For example,
the Diffserv PIB specifies the structures used to represent all Diffserv elements. PIBs are
functionally equivalent to Management Information Bases (MIBs) such as those used by SNMP.
The OA PEP has implemented those portions of the Diffserv and Framework PIBs that are
supported by the underlying switch architecture.
the Diffserv PIB specifies the structures used to represent all Diffserv elements. PIBs are
functionally equivalent to Management Information Bases (MIBs) such as those used by SNMP.
The OA PEP has implemented those portions of the Diffserv and Framework PIBs that are
supported by the underlying switch architecture.
Ethernet Switch Blade User's Guide
release 3.2.2j
page 71