Efficient remote phy dataplane management for a cable system

Abstract

A cable distribution system that includes a headend connected to a plurality of customer devices through a transmission network that includes a remote fiber node that converts digital data to analog data suitable for the plurality of customer devices. The remote fiber node receiving a downstream external protocol interface packet that includes a header portion and a data portion in memory. The remote fiber node encoding and transmitting the data portion to at least one of the plurality of customer devices, wherein the data portion is transferred from the memory using direct memory access based upon a buffer descriptor for the encoding.

We claim: 
     
         1 . A cable distribution system that includes a headend connected to a plurality of customer devices through a transmission network that includes a remote fiber node that converts digital data to analog data suitable for said plurality of customer devices, where said remote fiber node includes a processor, comprising:
 (a) said remote fiber node receiving a downstream external protocol interface packet that includes a header portion and a data portion in memory;   (b) said remote fiber node encoding and transmitting said data portion to at least one of said plurality of customer devices; and   (c) wherein said data portion is transferred from said memory using direct memory access based upon a buffer descriptor for said encoding.   
     
     
         2 . The cable distribution system of  claim 1  wherein said downstream external protocol interface packet includes (1) said header portion including a network header, a protocol header, a tunneling header, a protocol header, and (2) said data portion including a data payload. 
     
     
         3 . The cable distribution system of  claim 2  wherein said network header is Ethernet, said protocol header is an IP header, said tunneling header is at least one of a layer 2 tunnel protocol and a layer 3 tunnel protocol, said protocol header is a DEPI header, and said data payload includes DOCSIS data. 
     
     
         4 . The cable distribution system of  claim 3  wherein said downstream external protocol interface packet includes multiple channels. 
     
     
         5 . The cable distribution system of  claim 4  wherein said multiple channels includes at least one of a data traffic, a video traffic, a NDF traffic, a DOCSIS 1.0 traffic, a DOCSIS 2.0 traffic, a DOCSIS 3.0 traffic, a DOCSIS 3.1 traffic, an out of band traffic, a SCTE 55-1 traffic, and a SCTE 55-2 traffic. 
     
     
         6 . The cable distribution system of  claim 5  wherein said downstream external protocol interface packet is encapsulated as a DOCSIS MPEG Transport that includes DOCSIS frames over MPEG over L2TP. 
     
     
         7 . The cable distribution system of  claim 5  wherein said downstream external protocol interface packet is encapsulated as a packet streaming protocol streaming DOCSIS frames over L2TP. 
     
     
         8 . The cable distribution system of  claim 1  wherein said remote fiber node encoding and transmitting said data portion includes analog QAM modulation. 
     
     
         9 . The cable distribution system of  claim 1  wherein said data portion is transferred from said memory using direct memory access for said encoding free from being copied to another portion of said memory. 
     
     
         10 . The cable distribution system of  claim 1  wherein said direct memory access is performed based upon a direct memory access controller. 
     
     
         11 . The cable distribution system of  claim 1  wherein said buffer descriptor is a structure that includes an address in said memory. 
     
     
         12 . The cable distribution system of  claim 11  wherein said buffer descriptor further includes a size. 
     
     
         13 . The cable distribution system of  claim 12  wherein said buffer descriptor further includes a start of packet indicator and an end of packet indicator. 
     
     
         14 . The cable distribution system of  claim 1  wherein said address in said memory is the same as a memory address of said data portion. 
     
     
         15 . The cable distribution system of  claim 1  further comprising overwriting a portion of said header portion with an internal header. 
     
     
         16 . The cable distribution system of  claim 15  wherein internal header indicates a type of service associated with said data portion. 
     
     
         17 . The cable distribution system of  claim 1  wherein said data portion includes a plurality of data packets. 
     
     
         18 . The cable distribution system of  claim 1  wherein said remote fiber node encoding and transmitting a first portion of said data portion to a first one of said plurality of customer devices and said remote fiber node encoding and transmitting a second portion of said data portion to a second one of said plurality of customer devices. 
     
     
         19 . The cable distribution system of  claim 1  wherein said remote fiber node receiving a plurality of said downstream external protocol interface packets that include a respective said header portion and said data portion in said memory, said remote fiber node encoding and transmitting said respective data portions of said respective said downstream external protocol interface packets to one of said plurality of customer devices as a single packet.