Absamr-Active and programmable network allow innovative new se, -vices t m bo deployed rapidly. However, in a carrier grade network, il is imperative to maintain a sealable fast path mechanism 30 Ihat the delay and throughput requimmcntl arc mrt. This is p m t i d s r l y important since in many c a m ~itwork-IweI pmrrrsing is only needed for P subset of packets and the remainder of trilItic must he forwarded on the fast path. It is I challenge to design I e011 effective nodr archilectum that can ralirty this reqniremcnl. Currenl models are often 'malutionary' and may no1 scnlc to the required performance IeveIs of P carrier grade network In this paper we develop an evolutionary architecture that uses MPLS label stack lo enable efficient and ncalablr extraction Of active packets from the fast path without penaliring tho rest of the traffic. Our model can he u r d to extend the reach of programmable network Over legacy infrastructure and provide a migratoly path for existing carriers towards a programmable 1nfnsfr"eture.