As the extension part of IP backbone data network to local city

IP MAN used to bear the low ranking public service

while with the incoming of all service operation era

more attention should be attached to the IP MAN service protection to meet subscribers’ increasing requirements for QoS of internet service.This article give a analysis and discussion on the networking strategy for IP MAN service protection

with consideration to the current IP MAN architecture and data link detection mechanism

in order to improve the security of the service over IP MAN and guarantee the smooth rollout of service operation.