In an EETimes.com article about a new dual-core PON chip from Broadlight, is this piece of information:

Director of marketing Dan Parsons said the gigabit PON market is splitting into two distinct segments. When the carrier puts network termination on the side of the house, the termination chip should be a simple transceiver device. But when it is embedded in a residential gateway, end users want a single system-on-chip to perform security, Wi-Fi access point, router and firewall duties.