In the latest turn of a long game of cat-and-mouse, BitTorrent developers has said they are working on extensions to the core peer-to-peer (P2P) protocol to better thwart efforts to detect and throttle down heavy BitTorrent users.

The BitTorrent community has made efforts to thwart traffic-shaping before. But the issue has hit new heights lately as telcos and cable companies – most notably Comcast, which has caught the most heat, including FCC attention – have turned to new tactics to manage P2P traffic.

Among the new approaches are deep packet inspection, or DPI, which service providers use to determine the contents of Internet traffic. More controversially, Comcast and vendor partner Sandvine have been accused of forging and sending packets that disconnect peer connections – essentially knocking down BitTorrent downloads before they begin.

Traffic-shaping issues have moved to the forefront, with a new pass at a Net neutrality bill making the rounds last week, albeit without heavy enforcement or penalty provisions. Meanwhile, the FCC last month opened rule-making proceedings over BitTorrent blocking, with Comcast and many of its BitTorrent rivals making filings last week hashing out their views on the issue. The FCC deadline for replies on the initial comments is February 28.

For its part, Comcast said it isn’t “blocking” P2P traffic but delaying it during heavy traffic periods. “This action is nothing more than the system saying that it cannot, at that moment, process additional high-resource demands without becoming overwhelmed, just as a traffic ramp control light regulates the entry of additional vehicles onto a freeway during rush hour,” Comcast said in its 80-page filing.

P2P company Vuze, the main petitioner in the proceedings, said in its filing, “Comcast’s actions starkly raise the issue of whether broadband network operators should be permitted the unfettered discretion to restrict or block traffic carried on their networks and to censor legal content or discriminate against applications and services that they may perceive as competing with their offerings.”

Service providers have generally been trying to distance themselves from the issue from a public relations perspective – with Tom Tauke, Verizon’s executive vice president for public affairs, even telling the NY Times earlier this month that Verizon is “reluctant to get into the business of examining content that flows across our networks and taking some action as a result of that content.” That said, AT&T, Verizon and Qwest last week all submitted filings that call for network providers to be able to manage their networks as they see fit.

As competitors wage legal battle at the FCC, BitTorrent community blog TorrentFreak Monday detailed new efforts to update the BitTorrent protocol to combat such efforts. The addition to the protocol is designed to prevent ISPs from inserting forged TCP reset packets and disrupting the span between the receiver of a tracker response and any peer IP-Port appearing in that tracker response. The detailed proposal can be found here.

“The objective is NOT to create a cryptographically secure protocol that can survive unlimited observation of passing packets and substantial computational resources on network timescales,” according to the proposal, written by four BitTorrent developers. “The objective is to raise the bar sufficiently to deter attacks based on observing IP-port numbers in peer-to-tracker communications.”

The protocol enhancement, dubbed “Tracker Peer Obfuscation,” is being advanced as part of the open source BitTorrent Community Forum process. Enhancements to the core BitTorrent protocol are called BitTorrent Enhancement Proposals, which means the enhancement is still in development and not ready to be deployed.

The BitTorrent community has considered using SSL or other public key encryption to more fully secure entire BitTorrent streams, but that would require a significant upgrade – not only software but raw hardware processing power as well – at BitTorrent trackers, the servers that act as the directory and traffic cop connecting BitTorrent peers.