IP mobility support for IPv4 nodes (hosts and routers) is specified in RFC3344. RFC 3344 mobility allows a node to continue using its "permanent" home address as it moves around the Internet. The Mobile IP protocols support transparency above the IP layer, including maintenance of active TCP connections and UDP port bindings.Besides the basic Mobile IPv4 (MIPv4) protocols, several other drafts deal with concerns such as optimization, security, extensions, AAA support, and deployment issues. MIPv4 is currently being deployed on a wide basis (e.g., in cdma2000 networks). The scope of the deployment is on a fairly large scale and accordingly, the MIP4 WG will focus on deployment issues and on addressing known deficiencies and shortcomings in the protocol that have come up as a result of deployment experience. Specifically, the working group will complete the work items to facilitate interactions with AAA environments, interactions with enterprise environments when MIPv4 is used therein, and updating existing protocol specifications in accordance with deployment needs and advancing those protocols that are on the standards track. Work expected to be done by the MIP4 WG as proposed by this charter is as follows: 1. MIPv4 has been a proposed standard for several years. It has been adopted by other standard development organizations and has been deployed commercially. One of the next steps for the WG is to advance the protocol to draft standard status. As part of advancing base Mobile IP specs to DS, the MIPv4 NAI RFC (2794) will be revised to reflect implementation experience 2. Work items that are pending from the previous Mobile IP WG, which will be completed by the MIP4 WG, are: - completion of the MIB for the revised base Mobile IP specification (2006bis) - regional registration draft. 3. The MIP4 WG will also complete the work on MIPv4 interactions in VPN scenarios. This work will involve identifying the requirements and a solution development for MIPv4 operation in the presence of IPsec VPNs. 4. Additionally, a proposal has been made for how MOBIKE could work together with MIPv4. This proposal does not describe any new protocol, but formulates a best current practice for deploying MOBIKE together with MIPv4. The working group will adopt and complete this document. 5. Some issues have been raised with respect to RFC3519. These will be identified and addressed as appropriate, through errata, revision of RFC 3519, and/or supplemental documents as needed. 6. It has been proposed that the FMIP protocol, which has been standardised for MIPv6 in the MIPSHOP working group, should also be published as an experimental protocol for MIPv4. A draft for this exists. The working group will take up and carry this work forward to publication 7. An extension to carry generic strings in the Registration Reply message has been proposed. The purpose is to supply supplemental human-readable information intended to the MN user. The working group will complete the specification and applicability statement of such an extension. 8. RADIUS attributes for MIP4. A set of RADIUS attributes has been proposed for MIPv4. The working group will first produce a requirements specification, describing how the work differs from the requirements in RFC 2977 and the functionality provided by RFC 4004 (the MIPv4 Diameter App). The reason why this first step is required is that RFC 3127 pretty clearly shows that full 2977 functionality can't be provided by even a considerably extended RADIUS, so we need to match the requirements to what can be done within RADIUS. Provided the requirements work finds approval with ADs and radext, the workgroup will complete the specification of MIPv4 RADIUS attributes, solicit feedback from the Radius Extensions WG, adjust, and submit this for publication. 9. MIPv4 Extension for Configuration Options. Several drafts have proposed extensions to help improve configuration of MIPv4 clients. The latest proposal is for a general configuration option extension which could carry information such as e.g., DNS address and DHCP server address. The working group will take on and complete one proposal for a configuration option extension.