Debugging UDP

Hello All,

I am trying to understand the architecture ( high level ) of UDP protocol plus supporting protocols ( server 2008 r2 )

when I uncheck IPV6 from adapter , my queries on UDP 389 fails.

Network components are at both Kernel mode and User mode. Starting from NDIS , there is TCPIP.sys which has the kernel level implementation of UDP , TCP/IP and IPSEC, followed by the TDI and winsock kernel mode implementation.

At the user mode ( transport layer ) there are Transport service providers, winsock , apps

I am trying to stitch the communication flow between various components and its getting harder for me to understand the flow

when I uncheck the TCP IP V6 from nic adapter
Netshell.dll get called which binds or unbinds the protocol –> ( ambiguity ) about how the flow enters

if a protocol stops responding to the port ,this behavior governed at the kernel level ( tcpip.sys ) - I may be wrong though

any help to understand communication flow is greatly appreciated