Challenges of IPv6 Flow Label implementation

The Internet Protocol version 6 (IPv6) protocol represents an emerging networking capability designed to enhance transport, management and security of IP packets through the networks. IPv6 packet header required for this protocol is much larger than that of the current IPv4 protocol. The processing of IPv6 packets can be complex depending on how many packet header options are needed for a given mode of transmission. There are currently no standards available from Internet Engineering Task Force (IETF), the body that develops all Internet networking standards, related to the use of the flow label. The current IETF standards define the concept of flow of IP packets based on the three tuple of source and destination addresses and the flow label. This definition requires that the bit content of flow label be delivered unmodified at the destination end-system. However, this requirement has its disadvantages in that the network treats the flow label as a component of the fixed bit space of the packet header - not unlike the address bits. This paper discusses an emerging flow label technology called 6LSA and then examines the challenges associated with Flow Label implementation as originally conceived and the advantages of the current state of using the Flow Label.