Moby Dick Consolidated System Integration Plan

D0103v1.doc Version 1 6.7.2003
Parameters:
MesgType
MesgLen
MN-info - stream of bytes of variable length
The structure of MN-info is as follows:
MN-info
in6_addr CoA-MN
in6_addr AR-Addr
Current Interface Name
4.1.2.8 Enhanced IPv6 stack
No further details are needed for this component.
4.1.2.9 DSCP Marking Software
Application 1 Application 2
Application level module
DSCP
matching
table
Fast Handover
module
Enhanced IPv6 stack
Standard IPv6 stack
MIPL
DSCP marking software
Network device drivers
TDCDMA WLAN Ethernet
Figure 24: Location of the DSCP marking software in the IP stack
The previous figure shows where the DMS (DiffServ Marking Software) will be located in the protocol
stack. It ”intercepts” packets just before transmitting them to the lower layer. Thus, all the packets
generated by both the IP stack and the upper layers can be filtered and marked.
4.1.2.9.1 Operation
When a new packet is ready to be transmitted to the layer two, the DMS inspects its header and consults a
DSCP Matching Table. This table contains a set of filters to apply on the information extracted from the
header, and the values of the associated DSCPs. Then, if one of the filters matches perfectly with this
information, the packet is marked with the value of the DSCP associated with this filter.
4.1.2.9.2 DMS Architecture
The DMS contains five components, as in figure 23:
• a DSCP Matching Table (DMT): this table contains the definition of every filter and the DSCP
associated with it in the Linux kernel space,
• a DSCP Marking Function (DMF): this is the DMS engine, which consults the fields in the different
headers of each packet, compares it with the filters in the DMT, and decides to mark or not the
packet with a new DSCP; it is located in the Linux kernel (in the IPv6 code),
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