Network Working Group G. Zorn Internet-Draft Microsoft Corporation Category: Informational February 1998 <draft-ietf-radius-bap-00.txt> RADIUS Attributes for Multilink PPP Banwidth Allocation Control 1. Status of this Memo This document is an Internet-Draft. Internet-Drafts are working docu- ments of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working doc- uments as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as ``work in progress''. To learn the current status of any Internet-Draft, please check the ``1id-abstracts.txt'' listing contained in the Internet-Drafts Shadow Directories on ds.internic.net (US East Coast), nic.nordu.net (Europe), ftp.isi.edu (US West Coast), or munnari.oz.au (Pacific Rim). This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind. The distribution of this memo is unlimited. It is filed as <draft-ietf-radius-ms-ba- attr-00.txt> and expires August 15, 1998. Please send comments to the RADIUS Working Group mailing list (ietf-radius@livingston.com) or to the author (glennz@microsoft.com). 2. Abstract This document describes a set of vendor-specific RADIUS attributes designed to support the dynamic control of bandwidth allocation in mul- tilink PPP [1]. Attributes are defined that specify whether use of the PPP Bandwidth Allocation Protocol [2] is allowed or required on incoming calls, the level of line capacity (expressed as a percentage) below which utilization must fall before a link is eligible to be dropped, and the length of time (in seconds) that a link must be underutilized before it is dropped. Zorn [Page 1]
INTERNET-DRAFT BAP RADIUS Attributes February 1998 3. Specification of Requirements In this document, the key words "MAY", "MUST, "MUST NOT", "optional", "recommended", "SHOULD", and "SHOULD NOT" are to be interpreted as described in [3]. 4. Attributes The following sections describe sub-attributes which may be transmitted in one or more RADIUS attributes of type Vendor-Specific [4]. More than one sub-attribute MAY be transmitted in a single Vendor-Specific Attribute; if this is done, the sub-attributes SHOULD be packed as a sequence of Vendor-Type/Vendor-Length/Value triples following the inital Type, Length and Vendor-ID fields. The Length field of the Vendor-Spe- cific Attribute MUST be set equal to the sum of the Vendor-Length fields of the sub-attributes contained in the Vendor-Specific Attribute, plus six. The Vendor-ID field of the Vendor-Specific Attribute(s) MUST be set to decimal 311 (Microsoft). 4.1. BAP-Usage Description This Attribute describes whether th use of BAP is allowed, disal- lowed or required on new multilink calls. It MAY be used in Access-Accept packets. A summary of the BAP-Usage Attribute format is shown below. The fields are transmitted from left to right. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Vendor-Type | Vendor-Length | Value +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Value (cont) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Vendor-Type 13 for BAP-Usage. Vendor-Length 6 Value The Value field is four octets. Zorn [Page 2]
INTERNET-DRAFT BAP RADIUS Attributes February 1998 0 BAP usage not allowed 1 BAP usage allowed 2 BAP usage required 4.2. Link-Utilization-Threshold Description This Attribute represents the percentage of available bandwidth utilization below which the link must fall before the link is eli- gible for termination. Permissible values for the Link-Utiliza- tion-Threshold Attribute are in the range 1-100, inclusive. It is only used in Access-Accept packets. A summary of the Link-Utilization-Threshold Attribute format is shown below. The fields are transmitted from left to right. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Vendor-Type | Vendor-Length | Value +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Value (cont) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Vendor-Type 14 for Link-Utilization-Threshold Vendor-Length 6 Value The Value field is four octets in length and represents the per- centage of available bandwidth utilization below which the link must fall before the link is eligible for termination. Permissi- ble values are in the range 1-100, inclusive. 4.3. Link-Drop-Time-Limit Description The Link-Drop-Time-Limit Attribute indicates the length of time (in seconds) that a link must be underutilized before it is dropped. It MAY only be included in Access-Accept packets. A summary of the Link-Drop-Time-Limit Attribute format is given Zorn [Page 3]
INTERNET-DRAFT BAP RADIUS Attributes February 1998 below. The fields are transmitted left to right. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Vendor-Type | Vendor-Length | Value +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Value (cont) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Vendor-Type 15 for Link-Drop-Time-Limit Vendor-Length 6 Value The Value field represents the number of seconds that a link must be underutilized (i.e., display bandwidth utilization below the threshold specified in the Link-Utilization-Threshold Attribute) before the link is dropped. 5. Table of Attributes The following table provides a guide to which of the above attributes may be found in which kinds of packets, and in what quantity. Request Accept Reject Challenge Acct-Request # Attribute 0 0-1 0 0 0 13 BAP-Usage 0 0-1 0 0 0 14 Link-Utilization-Threshold 0 0-1 0 0 0 15 Link-Drop-Time-Limit The following table defines the meaning of the above table entries. 0 This attribute MUST NOT be present in packet. 0+ Zero or more instances of this attribute MAY be present in packet. 0-1 Zero or one instance of this attribute MAY be present in packet. 6. Security Considerations None. Zorn [Page 4]
INTERNET-DRAFT BAP RADIUS Attributes February 1998 7. Acknowledgements Thanks to Narendra Gidwani (nareng@microsoft.com) for useful comments. 8. Expiration Date This document expires August 15, 1998. 9. Chair's Address The RADIUS Working Group can be contacted via the current chair: Carl Rigney Livingston Enterprises 4464 Willow Road Pleasanton, California 94588 Phone: +1 510 426 0770 E-Mail: cdr@livingston.com 10. Author's Address Questions about this memo can also be directed to: Glen Zorn Microsoft Corporation One Microsoft Way Redmond, Washington 98052 Phone: +1 425 703 1559 FAX: +1 425 936 7329 EMail: glennz@microsoft.com 11. References [1] Sklower, K., et. al., "The PPP Multilink Protocol (MP)", RFC 1990, August 1996 [2] Richards, C. and Smith, K., "The PPP Bandwidth Allocation Protocol (BAP) The PPP Bandwidth Allocation Control Protocol (BACP)" RFC 2125, March 1997 [3] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", RFC 2119, March 1997 Zorn [Page 5]
INTERNET-DRAFT BAP RADIUS Attributes February 1998 [4] Rigney, C., et. al., "Remote Access Dial In User Service", RFC 2138, April 1997 Zorn [Page 6]
