DHC R. George Internet-Draft Huawei Technologies Intended status: BCP June 25, 2012 Expires: December 27, 2012 DHCPv6 Request Retransmission draft-george-dhc-request-retransmission-00 Abstract The DHCP client sends SOLICIT message to get IP address from the server. If the address pool is empty, all address in the pool have allocated to the clients, the server will return error code. NoAddrsAvail (server has no address available to assign in the IA). Client retransmit the SOLICIT message (section 14 RFC 3315) and may get the same response. This draft defines a new suboption for the Dynamic Host Configuration Protocol (DHCP) to identify the retry time to sent next SOLICIT message. Hence, avoid unnecessary retransmit of SOLICIT messages. The suboption carries a value that identifies when an address will be available in the address pool. Status of this Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. 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." This Internet-Draft will expire on December 27, 2012. Copyright Notice Copyright (c) 2012 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents George Expires December 27, 2012 [Page 1] Internet-Draft DHCPv6 Request Retransmission June 2012 (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology used in this document . . . . . . . . . . . . . . . 3 3. Option Format . . . . . . . . . . . . . . . . . . . . . . . . . 3 4. Security Considerations . . . . . . . . . . . . . . . . . . . . 4 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 4 6. References . . . . . . . . . . . . . . . . . . . . . . . . . . 4 6.1. Normative References . . . . . . . . . . . . . . . . . . . 4 6.2. Informative References . . . . . . . . . . . . . . . . . . 4 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 4 George Expires December 27, 2012 [Page 2] Internet-Draft DHCPv6 Request Retransmission June 2012 1. Introduction To avoid the retry after getting a NoAddrAvail status message from the server, add a new DHCP option, retry-after. The server may return retry-after message with a value that is the time when an IP address is available in the server address pool.(it can be calculated as MIN(t3-current time) for all the client got address from the server. Client may avoid retry till retry-after value, if NoAddrsAvail received.. 2. Terminology 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]. 3. Option Format The format of the Retry after suboption. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | OPTION_RETRY_AFTER_TIME | Option-len | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | RETRY-TIME | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- option-code OPTION_RETRY_AFTER_TIME (TBD). option-len 2. elapsed-time The amount of time the client has to wait to get an address from this server. This time is expressed in hundredths of a second (10^-2 seconds). George Expires December 27, 2012 [Page 3] Internet-Draft DHCPv6 Request Retransmission June 2012 4. Security Considerations The security considerations of [RFC3315] and [RFC2131] are relevant to this document. 5. IANA Considerations TBD 6. References 6.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. 6.2. Informative References [RFC2131] Droms, R., "Dynamic Host Configuration Protocol", RFC 2131, March 1997. [RFC2434] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 2434, October 1998. [RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C., and M. Carney, "Dynamic Host Configuration Protocol for IPv6 (DHCPv6)", RFC 3315, July 2003. Author's Address Robins George Huawei Technologies Solitaire Bangalore, Karnataka 560071 India Phone: +918041117676 Email: robinsgv@gmail.com George Expires December 27, 2012 [Page 4]