draft-ietf-dhc-pv4-reconfigure-02.txt   draft-ietf-dhc-pv4-reconfigure-03.txt 
Submitted to DHC Working Group Peter De Schrijver Submitted to DHC Working Group Peter De Schrijver
INTERNET DRAFT Yves T'Joens INTERNET DRAFT Yves T'Joens
<draft-ietf-dhc-pv4-reconfigure-02.txt> Christian Hublet <draft-ietf-dhc-pv4-reconfigure-03.txt> Christian Hublet
Alcatel Alcatel
November 2000 April 2001
Expires June, 2001 Expires September, 2001
DHCP reconfigure extension DHCP reconfigure extension
Status of this memo Status of this memo
This document is an Internet-Draft and is in full conformance with This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026. all provisions of Section 10 of RFC2026.
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Abstract Abstract
This draft defines extensions to DHCP [DHCP] to allow dynamic This draft defines extensions to DHCP [DHCP] to allow dynamic
reconfiguration of a single host triggered by the DHCP server (eg. a reconfiguration of a single host triggered by the DHCP server (eg. a
new IP address). This is achieved by introducing a unicast DHCP new IP address). This is achieved by introducing a unicast DHCP
FORCERENEW message which forces the client to the RENEW state. FORCERENEW message which forces the client to the RENEW state. The
behaviour for hosts using the DHCP INFORM message to obtain
configuration information is also described.
1. Introduction 1. Introduction
The procedures as described within this draft allow the dynamic The procedures as described within this draft allow the dynamic
reconfiguration of individual hosts. reconfiguration of individual hosts.
1.1 Conventions 1.1 Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY" and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY" and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
2. DHCP force renew 2. DHCP force renew
This section describes the DHCP force renew extension. This section describes the DHCP force renew extension.
2.1 Terminology 2.1 Terminology
skipping to change at page 2, line 35 skipping to change at page 2, line 38
init state and broadcast a DHCP DISCOVER message. The server can now init state and broadcast a DHCP DISCOVER message. The server can now
assign a new IP address to the client by replying with a DHCP OFFER. assign a new IP address to the client by replying with a DHCP OFFER.
If the force renew message is lost, the DHCP server will not receive If the force renew message is lost, the DHCP server will not receive
a DHCP REQUEST from the client and it should retransmit the DHCP a DHCP REQUEST from the client and it should retransmit the DHCP
FORCERENEW message using an exponential backoff algorithm. Depending FORCERENEW message using an exponential backoff algorithm. Depending
on the bandwidth of the network between server and client, the server on the bandwidth of the network between server and client, the server
should choose a delay. This delay grows exponentially as should choose a delay. This delay grows exponentially as
retransmissions fail. The amount of retransmissions should be retransmissions fail. The amount of retransmissions should be
limited. limited.
It can be that a client has obtained a network address through some
other means (e.g., manual configuration) and has used a DHCPINFORM
request to obtain other local configuration parameters. Such clients
should respond to the receipt of DHCP FORCERENEW message with a new
DHCP INFORM request so as to obtain a potential new set of local
configuration parameters.
2.3 Rationale 2.3 Rationale
This approach has a number of advantages. It does not require new This approach has a number of advantages. It does not require new
states to be added to the DHCP client implementation. This minimizes states to be added to the DHCP client implementation. This minimizes
the amount of code to be changed. It also allows lease RENEWAL to be the amount of code to be changed. It also allows lease RENEWAL to be
driven by the server, which can be used to optimize network usage or driven by the server, which can be used to optimize network usage or
DHCP server load. DHCP server load.
3. Extended DHCP state diagram 3. Extended DHCP state diagram
skipping to change at page 4, line 24 skipping to change at page 4, line 24
As in some network environments DHCPFORCERENEW can be used to snoop As in some network environments DHCPFORCERENEW can be used to snoop
and spoof traffic, the DHCPFORCERENEW message MUST be authenticated and spoof traffic, the DHCPFORCERENEW message MUST be authenticated
using the procedures as described in [DHCP-AUTH]. using the procedures as described in [DHCP-AUTH].
7. References 7. References
[DHCP] R.Droms, "Dynamic Host Configuration Protocol", RFC 2131, [DHCP] R.Droms, "Dynamic Host Configuration Protocol", RFC 2131,
March 1997. March 1997.
[DHCP-AUTH] R. Droms et al., "Authentication for DHCP Messages", [DHCP-AUTH] R. Droms et al., "Authentication for DHCP Messages",
draft-ietf-dhc-authentication-14, July 2000, Work in progress. RFCxxxx, yyyy 2001.
[RFC2119] S. Bradner, "Key words for use in RFCs to Indicate [RFC2119] S. Bradner, "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
8. Acknowledgements
The authors would like to thank David Allen, Nortel, for the
contribution to these procedures.
9. Contacts 9. Contacts
Peter De Schrijver Peter De Schrijver
Alcatel Network Strategy Group Alcatel Network Strategy Group
Francis Wellesplein 1, 2018 Antwerp, Belgium Francis Wellesplein 1, 2018 Antwerp, Belgium
Phone : +32 3 240 8569 Phone : +32 3 240 8569
E-mail : peter.de_schrijver@alcatel.be E-mail : peter.de_schrijver@alcatel.be
Yves T'joens Yves T'joens
Alcatel Network Strategy Group Alcatel Network Strategy Group
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