[e2e] Routers accessing TCP header

[Arjuna Sathiaseelan]

Dear all,
  I have implemented a mechanism which requires routers to access the TCP
header from the IP packet mainly the TCP sequence numbers. Implementing
this on ns-2 is not a problem. But in real world, is this a possibility?
Can the routers access the TCP header mainly the TCP sequence numbers? I
would be very much obliged if someone could help me with this.

Regards,
Arjuna