Prepaid Extensions to RADIUS

1

• Prepaid Extensions to RADIUS
• (draft-lior-radius-prepaid-extensions-10.txt)
• A. Lior Bridgewater Systems
• P. Yegani Cisco Systems
• K. Chowdhury Starent Networks
• H. Tschofenig Siemens
• A. Pashalidis Siemens
• ltslides by Andreas Pashalidisgt

2

• Whats new in -10
• Aligned with Diameter Credit Control
• i.e. RADIUS Prepaid now supports
• Balance check are sufficient funds available for
• a given service in the user account?
• Price enquiry how is a given service rated? The
• response AVP returns the cost information for
  the
• requested service
• Detailed example message flows
• Simple flow
• Flow with tariff switching
• Flow with resource pools, rating groups, and
• multiple services

3

• Whats new in -10
• Contains high level description of translation
  agent between RADIUS prepaid and Diameter Credit
  Control for scenarios below
• RADIUS PP-based client, Diameter CC-based AAA
  infrastructure
• Diameter CC-based client, RADIUS PP-based
  infrastructure
• No more reliance on Authorize-Only

4

• RADIUS Design Guidelines
• (Ref draft-weber-radius-attr-guidelines-02.txt)
• Backwards Compatibility 6.1
• Intermediate nodes 6.1.1
• Dictionary-based implementations 6.1.2
• Unaware endpoints 6.1.3
• Existing Vendor-Specific Attribute Usage 6.2
• Transport Impact 6.3
• Diameter Compatibility 6.5
• Security 6.6
• Hence it appears that all guidelines are
• respected (pending peers review)

5

• RADIUS PP vs DIAMETER CC
• RADIUS Prepaid uses a grouped AVP
• (as does Diameter Credit Control)
• see section 4.3.19
• Translation Agent in Diameter CC-based
• client, RADIUS Prepaid-based infrastructure
• case not described (yet)
• Is tricky due to many Diameter Credit Control
• AVPs and few RADIUS Prepaid Attributes
• Some AVPs are semantically only partially
• equivalent

6

• Open issues
• Translation between RADIUS Prepaid and Diameter
  Credit Control
• Diameter TCP-based messages include quota
• difference from previous quota
• RADIUS UDP-based message include cumulative
• quota since start of session
• Hence either translation agent needs per
• session state, or excessively large state
• AVPs (e.g. in multiple services scenario)

7

• Next Step
• Should this be a WG item?