Moby Dick Consolidated System Integration Plan

D0103v1.doc Version 1 6.7.2003
The IPSec and Mobile-Ipv6 functionality within the kernel is provided by a software package called
SWAMP. It is accompanied by a userspace library called liburp, which aids in writing a User-
Registration-Protocol handler program.
The major component of SWAMP consists of patches to the Linux kernel version 2.4.16 which provides
IPSec and Mobile-Ipv6 functionality. SWAMP is not an implementation from-scratch. It merely takes
two existing projects for providing support for these technologies in the Linux kernel and integrates them.
It is not possible to apply them independently to the same kernel.
The liburp provides a simplified interface to the IPSec functionalities of the kernel, since the native API
exposed by IPSec (called PFKey) is quite complex and its fully generic behaviour is not needed in
MobyDick.
In addition, the liburp package provides a kernel module, called pep6_kmod, and an API to control this
module from userspace. This module implements simple but powerful packet filtering functions. Using
this, a user-space program (such as the AAA Attendant in MobyDick) can implement access control
based on user authentication.
Since the Mobile -Ipv6 functionality is the same as that provided by the MIPL implementation by HUT, it
is not described here.
4.2.2.3 Fast Handover Module / MIPL
The fast handover module (FHM) is responsible for fast handover procedures in the access router.
QoS manager
AAA
Attendan
t
Fast Handover
module
QoS
attendant
PEP
DSCP
TABLE
Enhanced IPv6 stack
Standard IPv6 stack
Internal interface
IPSec
Diffserv
Packet filter
Kernel space
User space
Figure 32: Fast Handover module and its relationship with other modules
Figure 32 shows the fast handover module and the interfaces between this module and others in the AR
architecture.
Communication between the FHM and the AAAC attendant is for the following purposes:
• The FHM will inform the AAAC attendant when a MT is expected to execute a handover to this
AR, i.e. a Handover Initiate message has been received and the nCoA proposed has been
checked and is correct.
• The FHM will inform the AAAC attendant when a handover procedure has ended with the
result of a MT finishing using the AR services, this will allow the AAAC attendant to finish the
accounting for this MT and sending the pending accounting information to the AAAC server.
Communication between the FHM and the QoS attendant is for the following purpose:
• The FHM will send a message to the QoS attendant in the oAR when a MT is expected to
execute a handover to the nAR. QoS attendant will indicate the PEP to perform a QoS context
transfer using the QoS infrastructure.
• Also the QoS attendant tells the FHO module of the availability or not of QoS resources in the
nAR during the FHO process.
The fast handover module on the access router is mainly responsible for the inter-access router
communication and the bi-casting of data, which is destined for the mobile node, during the handover
process. Conceptually, MIPL is not required on the access router, but currently, the fast handover
modules accesses functionalities of the mobility module and therefore the MIPL module is mentioned
here in combination with the fast handover module. Again the sending and receiving functions of the
(enhanced) IPv6 stack are to be made accessible without explicit interface specification. Interactions to
other modules than the IPv6 stack are not required on the access router.
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